CN1519244B - Novel lignin derivative, molded article using the derivative, and production method - Google Patents

Abstract

The invention provides a novel method for producing lignin derivatives, which is characterized in that the carbon atom at the ortho position of the phenolic hydroxyl group in the phenol derivative is combined with the carbon atom at the benzyl position in the phenylpropanyl basic unit of lignin to form diphenyl Under the basicity that can dissociate the hydroxyl group, by combining the oxygen atom in the hydroxyl group with the carbon atom at the β position, a coumarin-containing full skeleton is combined to form on the original lignin aromatic nucleus. The full body of the aryl coumarin unit.

Description

Novel lignin derivative, molded article using the derivative, and production method

This application is a divisional application of the invention patent application with application number 97182421.5. The title of the parent application with application number 97182421.5 is "Novel Lignin Derivatives, Shaped Products Using the Derivatives, and Manufacturing Method", the international filing date is September 12, 1997, and the date of entering the Chinese national phase is 2000 April 24th.

technical field

The present invention belongs to the field of utilizing lignophenol derivatives obtained by derivatizing lignin, which is a component of wood, with phenol. More specifically, the present invention belongs to the technical field of manufacturing shaped bodies from novel materials obtained by further secondary treatment of lignophenol derivatives, and the recovery of such materials from shaped bodies and the reuse of shaped body materials.

background of the invention

In recent years, people are increasingly concerned about the sustainable use of forest resources as industrial raw materials to replace fossil resources such as petroleum and coal that will be exhausted. The forest resources mentioned therein, i.e. lignocellulosic resources are composed of hydrophilic carbohydrates such as cellulose and hemicellulose and hydrophobic lignin (polyphenols), which form mutual intrusion in the cell wall. The polymer network structure (IPN) is intertwined in a complex way to form a complex. Lignocellulosic resources are various useful materials due to this complex structure.

Lignocellulosic resources, that is, the imaginary utilization form of wood materials, one is direct utilization, that is, lignocellulose resources are cut and processed into building materials or furniture materials of predetermined shapes in the form of composites , or making lignocellulosic resources into sheets or fibers, etc., and then making them into raw materials for manufacturing shaped bodies; the other is indirect utilization, that is, only extracting cellulose as a component of the composite pulp.

Considering the depletion of fossil resources in the future, these two utilization methods are very important for the reuse of lignocellulose resources.

However, in the current direct utilization method, since construction materials have a predetermined shape and are relatively large in size, processing such as crushing and pulverization is usually required for reuse. Moreover, it is difficult to separate the thermosetting resin used in the molded body from wood chips, fibers, and the like. Therefore, for direct utilization, lignocellulose resources are often not reusable and are discarded.

In addition, in the indirect utilization method, only cellulose can be reused by repeating fibrillation and sheeting processes.

In summary, the current status is that in the direct utilization mode, all lignocellulosic resources, i.e. cellulose and lignin, are not reused; while in the indirect utilization mode, no utilization or reuse as other constituents of lignin.

Lignin is the second most abundant organic substance present on earth after cellulose. The inventor focused on the function of the lignin composite structural material, and submitted a patent application on the problem of extracting a functional lignin composite material from lignocellulose resources. The first patent application is Japanese Patent Application Hei 1-55686 (Japanese Unexamined Patent Publication No. 2-233701), and the second patent application is Japanese Patent Application Hei 8-92695 (unpublished at the time of this application). The first patent application discloses a method of impregnating lignocellulose resources with phenol derivatives, contacting them with concentrated acid, grafting lignin with phenol derivatives, and separating them from cellulose. The second patent application discloses a method for producing a novel cellulose-lignin shaped body by using the graft obtained in the first patent application as a binder for the cellulosic shaped body material.

disclosure of invention

The object of the present invention is to provide a new material with further improved functions by further secondary treatment of the grafted material, and at the same time provide a cellulose-based molded body using the new material. Furthermore, the object of the present invention is to provide a method for reusing a cellulose molded body using this new material.

In order to accomplish the above objects, the present inventors proposed the following inventions.

That is to say, the first invention is a novel production method of lignin derivatives, which is characterized in that the carbon atom at the benzyl position of the phenylpropanyl basic unit in lignin is adjacent to the phenolic hydroxyl group in the phenol derivatives. The lignin phenol derivatives containing diphenylpropane unit formed by the combination of carbon atoms at the β position, under the basicity where the hydroxyl group can be dissociated, the oxygen atom in the hydroxyl group is combined with the carbon atom at the β position, so as to obtain a lignophenol derivative containing The aryl coumarin body of the aryl coumarin unit in which the coumarin skeleton is combined with the aromatic nucleus of the phenylpropane unit in lignin. The phenol derivative described in the present invention is preferably p-cresol.

The second invention is a novel lignin derivative (hereinafter referred to as aryl coumarin), which contains the coumarin skeleton represented by the following structural formula bonded to the aromatic nucleus in the phenylpropane unit of lignin The aryl coumarin full unit.

The third invention is a novel production method of lignin derivatives, which is characterized in that the aromatic carbon atoms of phenol derivatives are combined with the benzylic carbon atoms in the phenylpropane unit of lignin to form diphenyl The propane unit, under the alkalinity that the phenolic hydroxyl group of the introduced phenol derivative and/or the phenolic hydroxyl group originally existing in lignin can be dissociated, has an effect on the crosslinkability of the lignin phenol derivative containing the diphenylpropane unit. The functional group-forming compounds are heated together to introduce the cross-linkable functional group into the ortho and/or para-position of the phenolic hydroxyl group to obtain a lignin cross-linkable body having a diphenylpropane unit with a cross-linkable functional group.

The preferred condition of the present invention is that the phenol derivative is p-cresol, the compound forming the crosslinkable functional group is formaldehyde, and the crosslinkable functional group is methylol.

The fourth invention is a novel lignin derivative (hereinafter referred to as a lignin cross-linking body), which has a cross-linking functional group in the ortho and/or para position of the phenolic hydroxyl group in the lignin phenol derivative, so The above-mentioned lignophenol derivatives contain a diphenylpropane unit formed by combining its aromatic carbon atom with the benzylic carbon atom in the phenylpropane basic unit of lignin. A preferred crosslinkable functional group in such a lignin derivative is a hydroxymethyl group.

The fifth invention is a shaped body, which is shaped into fibrous, flake and powder, and is characterized in that it contains the above-mentioned aryl coumarin.

According to this shaped body, the body of the shaped material is bounded with aryl coumarin, and a shaped body having good strength and water resistance will be formed. Furthermore, the aryl coumarin can be easily extracted from the molded body and separated from the molding material by using a solvent having affinity with the arylcoumarin.

The above-mentioned molding raw material in the present invention is preferably cellulose fibers. This is because cellulosic fibers are easy to obtain and can be easily separated from aryl coumarin, so they can be used in many applications.

The sixth invention is a molded article obtained by molding a molding material into a fibrous shape, a sheet shape, a powder shape, etc., characterized by containing the above-mentioned lignin crosslinkable body.

According to this shaped body, since the shaped raw materials are bonded by the lignin crosslinkable body, it is a shaped body having good strength and water resistance. A preferable molded article of the present invention is a molded article obtained by crosslinking a lignin crosslinkable body. Because cross-linking can further improve strength and water resistance.

The seventh invention is a method for treating a molded body, which is characterized in that by adding a solvent having affinity with the arylcoumarin body to the molded body containing the above-mentioned arylcoumarin body, recovering the formed body Arylcoumarin as described above.

According to the present invention, the full body of arylcoumaran as a fiber material can be efficiently reused, and it can be separated and extracted from the molded body. Through this treatment, it is also possible to simultaneously separate out the shaped raw material for reuse.

The molding material in the present invention is preferably cellulose fibers.

If the forming material is cellulose fibers, the cellulose fibers can be easily separated after being treated with a solvent having affinity with lignophenol derivatives.

As lignocellulose-based materials, wood, waste materials, offcuts, herbs, agricultural waste, etc. can be used, and lignocellulose materials can be effectively used and reused.

A preferable type of molding material in the present invention is cellulose fibers obtained by defibrating lignocellulosic materials.

If the above-mentioned molding material is cellulose fiber obtained by defibrating a vegan cellulose material, the lignocellulose material can be molded into a novel molded body. Furthermore, cellulosic fibers are readily available, easily separated from lignophenol derivatives, and can be used in many applications. Especially when the lignophenol derivative is obtained from lignocellulosic material, the cellulose component and lignin component in the lignocellulosic material can be effectively utilized at the same time.

Brief description of the drawings

Accompanying drawing 1 is to represent the structural formula of the phenylpropane unit in lignin.

Accompanying drawing 2 is a schematic diagram showing that the side chain of the aromatic nucleus of the phenylpropane unit in lignin endows a certain structure at the α-position and β-position.

Fig. 3 is a diagram showing an example when a substituent is imparted to an aromatic nucleus of a phenylpropane unit in lignin.

Fig. 4 is a schematic diagram showing the first method for synthesizing lignophenol derivatives.

Fig. 5 is a schematic diagram showing a second method for synthesizing lignophenol derivatives.

Accompanying drawing 6 is a schematic diagram showing the reaction of lignin and phenol derivatives when contacting with concentrated acid in the phenol derivative phase interface in a two-phase separation system of phenol derivative phase and concentrated acid phase.

Accompanying drawing 7 shows the schematic diagram of the selective introduction of phenol derivatives at the α-position of the lignin side chain.

Fig. 8 is a schematic diagram showing the partial structure of lignin whose structure is changed by introducing a phenol derivative at the α-position of the lignin side chain.

In accompanying drawing 9, 9(a) represents the ultraviolet spectrum of the ground lignin, and 9(b) represents the ultraviolet spectrum of the lignin phenol derivative.

In Figure 10, 10(a) is the difference spectrum of ground lignin, and 9(b) is the difference spectrum of lignin phenol derivatives.

In Figure 11, 11(a) is the infrared spectrum of ground lignin, 11(b) is the infrared spectrum of sulfuric acid lignin, and 11(c) is the infrared spectrum of lignin phenol derivatives.

In accompanying drawing 12, 12(a) is the 1H-NMR spectrum of the acetate of the lignophenol derivative, 12(b) is the 1H-NMR spectrum of the ground lignin acetate.

Figure 13 is a table illustrating the yields of lignophenol derivatives obtained from various sources of lignocellulosic material.

Fig. 14 is a table showing the elemental analysis results of lignophenol derivatives obtained from lignocellulosic materials from various sources, the amount of cresol introduced, appearance and dissolution solvent.

Figure 15 is a table showing the distribution of hydroxyl groups in lignophenol derivatives obtained from various sources of lignocellulosic materials.

Accompanying drawing 16 shows the essential structural units that use lignophenol derivatives when making aryl coumarin full body.

Figure 17 is a schematic representation of an arylcoumarin full unit.

Fig. 18 is a schematic diagram showing an example of an arylcoumarin unit obtained from a lignophenol derivative obtained by using p-cresol as a phenol derivative.

Figure 19 is an example of an ultraviolet spectrum showing the body of an arylcoumarin.

Figure 20 is an example of an infrared spectrum showing the body of an arylcoumarin.

Figure 21 is an example of ultraviolet spectrum showing a lignin cross-linking body.

Accompanying drawing 22 is the infrared spectrum example showing a lignin cross-linking body.

Fig. 23 is a schematic diagram showing an example of structural conversion of lignin phenol derivatives, aryl coumarin and lignin cross-linking bodies obtained by using p-cresol as a phenol derivative using lignin as a raw material.

Accompanying drawing 24 is the schematic diagram of the principle of nuclear exchange method.

Accompanying drawing 25 is the schematic diagram of periodic acid oxidation treatment principle.

Accompanying drawing 26 is the schematic diagram of the structural analysis example of treating arylcoumarin by nuclear exchange method and periodic acid oxidation method.

Fig. 27 is a schematic diagram showing the process of producing a cellulose-based molded body using a secondary derivative or the like.

Fig. 28 is a schematic view showing the production process of a molded product made of cellulose-based molded products using secondary derivatives and the like.

Fig. 29 is a schematic diagram showing the migration of the secondary derivatives and the like to the surface of the molded body when the solvent in which the secondary derivatives and the like are dissolved is distilled off from the molded body.

Fig. 30 is a schematic view showing the steps of producing a molded product of a cellulose-based molded product using a secondary molded product or the like.

Fig. 31 is a schematic view showing the process of producing a molded product of a cellulose-based molded product using a secondary molded product or the like.

Fig. 32 is a schematic diagram of the process of recovering secondary derivatives and raw materials from molded bodies.

Accompanying drawing 33 is the schematic diagram of working procedure in embodiment 1～3.

Figure 34 is a data table showing properties of lignophenol derivatives and their arylcoumarin derivatives.

Figure 35 is a data table showing the distribution of hydroxyl groups and phenolic frequency in lignophenol derivatives and their arylcoumarin derivatives.

Fig. 36 is a data table showing properties of lignophenol derivatives and their lignin crosslinkable derivatives.

Fig. 37 is a data table showing hydroxyl group distribution and phenolic frequency in lignophenol derivatives and lignin crosslinkable derivatives.

Accompanying drawing 38 is the schematic view showing the supporting and loading state of the test body in the strength test.

In Fig. 39, 39(a) is a graph showing Pmax, 39(b) is a graph showing MOE, and 39(c) is a graph showing MOR.

Fig. 40 is a graph showing the volume change rate of a cellulose-based molded body obtained by using a lignophenol derivative.

Accompanying drawing 41 is the volume change rate curve of the cellulose-based molded body obtained by using aryl coumarin.

Fig. 42 is a graph showing the comparison of the volume change rate of cellulose-based molded articles obtained by using lignin phenol derivatives, aryl coumarins and lignin cross-linkable products, respectively.

Accompanying drawing 43 is the comparative data table of the water absorption rate and the volume change rate of the cellulose-based molded body obtained with lignin phenol derivative, aryl coumarin full body and lignin cross-linking body respectively.

Figure 44 is a table showing the recovery of various derivatives from shaped bodies.

Specific Embodiments of the Invention

Embodiments of the present invention will be described in detail below.

In the present invention, the arylcoumarin polymer and the crosslinkable lignin derivative are substantially obtained from lignocellulose-based materials containing lignin. The lignocellulosic material containing lignin refers to the lignified part of a plant. Specifically, various trees such as coniferous trees and broad-leaved trees, and various herbaceous plants such as rice, corn, and sugar cane can be used as the raw material of the lignocellulose material. Furthermore, the lignocellulose-based material can be used regardless of its shape such as powder or flake, but the powdery material is suitable because it can efficiently extract lignophenol derivatives. In addition, as the lignocellulose-based material, not only the waste and offcuts of the lignocellulose-based material, but also feed and agricultural waste made of the lignocellulose-based material can be used.

In order to obtain aryl coumarin and lignin cross-linking bodies from lignocellulosic materials, it is first necessary to obtain lignophenol derivatives from lignocellulosic materials. This derivative is obtained by using phenol derivatives It is formed by grafting lignin in lignocellulosic materials and introducing phenol derivatives into the specific side chain α-position (benzyl position) of the phenylpropane unit as the basic skeleton of lignin (this process is called primary Derivatization process).

In this specification, the phenylpropane unit in lignin refers to the unit whose basic skeleton is the structure of 9 carbon atoms in the structural formula shown in Fig. 1 . Among them, in this structure, the expression of -O(H) bound to the aromatic nucleus refers to the formation of a hydroxyl group sometimes due to the combination of a hydrogen atom and an oxygen atom bound to the aromatic nucleus, and sometimes refers to the combination of this oxygen atom with other The phenylpropane units form ether linkages.

For this phenylpropane unit, including on the α-position and β-position of the aromatic nucleus side chain of the basic unit, the various structures shown in Figure 2 are formed. Moreover, it also includes other substituents on the aromatic nucleus, as well as combinations with other phenylpropane units. Examples of changes in aromatic nuclei with such substituents include the four cases shown in Figures 3(a) to 3(d). Moreover, those with one or two methoxy groups at the ortho position of the aromatic nucleus phenolic hydroxyl group or ether hydroxyl group, or those with a methoxy group at one ortho position, and those with carbon atoms combined with other basic units at the other ortho position, also should be included.

In this specification and accompanying drawings, the aromatic nuclei derived from phenylpropane in lignin, including their various variation examples, are described in the article or shown in the accompanying drawings.

In the present invention, a predetermined phenol derivative is introduced into the α position of the side chain to reduce the irregularity of the lignin structure, and by performing secondary derivatization treatment on the obtained lignin phenol derivative, it can provide better function s material.

Currently, there are two methods for extracting lignin from lignocellulosic materials in the form of lignophenol derivatives. The lignophenol derivatives mentioned therein refer to polymers containing diphenylpropane units, and the polymers are introduced into phenol derivatives with C-C bonds at the α position of the side chain of the phenylpropane unit of lignin And formed. The amount and molecular weight of the phenol derivative introduced into this polymer vary depending on the type of lignocellulosic material used as a raw material and the reaction conditions.

The first method is the method described in the first patent application (JP-A-2-233701).

In this method, for example, as shown in accompanying drawing 4, lignocellulosic materials such as wood flour are soaked into liquid phenol derivatives (cresol, etc.), and after lignin is solvated with phenol derivatives, concentrated acid (such as 72% sulfuric acid) is mixed with lignocellulosic materials to dissolve the cellulose components. Using this method, a two-phase separation system of a phenol derivative that solvates the lignin and a concentrated acid that dissolves the cellulose component can be formed. The lignin solvated by phenol derivatives is only in contact with the acid at the contact interface between the phenol derivative phase and the concentrated acid phase, and the highly reactive side chain α-position (benzyl position) of the basic structural unit generated due to contact with the acid ) at the cation, which is also attacked by phenol derivatives. As a result, a phenol derivative was introduced at the α-position via a C-C bond. Furthermore, the molecular weight is lowered due to the cleavage of the benzyl aryl ether bond. As a result, the molecular weight of lignin is lowered, and a lignin phenol derivative in which a phenol derivative is introduced into the benzylic position in its basic structural unit is produced in the phenol derivative phase (see FIG. 6). From this phenol derivative phase, lignophenol derivatives can be extracted. The benzyl aryl ether bond in lignin is cleaved to lower its molecular weight, and a part of the lignin phenol derivative is obtained as a lignin lowered molecular weight aggregate. In addition, it is known that a phenol derivative is introduced at the benzyl position through its phenolic hydroxyl group.

Extraction of lignophenol derivatives from the phenol derivative phase can be performed, for example, by the following method. That is, the phenol derivative phase was added to a large excess of diethyl ether to obtain a precipitate, which was collected and dissolved in acetone. Centrifuge to remove insoluble components that are not soluble in acetone, and concentrate acetone-soluble components. This acetone-soluble fraction was added dropwise to a large excess of ether, and the precipitated part was collected. After distilling off the solvent from this precipitated part, it was dried in a drier containing phosphorus pentoxide, and a low molecular weight product containing a lignophenol derivative, that is, a crude lignophenol derivative was obtained as a dry product. In addition, crude lignin phenol derivatives can also be obtained only by removing the phenol derivatives by vacuum distillation. In addition, it is also possible to directly use the soluble fraction of acetone as the solution of the lignophenol derivative for secondary derivatization treatment.

In the second method, as shown in FIG. 5 , a lignocellulose-based material is impregnated with a solvent (for example, ethanol or acetone) in which a solid or liquid phenol derivative is dissolved, and then the solvent is distilled off (phenol derivative adsorption step). Further, concentrated acid is added to this lignocellulose-based material to dissolve the cellulose component. As a result, similar to the first method, the lignin in the state of being solvated by the phenol derivative is attacked by the cation of the highly reactive side of the lignin (side chain α position) generated by contact with concentrated acid. , can introduce phenol derivatives. Furthermore, the molecular weight of lignin is lowered by cleavage of the benzyl aryl ether bond. The properties of the obtained lignophenol derivatives were the same as those obtained by the first method. The lignophenol derivative is then extracted into a liquid phenol derivative. The extraction of lignophenol derivatives from the liquid phenol derivative phase can also be carried out in the same manner as the first method. Or pour all the reaction solution after concentrated acid treatment into excess water. The insoluble fraction was collected by centrifugation, followed by dialysis and drying. Acetone or ethanol is added to this dried product to extract lignophenol derivatives. Furthermore, similarly to the first method, the soluble matter is added dropwise to excess ether or the like to obtain a lignophenol derivative in the form of an insoluble matter.

In this method, the acetone soluble fraction can also be used as the lignophenol derivative solution for secondary derivatization treatment.

Among these two methods, the second method, especially the latter, the method of extracting and separating lignin phenol derivatives with acetone or alcohol, is economical due to the small amount of phenol derivatives used. Furthermore, this method is suitable for large-scale synthesis of lignophenol derivatives because it can process a large amount of lignocellulosic materials using a small amount of phenol derivatives.

Fig. 7 shows the state in which a phenol derivative was selectively introduced into the α-position of the lignin side chain by these methods. The fact that a phenol derivative is introduced into the phenylpropane unit of lignin and the amount of introduction can be confirmed by ¹ H-NMR and nuclear exchange analysis. Similarly, by ¹ H-NMR and nuclear exchange analysis, it was also confirmed that the phenylpropane unit was selectively introduced at the α-position of the side chain.

Figure 8 also illustrates the conversion process from native lignin to lignophenol derivatives using these methods, showing partial structural changes in native lignin and lignophenol derivatives.

Accompanying drawing 9 (a) and accompanying drawing 9 (b) represent, use the lignin phenol derivative (lignin cresol) sample that imports cresol as phenol derivative in lignocellulosic material, and degreasing Wood powder is raw material, according to the UV spectrum of the pulverized wood powder lignin (hereinafter referred to as ground lignin) sample prepared by Bjorkman method; Accompanying drawing 10 (a) and accompanying drawing 10 (b) represent respectively accompanying drawing 9 each sample Ion difference spectrum (ΔEi spectrum). In accompanying drawing 9 (a), (b) and accompanying drawing 10 (a), (b), lignophenol derivative shows very sharp peak at 280nm and 300nm place respectively, and in lignophenol derivative The peaks and peak shoulders on the long-wavelength side that were seen in the existing lignin samples were not found at all. This means that in the first derivatization process, except for the α-position of the side chain of the phenylpropane unit of lignin, there are almost no complex secondary structural changes such as the formation of a conjugated system, followed by Structural diversity is reduced by the disappearance of conjugated systems. According to the above-mentioned first method, 1 gram of wood powder is equivalent to 10 milliliters of p-cresol and 20 milliliters of 72% sulfuric acid, and stirring at 25° C. for 60 minutes can obtain the used lignocresol. When performing UV spectroscopic measurements, it is dissolved in methyl cellosolve. When ΔEi spectrum is measured, it is measured in methyl cellosolve and 1N sodium hydroxide solution.

Accompanying drawing 11 shows, the sulfuric acid lignin sample (accompanying drawing 11 (a)) that grinds lignin sample, prepares defatted wood powder by Tappi method and the lignin phenol derivative (lignin cresol) that accompanying drawing 9 uses IR spectrum (KBr method) (Fig. 11(b)). In the IR spectrum of the lignophenol derivative, each absorption peak was very sharp compared with the sulfuric acid lignin prepared with only 72% sulfuric acid, indicating that no self-condensation to cause rigidity of the molecule occurred. Furthermore, almost no absorption is shown near 1650 cm ^-1 which is assigned to the conjugated carbonyl group. In contrast, a strong absorption based on adjacent 2H on the benzene nucleus can be found around 800 cm ⁻¹ . This result is consistent with the UV spectroscopy results.

Accompanying drawing 12 shows, accompanying drawing 9 uses lignin phenol derivative (lignocresol), its acetate (accompanying drawing 12 (a)) and the acetate ester of ground lignin sample (accompanying drawing 12 (b) )) ¹ H-NMR spectrum. The acetoxy proton region (1.6-2.5ppm) overlaps with the methyl proton introduced into cresol, but from the signal pattern, the lignophenol derivative has very many phenolic hydroxyl groups, thus indicating that aliphatic hydroxyl groups are still maintained. Moreover, hydroxymethyl protons and aliphatic side chain protons (2.50-5.20 ppm) can also be clearly found, which indicates that the irregularity of natural lignin is reduced. In addition, from the integrated values of the peaks in these spectra, the number of aliphatic hydroxyl groups and aromatic hydroxyl groups can be quantitatively measured, and the amount of introduced phenol derivatives (p-cresol in this spectrum) can also be quantitatively measured.

Accompanying drawing 13 shows the yield of the lignophenol derivative obtained by introducing p-cresol as a phenol derivative into lignocellulosic materials (wood flour) of various sources (based on the ratio of the lignin contained in the wood flour) The weight % of the element is shown, and the yield is shown by the form containing the introduced cresol). Whether coniferous or broad-leaved, almost no difference in separation performance was found between tree species. According to the above-mentioned first method, these lignophenol derivatives can be obtained by using 10 ml of p-cresol and 20 ml of 72% sulfuric acid on 1 gram of wood flour from various sources and stirring at 25° C. for 60 minutes.

Accompanying drawing 14 shows in the lignocellulosic material (wood powder) of various sources, introduces the various lignocresol materials that cresol obtains (obtained under the same condition with the lignocresol of accompanying drawing 10) properties (elemental analysis results, amount of cresol introduced, appearance and dissolved solvent). Compared to ground lignin samples with minimal structural changes during isolation, lignophenol derivatives from coniferous and deciduous trees had an average of 5% higher carbon content and 5% lower oxygen content in terms of cresol incorporation. It has been found that the amount of cresol introduced is about 25% (about 0.65 mol/C9) in coniferous trees, and about 30% (about 0.9 mol/C9) in broad-leaved trees; more than 90% of its binding positions are on the α-position of lignin side chains . Moreover, the weight-average molecular weight of the lignophenol derivative derived from coniferous trees is 3000-4000, and that derived from broad-leaved trees is lower. In addition, lignophenol derivatives can be rapidly dissolved in solvents such as methanol, ethanol, and acetone.

In addition, the appearance of lignophenol derivatives showed pinkish white color despite concentrated acid treatment and introduction of a large amount of cresol. This point is very different from the black lignin after phenolization under the catalysis of sulfuric acid and hydrochloric acid in the past.

Accompanying drawing 15 shows the hydroxyl content in the lignophenol derivative (lignocresol) obtained under the same conditions as the sample in Fig. 10 using raw materials from various sources. In the lignophenol derivatives, there is no benzyl hydroxyl group at the alpha position of the side chain, while on the other hand the hydroxyl group at the gamma position of the side chain remains to the same extent as in ground lignin. The phenolic hydroxyl groups became extremely abundant due to the cleavage of benzyl aryl ether in lignin and the introduction of cresol during the treatment.

Ligninphenol derivatives used as raw materials for the synthesis of arylcoumarin polymers

The lignin phenol derivative used to synthesize the aryl coumarin polymer of the present invention must be introduced into the phenolic hydroxyl ortho-position carbon atom of the phenol derivative to be combined with the α-position carbon atom of the side chain of the phenol propane unit of lignin. That is to say, must have the structure shown in accompanying drawing 16 as basic framework. In FIG. 16, although the aromatic nuclei of the introduced phenol are described in the state without substituents other than hydroxyl groups, the phenol nuclei introduced into the lignophenol derivatives that can be used in the present invention are not limited to these. This structure may also have other substituents. In the present specification and claims, the phenol derivatives introduced with phenylpropane units include phenol derivatives having various substituents, described in the text and shown in the drawings.

The reason why the phenolic hydroxyl group of phenol is introduced is that it dissociates under alkalinity and shows the effect of the adjacent group to form the aryl coumarin structure. Therefore, in order to synthesize the lignophenol derivatives used in the synthesis of the arylcoumarin polymers of the present invention, it is necessary to use phenol derivatives in which at least one ortho-position of a phenolic hydroxyl group is free, ie, has no substituent. Because this ortho position is the binding site with the lignin matrix. Specifically, alkylphenols such as phenol and cresol, monohydric phenol derivatives such as methoxyphenol and naphthol, dihydric phenols such as catechol and resorcinol, and trihydric phenols such as pyrogallol Phenol, etc., substances that have no substituent at the ortho position of the phenolic hydroxyl group.

Whether or not such a lignophenol derivative has been obtained can be confirmed by ¹ H-NMR and nuclear exchange analysis.

Lignophenol derivatives as raw materials for synthesizing crosslinkable lignin derivatives

The lignophenol derivative used for synthesizing the crosslinkable lignin derivative of the present invention is not particularly limited. In the present invention, the free ortho-position or para-position of the phenolic hydroxyl group is used as the introduction site of the crosslinkable functional group, and this introduction site originally exists in the phenylpropane unit of lignin. This is because a crosslinkable lignin derivative can be formed by introducing a crosslinkable functional group into any part of the diphenylpropane unit in the lignophenol derivative.

Alternatively, a crosslinkable functional group can be introduced into the side of the introduced phenol derivative, and the introduced amount can be increased or adjusted to selectively form the introduced phenol derivative.

That is to say, since the crosslinkable functional group is introduced into the ortho or para position of the phenolic hydroxyl group under the basic condition of dissociation of the phenolic hydroxyl group, in the lignophenol derivatives, the phenolic hydroxyl group introduced into the phenol ortho Since at least one of the position and the para position is free, it is also possible to introduce a crosslinkable functional group on the side where the phenol derivative is introduced.

In the process of obtaining the lignin phenol derivative of the present invention, since the phenylpropane unit side chain α-position carbon atom of lignin is combined with the carbon atom at the ortho or para position of the phenolic hydroxyl group of the phenol derivative, it is necessary to obtain For cross-linked lignin derivatives, if at least two of the two ortho-positions and one para-position of a phenolic hydroxyl group are free, one of the positions becomes the binding site for the phenylpropane unit, and one remains A site for introducing a crosslinkable functional group.

Conversely, like 2,4-xylenol and 2,6-xylenol, etc., for phenol derivatives with two or more positions substituted by substituents in the ortho and para positions of the introduced phenolic hydroxyl group, the obtained lignin As for the phenol derivative, since there is no crosslinkable functional group introduction site in the introduced phenol derivative, the crosslinkable functional group can only be introduced into the lignin matrix side.

Therefore, by introducing into lignin phenol derivatives having cross-linkable functional group introduction sites with different reactivity, or by introducing one or more kinds of different phenol derivatives into lignin in combination, it is possible to control lignophenol derivatives. The number of introduction sites of the crosslinkable functional group in the derivative can further control the crosslink density of the crosslinkable lignin derivative.

In order to introduce a crosslinkable functional group to the introduced phenol derivative side, phenol and cresol (especially m-cresol) are mentioned as preferable phenol derivative. Furthermore, in order not to introduce a crosslinkable functional group into the introduced phenol derivative, 2,4-xylenol and 2,6-xylenol are mentioned as preferable phenol derivative.

Manufacture of aryl coumarin

In order to obtain aryl coumarin from lignin phenol derivatives, the above-mentioned predetermined lignin phenol derivatives, that is, the carbon atom on the ortho position of the phenolic hydroxyl group in the phenol derivative and the carbon atom on the α position of the lignin parent side chain Atom-bonded lignophenol derivatives, subjected to alkaline treatment.

This alkali treatment is a process in which the phenolic hydroxyl group introduced into the phenol derivative at the α position of the side chain is dissociated, and at the same time bonded to the carbon atom at the β position of the side chain under the action of the adjacent group effect, the The β-aryl ether bond is broken. This treatment method can form the coumarin structure shown in the following structural formula at the alpha position of the side chain. During this alkali treatment, a bond can also be formed between the phenolic hydroxyl group introduced into the phenol derivative and the β-position carbon atom, so that the phenolic hydroxyl group introduced into the phenol is etherified, and a new phenolic hydroxyl group appears in the parent benzene nucleus of lignin. It can be concluded that the alkali treatment makes the phenolic hydroxyl group (phenol activity) be introduced into the phenol derivative from the α position to transform to the lignin matrix side.

Specifically, this alkali treatment can be carried out by dissolving the lignophenol derivative in an alkali solution and allowing it to react for a certain period of time, if necessary, under heating.

The alkaline solution that can be used in this treatment, as long as it is an alkaline solution that can dissociate the phenolic hydroxyl group introduced into the phenol derivative in the lignophenol derivative, there is no particularity about the type and concentration of the alkali and the type of solvent. limit. Under alkaline conditions, if the above-mentioned phenolic hydroxyl group dissociates, the coumarin structure can be formed due to the effect of the adjacent group.

For example, a sodium hydroxide solution can be used for a lignophenol derivative into which p-cresol has been introduced. It can be confirmed that the alkali concentration in the alkali solution is in the range of 0.5-2N, and under the condition of 2 hours of treatment time, the concentration of the alkali solution has almost no effect on the degree of low molecular weight of the aryl coumarin produced from the lignophenol derivative.

The coumarin structure is easily formed by heating the ligninphenol derivative in alkaline solution. The temperature and pressure conditions at the time of heating can be set, and there are no particular limitations as long as they are within a range that does not affect the formation of the aryl coumarin body. For example, heating the alkaline solution to above 100°C can effectively obtain the full body of aryl coumarin. In addition, the aryl coumarin body can also be obtained more effectively by heating the alkaline solution to a temperature above its boiling point under pressure.

It has been found that at the same concentration in the same alkaline solution, when the heating temperature is increased from 120°C to 140°C, the higher the heating temperature, the more it can promote the formation of low molecular weight due to the cleavage of the β-aryl ether bond. change. Moreover, the higher the heating temperature within this temperature range, the more the phenolic hydroxyl groups derived from the lignin matrix aromatic nucleus increase, and the less the phenolic hydroxyl groups derived from the introduced phenol derivatives. Therefore, the degree of low molecular weight can be adjusted by using the reaction temperature, as well as the degree of transformation of the phenol nucleus from the phenol derivative to the lignin matrix from the alpha position of the phenolic hydroxyl site. That is to say, in order to promote low molecular weight, or to obtain aryl coumarin in which more phenolic hydroxyl groups are introduced from the α-position into the phenol derivative and converted to the lignin matrix, a higher reaction temperature is preferred. The heating temperature is preferably 80°C or higher and 160°C or lower. If it is significantly lower than 80°C, the reaction cannot proceed sufficiently; on the contrary, if it is significantly higher than 160°C, it is not good because some unnecessary reactions are easily derived. More preferably, it is 100° C. or higher and 140° C. or lower. Furthermore, heating under pressure is preferred.

As an example of such treatment, a preferable condition of heating at 140° C. for 60 minutes in a reaction vessel using a 0.5 N sodium hydroxide aqueous solution as an alkaline solution is mentioned. Such treatment conditions are particularly preferred for lignophenol derivatives derivatized with p-cresol.

The low-molecularization treatment of lignin graft derivatives in the alkaline solution, such as using cooling to terminate the reaction, adjusting the pH to about 2 with an appropriate acid such as 1N hydrochloric acid, regenerating the phenolic hydroxyl group into a hydroxyl group, centrifuging the precipitate obtained, Wash until neutral, freeze-dry and then dry on phosphorus pentoxide. As a result, a lignin-derived derivative having a coumarin skeleton, that is, an aryl coumarin can be obtained.

The aryl coumarin full body, as shown in accompanying drawing 17, refers to the phenol nucleus introduced on the α-position carbon atom of the aromatic nucleus side chain of the phenylpropane unit of lignin, containing the phenylpropane unit and forming aroma Lignin derivatives with bean skeleton structure (aryl coumarin unit). Its weight-average molecular weight is preferably 500-2000, and it preferably contains 0.3-0.5 mol/C9 aryl coumarin unit. Arylcoumarin, also refers to monomers consisting only of such arylcoumarin units, or which partly (at least at the end) contains polymers with arylcoumarin units, and also refers to such monomers A mixture of body and polymer forms the coumarin body. The arylcoumarin body obtained in the step of obtaining such arylcoumarin body may be in a state in which only a low-molecular-weight body is formed by cleavage of benzyl aryl ether and β-aryl ether. Usually, in the alkali reaction solution, in addition to the monomer and the polymer, the arylcoumarin body is obtained in a mixed state containing such a low molecular weight body.

Figure 18 shows an example of an arylcoumarin unit obtained from a lignophenol derivative using p-cresol cresol as the phenol derivative.

Arylcoumarin full body structure

The coumarin skeleton in the arylcoumarin body obtained in this way, the distribution of phenolic aromatic nuclei, the amount of cresols introduced, the amount of hydroxyl groups, and the overall structure can be confirmed by the nuclear exchange method and ¹ H-NMR.

Figures 19 and 20 show the UV spectrum (solvent: tetrahydrofuran) and IR spectrum (KBr method) of the arylcoumarin body.

Preparation of Lignin Crosslinking Body

The lignin cross-linkable product refers to a lignin phenol derivative in which a cross-linkable functional group has been introduced into the ortho-position and/or para-position of the phenolic hydroxyl group. Its weight average molecular weight is preferably 2,000 to 10,000, and the introduction amount of the crosslinkable functional group is preferably 0.3 to 1.5 mol/C9 unit. The crosslinkable functional group is preferably a methylol group.

A lignin crosslinkable derivative can be obtained by mixing and reacting a compound capable of forming a crosslinkable functional group in the lignophenol derivative in a state where the phenolic hydroxyl group in the lignophenol derivative can be dissociated. .

Usually, a state in which the phenolic hydroxyl group in the lignophenol derivative can be dissociated can be formed in an appropriate alkaline solution. The type, concentration, and solvent of the base to be used are not particularly limited as long as they can dissociate the phenolic hydroxyl group in the graft body, and any can be used. For example, 0.1 N aqueous sodium hydroxide solution can be used.

There are no particular limitations on the crosslinkable functional group introduced into the lignophenol derivative. It can be introduced on the aromatic nucleus of the lignin parent or on the aromatic nucleus of the phenol derivative. Specifically, by mixing polymeric compounds such as formaldehyde, glutaraldehyde, and diisocyanate with these compounds in a state capable of dissociating phenolic hydroxyl groups in ligninphenol derivatives, it is possible to introduce crosslinkable reactive groups on the above-mentioned aromatic nuclei. group. In this way, under alkalinity, since the β-aryl ether bond is also broken, the molecular weight of the lignophenol derivative can be reduced at the same time.

When mixing a crosslinkable functional group forming compound in a lignophenol derivative, from the viewpoint of efficiently introducing a crosslinkable functional group, it is preferable to add an amount of the crosslinkable functional group forming compound on a molar basis such that the lignophenol derivative The molar amount of aromatic nuclei and/or phenolic nuclei in the phenylpropane unit of medium lignin is more than double. More preferably, it is more than 10 times the molar amount, most preferably, it is more than 20 times the molar amount.

Next, in the state where the phenol derivative and the crosslinkable functional group forming compound exist in the alkaline solution, the crosslinkable functional group is introduced into the introduced benzene nucleus by heating the solution if necessary. The heating conditions are not particularly limited as long as a crosslinkable functional group can be introduced, but preferably 40 to 100°C. When it is lower than 40°C, the reaction rate of the crosslinkable functional group forming compound is extremely low; on the contrary, if it is higher than 100°C, the reaction of the crosslinkable functional group forming compound itself will cause the introduction of lignin other than the crosslinkable functional group. Activation of side reactions. More preferably 50 to 80°C, most preferably about 60°C.

The reaction can be terminated by means of cooling the reaction liquid, etc., and the acid and unreacted cross-linking functional group-forming compound can be removed by acidifying with appropriate concentration of hydrochloric acid (for example, to about pH 2), washing and dialysis, etc. Samples were recovered after dialysis by freeze drying. Dry over phosphorus pentoxide if necessary.

Structure of lignin cross-linking body

It can be confirmed by nuclear exchange method, ¹ H-NMR, etc. whether or not the target functional group and overall structure have been introduced into the o-position or para-position of phenol in the cross-linked lignin body obtained in this way. The UV spectrum (solvent: tetrahydrofuran) and IR spectrum (KBr method) of arylcoumarin are shown in Figures 21 and 22.

Figure 23 shows an example of the structural change between lignin, lignophenol derivatives, arylcoumarins and lignin crosslinkers. In this example, p-cresol was used as a phenol derivative, and a methylol group was introduced as a crosslinkable functional group.

Methods for confirming properties of lignin phenol derivatives, aryl coumarin derivatives, and crosslinkable lignin derivatives

1. Confirmation of the formation of coumarin units and quantitative determination of the distribution of phenolic aromatic nuclei

The structure of the aryl coumarin, specifically the structure of the basic unit of the aryl coumarin is confirmed by using the nuclear transformation method combined with periodic acid oxidation treatment to compare the cresol nucleus and the lignin aromatic nucleus before and after alkali treatment (mainly o-methoxyphenyl nucleus) of the phenolic frequency.

As shown in Fig. 24, the nuclear exchange method refers to a method for quantitatively obtaining phenol monomers from phenolic polymers such as lignin in a medium in which boron trifluoride (BF ₃ ) and a large excess of phenol exist. In this nuclear exchange method, the reaction between lignin and phenol can introduce medium phenol at the α position of the lignin side chain to form a diphenylmethane structure with the aromatic nucleus, and then the lignin aromatic nucleus It is freed in the form of o-methoxyphenol, etc., and the DPM conversion of the residual phenol into the medium and the free process of the phenol nucleus are repeated. Using the quantitative nature of this reaction, the binding position of the benzene nucleus on the aliphatic side chain of the lignin phenylpropane unit can be resolved.

It is also known that periodic acid oxidation treatment, as shown in Figure 25, will quantitatively destroy the aromatic nuclei of phenol. Using this method, combined with the nuclear exchange method, it is possible to analyze the distribution of hydroxyl groups introduced into the lignin aromatic nuclei and phenol nuclei at the α position. .

The method for measuring the phenolic frequency of the cresol nucleus and the o-methoxyphenyl nucleus by means of the nuclear exchange method and confirming the formation of the coumarin unit is described below.

In the following description, the lignin cresol shown in Figure 23, which is one of the lignophenol derivatives obtained by using p-cresol as a phenol derivative, will be described as an example, and the lignin cresol as a An example of the resolution of the arylcoumarin body shown in Figure 26 obtained from the starting material. Using this analytical example, the basic unit of other arylcoumarin can also be confirmed. Wherein the symbols recorded in accompanying drawing 26 are as follows.

GP: Phenolic o-methoxyphenyl core

GE: ether-type o-methoxyphenyl core

CP: phenolic cresol core introduced at the α position

CE: ether-type cresol core introduced at the α-position

As shown in Figure 26, when the nuclear exchange method is used to treat this lignin cresol, since lignin cresol has a high frequency of cresol nuclei at the α position, there During this period, the DPM structure can be formed in the initial stage. Therefore, the nuclear exchange is rapid, regardless of the phenolic nature of the o-methoxyphenyl nucleus, and the o-methoxyphenyl nucleus and the cresol nucleus are free in the form of monomers. That is, the origin of cresol dissociation is entirely CP, while the dissociation origin of o-methoxyphenyl nuclei (o-methoxyphenol and catechol) are GP and GE.

However, when the periodic acid oxidation treatment is performed, since all cresols (Cp) are phenolic, the cresol nucleus is destroyed and the phenolic o-methoxyphenyl nucleus is also destroyed. What remains is the ether-type o-methoxyphenyl nucleus (GE), and only the non-phenolic o-methoxyphenyl nucleus (GE) is freed by the nuclear exchange treatment.

On the other hand, when the aryl coumarin obtained by treating the lignin cresol with low molecular weight by alkali treatment is subjected to direct nuclear exchange treatment, the same number of o-methoxybenzene as the graft body before the alkali treatment is released. base core and cresol core. In such a low-molecular-weight treated product, when nuclear exchange treatment is performed after periodic acid oxidation treatment, only the ether-type cresol nucleus (CE) forming the aryl coumarin structure is released.

Therefore, four kinds of reactions are carried out in total before and after the alkali treatment, and the joint treatment of nuclear exchange treatment and periodic acid oxidation decomposition and nuclear exchange method is carried out. It can be confirmed whether the cresol introduced at the α position in the alkali treatment reaction has attacked the β carbon atom (whether a coumarin unit has been formed), and whether a phenolic property can appear on the o-methoxyphenyl nucleus, that is, it can Confirm the formation of the coumarin structure.

The specific method is as follows.

Preparation of samples of lignophenol derivatives and arylcoumarin samples

The samples used in nuclear exchange treatment and periodate oxidation treatment were prepared as follows.

The samples of lignophenol derivatives were prepared by the following method: After the wood powder was adsorbed to p-cresol, 72% sulfuric acid was added, and treated at room temperature for 60 minutes, the entire reaction solution was poured into excess water, and the insoluble matter was collected by centrifugation, and after dialysis dry. The dry matter was extracted with acetone, the soluble fraction was dropped into excess ether, and the insoluble fraction was dried over phosphorus pentoxide.

Arylcoumarin samples were prepared using the following method: the lignophenol derivative (lignocresol) obtained above was treated in 0.5N aqueous sodium hydroxide solution at 140°C for 60 minutes, and then acidified with 1N hydrochloric acid to pH 2, the resulting precipitate was washed to neutral, freeze-dried, and then dried over phosphorus pentoxide.

Preparation of nuclear exchange reagent

The reagents used for nuclear exchange treatment are phenol (produced by Nakalai Tesque Co., Ltd., a first-class reagent), xylene (produced by Nakalai Tesque Co., Ltd., a first-class reagent) and boron trifluoride-phenol complex (content 25%, Nakalai Tesque Co., Ltd. Produced by the company, a mixture of primary reagents) is a mixture of volume ratios of 19:10:3.

Nuclear exchange processing

Take an appropriate amount of lignophenol derivative or aryl coumarin full-body sample, place it in a 3 ml stainless steel micro-pressure kettle with two stirring steel balls in advance, and add 2 ml of nuclear exchange reagent. After sealing and fixing the autoclave, stir for more than 10 minutes to make the contents uniform. It was then heated in an oil bath at 110°C for 4 hours. The autoclave contents were stirred every 30 minutes during heating.

After the reaction was terminated, the autoclave was taken out from the oil bath, and cooled in water to terminate the reaction. After the silicone oil carried by the autoclave was completely wiped off, the autoclave was opened, and the content was washed with a small amount of ether (produced by Wako Pure Chemical Industries, Ltd., a first-class reagent) and quantitatively transferred into a 100-milliliter beaker. A known amount of internal standard substance (dibenzyl (produced by Tokyo Chemical Industry Co., Ltd.) in benzene solution) (produced by Wako Pure Chemical Industries, Ltd., primary reagent) (12 mg/ml) was added thereto, and glass fiber filter paper (Whatman GF/A 4.5 cm) to filter ether-insoluble matter, and wash several times with ether. The filtrate was transferred to a 300 ml separatory funnel, and saturated saline and sodium chloride (manufactured by Nakalai Tesque Co., Ltd., a first-class reagent) were added and stirred vigorously to inactivate BF3. The ether layer was recovered. Concentrate until every 10ml of the concentrated solution corresponds to 1ml of the reagent. The concentrate was transferred into a 50-mL Teflon-lined screw-top vial, anhydrous sodium sulfate (produced by Wako Pure Chemical Industries, Ltd., first-class reagent) was added, and placed in a dark place for dehydration overnight.

Quantitative determination of products

Take 50 microliters from the dehydrated ether solution and put it into a Teflon-lined screw-top vial with a volume of 1 milliliter, add 1 drop of pyridine (produced by Wako Pure Chemical Industries, Ltd., special reagent) and 100 microliters Bis(trimethylsilyl)trifluoroacetamide [Bis(trimethylsilyl)trifluoroacetamide, BSTFA] (Aldrich, 99+%) was placed at room temperature for 1 hour for TMS treatment. The TMS derivative of the free monomer was determined using a gas chromatography (GLC) dropping funnel. The amount of production was calculated from the working curve of the monomer. GLC conditions are as follows.

Equipment: YANAGIMOTO G-3800

Chromatographic column: cross-linked methyl silicon capillary column (Quardrex s 2006)); inner diameter 0.25 mm, length 50 m, film thickness 0.25 μm)

Sensitivity: 10-1

Attenuator: 1/1

Column temperature: Initial temperature: 130°C for 6 minutes

Rate: 3.0°C/min

Final temperature: 190°C

Injection temperature: 230°C

Carrier Gas: Helium

Detector: FID

Preparation of Periodic Acid Oxidation Treatment Reagent

To 15 g of sodium metaperiodate (produced by Nakalai Tesque Co., Ltd., special grade reagent), add 500 ml of glacial acetic acid (produced by Wako Pure Chemical Industries, Ltd., primary reagent): water (3:2, v/v)) solution. Put this periodate oxidation reagent into a brown reagent bottle and store it at 4°C.

Periodic acid oxidation treatment

Add 1 ml of glacial acetic acid to 100 mg of lignophenol derivative or aryl coumarin full body sample, dissolve the sample as much as possible, add 15 ml of periodic acid oxidation treatment reagent, stir, and treat at 4°C for 3 sky. After treatment, add it dropwise to 200 ml of cold water under stirring, and centrifuge (5°C, 3500 rpm, 10 minutes) to recover the precipitate obtained. After washing with cold water and freeze-drying, the The dried material was used as the sample after periodate treatment. The above-mentioned nuclear exchange treatment was carried out on this sample, and the product was measured according to the above-mentioned dropping funnel measurement method for the product.

2. Quantitative determination of the amount of cresol and hydroxyl group introduced

Quantitative measurement of introduced cresol and hydroxyl group was carried out by ¹ H-NMR method.

The amount of introduced cresol and hydroxyl group was analyzed by ¹ H-NMR method.

The preparation of the test samples was carried out directly on the graft body and arylcoumarin body and its acetylated substance.

Accurately weigh 20 mg of various samples and 3 mg of p-nitrobenzaldehyde (PNB) internal standard into a 1 ml vial, and use an Eppendorf pipette to completely dissolve it in deuterated pyridine: deuterated chloroform (1:3) Medium (for the acetylated sample only dissolved in deuterated chloroform), as the sample for determination.

The ¹ H-NMR measurement was performed using an R-90H Fourier transform nuclear magnetic resonance apparatus manufactured by Hitachi. From the integral curve of the obtained record chart, the amount of cresol introduced was obtained by the following calculation method.

analyze

The following shows examples of analysis applicable to lignin cresol obtained by using cresol as a phenol derivative, and aryl coumarin and crosslinkable lignin derivatives obtained by further processing this lignocresol.

(1) Quantitative determination of the amount of cresol introduced

¹ H-NMR was performed using a HITACHI R-90H Fourier transform nuclear magnetic resonance apparatus. From the integral curve of the obtained record chart, the amount of cresol introduced was obtained by the following calculation method.

I weight%={Pwt/Pm×Pn/Pi×Ci/Cn×(Cm-1)}/Lwt×100

I mole/C9＝{I wt%/(Cm-1)}/{100-Iwt/Lm}

In the formula, I wt%: import cresol amount (weight %)

P wt: weight of PNB (mg)

Pn: aromatic nucleus H number in PNB (4)

Pi: Indicates the integral value of the aromatic nucleus 4H signal region (8.40～7.80ppm) in PNB

Ci: Indicates the integral value except the methyl 3H signal region (2.40～1.60ppm) introduced into cresol

Cn: the number of protons introduced into the methyl group in cresol (3)

Cm: Molecular weight of introduced cresol (108)

Lwt: weight of lignin cresol (grafted derivative) (mg)

1 mole/C9: import cresol amount (mol/C9)

Lm: Molecular weight of 1 unit lignin (200)

(2) Quantitative determination of hydroxyl content

¹ H-NMR measurement was carried out using the same device as the above-mentioned device and according to the same sample preparation method. The phenolic hydroxyl group and the aliphatic hydroxyl group were obtained by the following calculation method from the integral curve of the obtained record chart.

In the ¹ H-NMR spectrum of the acetylated sample, the signal region (2.40-2.03ppm) representing the phenolic acetoxyproton and the signal region (2.03-1.60ppm) representing the aliphatic acetoxyproton, due to the signal region representing the introduction of cresol Since the signal regions (2.40 to 1.60) of methyl protons overlap, each integral value is corrected according to the following formula.

Aph＝Aph’-Oph×Aar/Oar

Aali＝Aali’-Oali×Aar/Oar

Among them, Aph: represents the integrated value (corrected value) of the signal region of the phenolic acetoxy proton

Aph': Integral value (correction value) representing the signal area of phenolic acetoxy proton in acetylated sample

Oph: the integral value of the overlapping area (2.40-2.03ppm) with the phenolic acetoxygen proton of the acetylated sample in the original sample

Aar: Indicates the integral value of the signal region (7.80-6.30ppm) of aromatic protons in acetylated samples

Oar: Indicates the integral value of the signal region (7.80-6.30ppm) of aromatic protons in the original sample

Aali: Indicates the integral value (correction value) of the aliphatic acetoxy proton signal area

Aali': Indicates the integral value of the aliphatic acetoxygen proton signal area (2.03-1.60ppm) in the acetylated sample

Oali: the integral value of the overlapping area (2.03-1.60ppm) of the phenolic acetoxy proton of the acetylated sample in the original sample

Based on these correction values, the amount of hydroxyl groups was calculated.

phOH wt%=(Pwt/Pm×Pn/Pi×Aph/An×OHm)/[ALwt-{Pwt/Pm×Pn/Pi×(Aph+Aali)/An×Acm-1}]×100

AliOH wt% = (Pwt/Pm×Pn/Pi×Aali/An×OHm)/[ALwt-{Pwt/Pm×Pn/Pi×(Aali+Aph)/An×Acm-1}]×100

phOH mole/C9=(phOHwt%/OHm)/{(100-Iwt%)/Lm}

aliOH mole/C9=(aliOHwt%/OHm)/{(100-Iwt%)/Lm}

in,

phOH weight %: phenolic hydroxyl group (weight %)

Pwt: weight of PNB (mg)

Pm: molecular weight of PNB (151)

Pn: aromatic nucleus H number in PNB (4)

Pi: Indicates the integral value of the aromatic nucleus 4H signal area (8.40～7.80ppm) in PNB

Aph: Indicates the integrated value (corrected value) of the phenolic acetoxy proton signal region

An: the number of protons of the methyl group in the acetoxy group (3)

OHm: mass number of hydroxyl group (17)

ALwt: weight of acetylated lignin (mg)

Aali: Indicates the integral value (correction value) of the aliphatic acetoxy proton signal area

Acm: mass number of acetoxy group (43)

phOH mole/C9: amount of phenolic hydroxyl group (mole/C9)

Iwt%: import cresol amount (weight %)

Lm: Molecular weight of a unit of lignin (200)

aliOHwt%: the amount of aliphatic hydroxyl groups (weight%)

aliOH mole/C9: aliphatic hydroxyl amount (mole/C9)

3. Quantitative determination of the amount of methylol in lignin cross-linking body

Examples in which formaldehyde is used as a crosslinkable functional group forming compound and a methylol group is introduced as a crosslinkable functional group are listed below. When another functional group is introduced, the structure can be determined similarly. Assuming that all formaldehyde is imported as hydroxymethyl groups, it is calculated according to the following formula.

HM weight %: methylol amount (weight %)

Weight of Pwt PNB (mg)

Pm: molecular weight of PMB (151)

Pn: aromatic nucleus H number in PNB (4)

Pi: Indicates the integral value of the aromatic nucleus 4H signal region (8.40～7.80) in PNB

Mi: Indicates the integral value of the methylene signal ( -CH ₂ -OAc) region (5.20～4.70) in the hydroxymethyl group

Mn: Number of methylene protons in hydroxymethyl (2)

Hmm: Mass number of hydroxymethyl group (31)

Aph: Indicates the integrated value (corrected value) of the phenolic acetoxy proton signal region

Aali: Indicates the integral value (correction value) of the aliphatic acetoxy proton signal area

An: the number of protons of the methyl group in the acetoxy group (3)

Alwt: weight of acetylated lignin (mg)

Acm: mass number of acetoxy group (43)

HM mol/C9: amount of methylol (mol/C9)

Iwt%: import cresol amount (weight %)

Lm: Molecular weight of a unit of lignin (200)

HMwt%=(Pwt/Pm×Pn/Pi×Mi/Mn×HMm)/[ALwt-{Pwt/Pm×Pn/Pi×(Aph+Aali)/An×(Acm-1)}]×100

HM Mole/C9=(Hmwt%/HMm)/[{(100-(Iwt%+Hmwt%)}/Lm

4. Average molecular weight

The molecular weights of lignin phenol derivatives, arylcoumarin and lignin cross-linking bodies were determined by gel permeation chromatography. The preparation of the measurement sample is as follows: In the test, about 2 milliliters of tetrahydrofuran (THF) (produced by Wako Pure Chemical Industries, Ltd., first-class reagent) and about 1 milligram of various Stir the derivative to dissolve it completely, add a drop of about 4% p-cresol THF solution as an internal standard, and filter it with COSMONISE Filler "S" after it is completely uniform. The measurement conditions are as follows:

Columns: Shodex KF802 and KF804

Solvent: THF

Flow rate: 1ml/min

Detector: UV (280nm)

Range: 0.32

Sample volume: 50 microliters

Working curve: It is made using polystyrene standards (Mw: 390000, 233000, 100000, 25000, 9000, 4000, 2200, 760) and bisphenol A and p-cresol. Among them, considering the difference in molecular shape between the grafted derivatives and arylcoumarin derivatives and polystyrene, the molecular weight of polystyrene was obtained by multiplying the Q factor ratio (0.5327). The weight-average molecular weight (Mw) and the number-average molecular weight (Mn) of various samples were calculated according to the following formula, and the dispersion ratio (Mw/Mn) was also calculated.

Mw＝∑(Hi×Mi)/∑Hi

Mn=∑Hi/∑(Hi×Mi)

In the formula, Hi: the height of the chromatogram read for every 0.5 ml

Mi: Molecular weight per 0.5 ml read from the working curve

Shaped body materials other than aryl coumarin and lignin cross-linked body

As the molding material for producing the molding of the present invention, other than these lignin derivatives, natural or synthetic fibrous, flake, or powder materials are used as molding raw materials. The form of the molding material is not limited to these, and materials of various forms can be used.

As the fibrous molding material, various natural or synthetic carbohydrate-based fibers, metal fibers, glass fibers, ceramic fibers, etc., or regenerated fibers thereof can be used.

Among them, it is preferable to use regenerated fibrous fibers from the viewpoint of easy availability. As the cellulosic fibers, mechanical pulp, chemical pulp, semichemical pulp and their recycled pulps can be used, and various artificial cellulosic fibers synthesized from these pulps can also be used.

As the raw material of cellulosic fiber, also can utilize the wood fiber that takes coniferous tree and broad-leaved tree as raw material to make, and any non-wood fiber such as mulberry tree, kenaf, Manila hemp, straw and bagasse.

In addition, cellulose-based fibers can also utilize pulp processed products made of lignocellulosic materials, for example, fibers obtained by defibrating various paper products such as horse manure paper and newspapers.

Various materials such as natural or synthetic carbohydrates, metals, glasses, and ceramics can be used as the sheet-shaped molding raw material. Examples of carbohydrate-based sheets include wood or natural cellulose-based sheets obtained from materials other than wood. The metal sheet includes, for example, an alumina sheet. Examples of ceramic sheets include sheets of alumina and silica. From the same viewpoint as the fibrous molding material, a cellulose-based sheet is preferable.

As the powdery molding material, for example, one obtained by pulverizing the same material as the above-mentioned sheet material, or a powdery molding material originally can be used.

Manufacture of shaped bodies from arylcoumarin and/or lignin cross-linking bodies

When producing a shaped body, either only the aryl coumarin or the lignin cross-linkable body may be used, or both the aryl coumarin body and the lignin cross-linkable body may be used simultaneously.

When using aryl coumarin full body and/or lignin cross-linking body (hereinafter referred to as secondary derivatives) to produce a molded body, the secondary derivatives, etc. are in a molten state or a state dissolved in a solvent (hereinafter referred to as liquefied state) is added to the molding raw material to solidify the secondary derivatives in this liquefied state.

Secondary derivatives, etc. can exhibit cohesiveness when changing from a liquid state to a solid state. That is, when the solvent is distilled off from the state dissolved in the solvent to precipitate a solid, or when it is cooled and solidified from the molten state itself, cohesiveness is exhibited. By utilizing such an adhesive development process, a secondary derivative or the like can be used as an adhesive for bonding molding raw materials together.

Therefore, when producing a molded body, the secondary derivative, etc., is usually added to the molding material in a solution state, and the secondary derivative is added in a liquefied state, and then added in the process of distilling off the solvent or in a solid state. , after heating and melting to form a state added in a liquid state, and then undergo a cooling process.

The secondary derivative solution mentioned here refers to a liquid in which a secondary derivative or the like is dissolved in a solvent. As the solvent used for the derivative solution, acetone, ethanol, methanol, dioxane, tetrahydrofuran, and solutions thereof dissolved in a mixed liquid with water can be used. Furthermore, a solution of a secondary derivative or the like obtained in a synthesis and separation step of producing a secondary derivative or the like from a lignocellulose-based material may also be used.

For example, a method consisting of steps shown in Figs. 27 to 31 can be mentioned as a method for producing a molded body.

As shown in Fig. 27, the cellulose fiber is molded, the molded body is impregnated with the secondary derivative, and the solvent is distilled off. By distilling off the solvent, the secondary derivatives and the like exhibit adhesiveness and exhibit adhesiveness to the molding material. As a result, by adding the secondary derivative to the cellulose fiber, a molded body in which the secondary derivative or the like acts as a binder is obtained. Such a molded body can also be pressurized and/or heat-formed if necessary.

In addition, as shown in FIG. 28 , the cellulose fiber is dipped in a solution such as a secondary derivative when molding the cellulose fiber. Thereafter, the solvent is distilled off by applying pressure and/or heating to this molded body. By distilling off the solvent, the secondary derivatives and the like exhibit adhesiveness and exhibit adhesiveness to the molding material. As a result, a lignophenol molded body can be obtained in a state where the secondary derivative or the like acts as a binder.

With the method shown in Figs. 27 and 28, secondary derivatives etc. move to the surface layer of the molded body in the step of distilling off the solvent. Accompanying drawing 29 shows the moving state of taking aryl coumarin as an example to the surface layer. That is, a large amount of secondary derivatives and the like are added and adhered to the surface layer of the molded body. Therefore, since adding a small amount of secondary derivatives, etc., can make the surface layer side can have a large amount of secondary derivatives, etc., and use the secondary derivatives, etc. Shaped body of strength and strength.

Among these, the use of highly hydrophobic aryl coumarin, that is, when aryl coumarin synthesized from a cresol-derived lignophenol derivative is used, a molded product with high hydrophobicity can be efficiently obtained.

As shown in FIG. 30 , the unmolded cellulose fiber is dipped in a solution such as a secondary derivative, and then the solvent is distilled off. Thereafter the fibers are shaped under heat and/or pressure.

According to this method, since the secondary derivatives and the like exert adhesiveness during the process of distilling off the solvent, the fibers are preliminarily added and attached. In this way, a molded body containing secondary derivatives etc. uniformly throughout can be formed from a liquid state to a solid state by heating and pressing using fibers to which secondary derivatives etc. have been previously added in a solid state. Therefore, this method is a preferred method for producing shaped bodies with uniform properties.

In addition, as shown in FIG. 31 , powdery secondary derivatives and the like are mixed with cellulose fibers and molded by heating and/or pressing. Among them, before the final forming, it is also possible to press the false forming. This pseudo-shaped body is then heat-formed and, if necessary, pressurized. This method eliminates the need for a solvent distillation step. Furthermore, it is possible to form a molded body in which the secondary derivative etc. are uniformly contained throughout the molded body, and a molded body having uniform properties can be obtained.

Among them, when manufacturing a molded body from various molding materials and secondary derivatives, depending on the type of molding material used, a pseudo-shaping process before molding can also be added, or other additional additions can also be added according to various selections of the molding method. process. For example, when fibrous pulp is used as a molding material, there are wet methods and dry methods for forming a molded body, and the pseudo-forming methods are different in the wet method and the dry method.

Manufacture of molded body from lignin cross-linking body

In the molded article using the lignin crosslinkable body, the molded article can be reinforced by generating crosslinks by heating the molding raw material to which the lignin crosslinkable body has been added. Heating may be accompanied by pressurization. Furthermore, in the process of distilling off the solvent from the molding material to which the crosslinkable derivative was added in a liquefied state, a crosslink bond can also be formed simultaneously with heating.

The cross-linked molded body of the cross-linkable derivative has improved strength as well as improved hydrophobicity.

Recovery of arylcoumarin from shaped bodies

As shown in Fig. 32, by further adding a solvent to the molded body of the present invention, the fibers and aryl coumarins are completely separated and can be recovered separately.

Using a solvent having affinity with aryl coumarin (hereinafter referred to as the present solvent), aryl coumarin can be extracted from the molded body into this solvent.

In this case, examples of the solvent include acetone, ethanol, methanol, dioxane, and tetrahydrofuran, their mixed solutions with water, aqueous alkali solutions, and the like. For simplicity, acetone and alcohols are preferred. Furthermore, an aqueous alkali solution is preferable in view of cost.

The specific method of recovering the full body of aryl coumarin is to immerse it in a solvent compatible with the full body of aryl coumarin while maintaining the original shape of the shaped body or in the state of being processed into small pieces, or to add stirring in addition to immersion . As a result, the arylcoumarin was able to dissolve in solution. By making shaped bodies into small pieces and stirring them in a solvent, they can be rapidly separated and extracted. In addition, in the case of maintaining the original shape of the molded body, it is immersed in an arylcoumarin full body affinity solvent, non-aqueous solvent (such as acetone), and extracted by standing without stirring. In particular, when the molding material is cellulose, the molded body is defibrillated into a molding material while extracting the full body of arylcoumarin, and then immersed in an aqueous alkali solution and stirred.

In this way, the recovered arylcoumarin body can be reused in various fields such as the production of shaped bodies. Furthermore, the molded raw material separated at the same time can also be reused in various processed products such as manufacturing molded objects.

Recovery of lignin cross-linked bodies from molded bodies

When using a lignin cross-linkable body, when heating without cross-linking to produce a molded body, it can also be recovered from the molded body with a lignin cross-linkable body-compatible solvent like the aryl coumarin body Lignin cross-linking body. Examples of the lignin cross-linking substance affinity solvent include acetone, ethanol, methanol, dioxane, their respective mixed solutions with water, aqueous alkali solution, tetrahydrofuran, and the like. For simplicity, acetone and alcohols are preferred. Furthermore, an aqueous alkali solution is preferable in consideration of cost.

According to the present invention, for various lignocellulosic materials, the lignin phenol derivatives are obtained through the phase separation process of concentrated acid and phenol derivatives, and the aryl group is obtained by performing secondary derivatization treatment on this derivatives. Cougar bean full body or lignin cross-linked body, this method can be used to manufacture shaped bodies that combine them with various fibers. Derivatives and fibrous material in the shaped body can be separated from the shaped body. Therefore, by using the full body of aryl coumarin and the crosslinkable body as the material of the molded body, it is possible to repeatedly manufacture and disassemble the molded body. Thus, lignocellulose-based materials can be efficiently reused.

The aryl coumarin obtained in the invention can be used for ultraviolet absorbers and lignin materials with low protein adsorption.

The cross-linked lignin body obtained in the present invention can be used for switching elements, highly hydrophilic protein adsorbents, and ultraviolet absorbers.

Example

The following examples will be given to describe the present invention in detail. In the following examples, the production of cellulosic fiber shaped articles using aryl coumarin and lignin cross-linkable articles and their recovery from the shaped articles will be described.

FIG. 33 shows the steps involved in Examples 1-3.

Embodiment 1: Synthesis of lignophenol derivatives

Using black pine (Pinus Thunbergii) as lignocellulosic material, lignocresol was synthesized as a lignophenol derivative according to the following procedures. That is to say, after adding the acetone solution containing p-cresol (the molar weight of p-cresol is about three times of lignin _C9 in this black pine defatted wood powder per unit molar amount) in black pine defatted wood powder, fully Stir and leave overnight to impregnate the wood powder with p-cresol. Then spread the wood powder thinly on the material bed, place it in a ventilated place until there is no smell of acetone, and distill off the acetone. Wherein the unit amount of lignin C9 in the black pine degreased wood powder can be calculated according to the elemental analysis of the lignin in the black pine defatted wood powder.

Then, take out 250 grams of wood powder that has adsorbed p-cresol and put it into a beaker, add 1200 milliliters of 72% sulfuric acid while stirring with a glass rod. After stirring for about 10 minutes, stir with a stirrer for 1 hour, then transfer to 10 liters of water to terminate the reaction. After standing for several days, the precipitate was partially deacidified by dialysis. After drying the precipitate for several days in a drier with an internal temperature of 40°C, the lignophenol derivatives were partly extracted into acetone, and the acetone part was added dropwise to a large excess of benzene-hexane (2:1, v/v), the resulting precipitate was washed with ether. After the precipitate is often dried under mild and normal pressure, it is dried on phosphorus pentoxide under reduced pressure to obtain a lignophenol derivative (lignocresol).

The molecular weight, cresol incorporation amount, hydroxyl distribution and phenolic frequency of this lignophenol derivative are shown in Figs. 34 and 35 of the accompanying drawings.

Embodiment 2: the synthesis of aryl coumarin

4 grams of lignophenol derivatives obtained in Example 1 were taken out and placed in a stainless steel autoclave, dissolved in 80 ml of 0.5N aqueous sodium hydroxide solution, and heated at 140° C. to react. Cool to stop the reaction, acidify to pH 2 with 1N hydrochloric acid, collect the resulting precipitate by centrifugation, and wash until neutral. The obtained precipitate was freeze-dried, and then dried over phosphorus pentoxide under reduced pressure to obtain the full body of aryl coumarin. The molecular weight, cresol incorporation amount, hydroxyl distribution and phenolic frequency of the obtained arylcoumarin are shown in FIGS. 34 and 35 .

Embodiment 3: the synthesis of lignin cross-linking body

Lignocresol was obtained in the same manner as in Example 1. The molecular weight of this lignin cresol and the amount of cresol introduced are shown in FIG. 36 .

Get 20 grams of this lignocresol derivative and place it in a three-necked flask, dissolve it in 1.2 liters of 0.1N sodium hydroxide, add 180 milliliters of 37% formaldehyde solution (equivalent to introducing cresol and lignin parent aromatic nucleus 20 mole times formaldehyde), heated at 60°C for 3 hours, after introducing cross-linkable functional groups, cooled to stop the reaction, acidified to pH 2 with 5% hydrochloric acid, and moved the entire solution into a dialysis membrane to remove acid and unreacted formaldehyde. After dialysis, the recovered sample was freeze-dried, and then dried under reduced pressure on phosphorus pentoxide to obtain a lignin cross-linking body. The molecular weight and the amount of introduced cresol of this lignin cross-linking body are shown in FIG. 36 . Also, its distribution of hydroxyl groups and the amount of methylol groups are shown in Fig. 37 of the accompanying drawings.

Example 4: Addition and adhesion of various derivatives to cellulosic fibers

Use recycled paper as the cellulose material, soak the recycled paper in water overnight, fully defibrate, collect the fibers with a cylinder with a diameter of about 10 cm, and then dehydrate and dry to make a diameter of about 100 mm and a thickness of about 9 mm disc-shaped spacers.

From this fiber mat, the pad A (20 mm x 90 mm) for strength test preparation and the pad B (20 mm x 20 mm) for water absorption test sample preparation were cut out from this fiber mat with an electric circular saw.

(1) Preparation of gaskets for strength test

The lignophenol derivative obtained in Example 1 and the aryl coumarin body obtained in Example 2 were added to the gasket A so that the adsorption amount accounted for 5, 10 or 20% by weight, respectively. Furthermore, a lignin cross-linkable body was further added to the mat A so that the adsorption amount was 15% by weight. That is, the above-mentioned lignophenol derivatives, aryl coumarins, and lignin crosslinkables were dissolved in acetone to prepare additive adsorption solutions. In a cylindrical stainless steel container with a diameter of 10 cm, add a predetermined amount of each of the above-mentioned added adsorption solutions, so that the amount of adsorbed lignin phenol derivatives and aryl coumarin in various gaskets A reaches 5%, 10% % or 20%, and the added adsorption amount of the lignin cross-linked body obtained in Example 3 reaches 15%, soaked in this solution overnight, so that the pad A is fully soaked with the added adsorption solution. Then, the upper and lower sides of the spacer A were exchanged every 1 hour, and the acetone was slowly evaporated under this condition, so that various derivatives were adsorbed on the spacer A.

When it was visually observed that there was no acetone in the container, the spacer A was taken out from the container, and the acetone remaining in the spacer A was evaporated in a normal-temperature blower drier. After drying in a desiccator at a temperature of 60° C., the weight was measured. The amount of each derivative added was calculated by subtracting the original weight of the gasket from the weight after adding the derivative.

Gasket A having adsorbed a cross-linkable body was heat-treated at 170° C. for 60 minutes after adsorbing the cross-linkable body to obtain a heat-treated body.

(2) Preparation of gasket for water absorption

As in the case of the gasket for the strength test, the lignophenol derivative obtained in Example 1 and the arylcoumarin obtained in Example 2 were added to the gasket B so that the adsorption amount was 5% by weight, respectively. , 10% or 20%. Furthermore, as in the case of the gasket for the strength test, a lignin crosslinkable body was added to the gasket B so that the adsorption amount became 20% by weight.

In addition, various heat-treated products were prepared by heating the gasket B to which various derivatives were added at 170° C. for 60 minutes (only heat-treated products were prepared for the lignin cross-linkable body adsorption gasket).

In order to perform a comparison in the evaluation described later, a control gasket to which nothing was added was prepared by the same process as in this example except for the addition of the adsorption process. A heat-treated body was also prepared by heating at 170° C. for 60 minutes for the gasket for the control.

Example 5: Evaluation

The various gaskets thus prepared were tested for the following items.

Appearance of gasket

Various gaskets were visually observed. All kinds of gaskets are colored brown in advance, and the color tone of each heat-treated body made of this gasket is colored dark.

Gasket strength test

Using the steel device shown in Figure 38, load the test body under the span of 80 mm supported by the gasket A and the control gasket for the strength test. Concentrate loading on the surface of the test body in the center of the entire span at an average speed of 2 mm/min.

According to this test device and method, the load-deflection curve was measured, and the flexural Young's modulus (MOE) and flexural modulus (MOR) were calculated from the curve. Pmax was calculated.

The results are shown in Figure 39(a), (b) and (c).

From the results of Figure 39 (a), (b) and (c), it can be seen that compared with lignophenol derivatives, the Pmax, bending Young's modulus, and bending fracture coefficient of aryl coumarin are all excellent . Therefore, it is shown that the molded body added with aryl coumarin has good strength compared with the corresponding molded body using lignophenol derivatives. Furthermore, it can be seen that the function of the aryl coumarin as a binder is improved even if the molecular weight of the lignophenol derivative is lowered.

In addition, it was also found that the molded body (heat-treated body) using a cross-linkable body has Pmax, flexural Young's modulus, and flexural fracture coefficient that can significantly improve the full-body performance of aryl coumarin, and the strength is greatly improved by cross-linking. Great improvement.

Water absorption test

A stainless steel mesh was set at the bottom of the spacer, filled with water so that the distance between the bottom of the mesh and the water surface was 3 cm, and the water temperature was kept fixed at 25°C. Immerse the pad B prepared for the water absorption test in it, during which the sample should not float up and keep the upper surface at 3 cm below the water surface, place it on the pad B with a stainless steel mesh as a weight, and place it like this for 1 Hour.

After the preset time, take out the impregnated gasket B and remove it from the stainless steel net. After 10 minutes, quickly transfer the test body to the filter paper by hand to remove the surface moisture, measure the weight and size, and calculate the volume relative to that before immersion. rate of change. The results are shown in Figures 40-42.

Put the gasket B after the water immersion test into a desiccator, place it at 105°C for 15 hours, take it out and cool it, then measure its weight and size. The volume change rate of the gasket B after drying was calculated, and compared with the volume change rate after the water immersion test, the dimensional stability of the molded product was evaluated. The results are shown in Figures 40-43.

The results in Figure 40 show that after adding and adsorbing ligninphenol derivatives to the gasket B, the volume change rate of the non-heat-treated body and the heat-treated body under different additions is about 5-10%. After the volume change rate is about -3 ~ 2%.

In contrast, for gasket B (unheat-treated body and heat-treated body) on which aryl coumarin was adsorbed, the volume change rate after water immersion was about 7-10%, and the volume change rate after drying was about 7-10%. About -1 to 1%. That is to say, the volume change rate after water immersion is not much different from that of the molded body adsorbed with lignophenol derivatives, but the volume after re-drying is almost the same as before water immersion (see Figure 41). Therefore, the dimensional stability is good by adding the gasket B which has adsorbed the whole body of aryl coumarin. Moreover, the water absorption rate is almost the same as that of the lignophenol derivative.

Gasket B to which a cross-linkable substance was added had a volume change rate of about 7% after water immersion, but after drying, the volume almost returned to the level before water immersion, so the dimensional stability was good. In terms of water absorption, the water absorption of the gasket B with aryl coumarin and the gasket B with lignophenol derivatives is almost 60%. It can be seen that the water resistance is improved after crosslinking (see accompanying drawing 42 , this figure compares heat-treated bodies with 20% addition of various derivatives).

These results indicate that the water absorption of the gasket can be reduced by adding aryl coumarin and lignin cross-linkable lignin in which lignin cresol is secondary derivatized to the molding raw material. This result indicates that dimensional stability to water has been imparted. This tendency was particularly evident in the gasket B (heat-treated product) to which the lignin cross-linkable product was added.

Embodiment 6: the test that reclaims lignin cresol from horse manure paper

According to Example 4, the gasket B for the water absorption test, in which the lignin phenol derivative, aryl coumarin, and lignin crosslinking substance were adsorbed, was prepared and used as a gasket for the recovery test. Moreover, with regard to adding adsorbents to lignophenol derivatives and adding adsorbents to aryl coumarin, a non-heat-treated body and a heat-treated body (170° C. for 60 minutes) were prepared, which were used as gaskets for recovery tests; for lignin cross-linking In general, a heat-treated body (170° C. for 60 minutes) was used as a gasket for the recovery test. The amount of each derivative added was 20% by weight based on the weight of the cellulose fiber.

These pads were soaked in approximately 30 mL THF in a vial. After standing for 2 days without stirring, the soaking liquid was filtered, and after washing with THF, the filtrate and washing liquid were combined. After THF was distilled off, the obtained fraction was used as a recovery fraction. The results are shown in Figure 44.

The results in Figure 44 illustrate that the arylcoumarin body was 100% recovered.

The fact that the recovery is good also means that no arylcoumarin remains intact even in cellulosic materials. Among them, for the lignin cross-linking body, only a trace amount of the lignin cross-linking body can be recovered due to its cross-linking structure.

Among them, in the case where the lignophenol derivative and the aryl coumarin were full, the cellulosic material was recovered in a reusable state.

Therefore, according to the first to fourth inventions, the structural components of the lignocellulose complex in forest resources can be effectively utilized, and a new functional material can be provided.

According to the fifth invention, it is possible to provide a molded body that is easily integrated with the molding material and separated again, and can be reused with the molding material and the adhesive.

According to the sixth invention, a molded body having water resistance and strength can be provided.

According to the seventh invention, not only the whole body of aryl coumarin can be efficiently recycled, but also the molding raw material can be efficiently reused.

Claims (22)

1. A lignin cross-linking body, which has a diphenylpropane unit, is a diphenylpropane unit grafted with a phenol derivative on the benzyl position of the phenylpropane unit of lignin, combined with the phenol The diphenylpropane unit to which the phenol derivative is grafted is the ortho- or para-position carbon atom of the phenolic hydroxyl group possessed by the derivative, In the diphenylpropane unit, a methylol group as a crosslinkable functional group is bonded to either or both of the ortho-position and the para-position of the phenolic hydroxyl group in the diphenylpropane unit. 2. The lignin crosslinkable product according to claim 1, wherein the weight average molecular weight is 2,000 to 10,000. 3. The lignin crosslinkable product according to claim 1, wherein the molar ratio of the crosslinkable functional group to the phenylpropane unit is 0.3 to 1.5. 4. The cross-linkable lignin product according to claim 1, wherein the carbon atom at the ortho position to the phenolic hydroxyl group of the phenol derivative is bonded to the carbon at the benzylic position of the phenylpropane unit. 5. The lignin cross-linkable product according to claim 1, wherein at least one cross-linkable functional group is bonded to the ortho-position and para-position of the phenolic hydroxyl group of the aromatic ring of the phenylpropane unit of the above-mentioned lignin. Either or both parties. 6. The lignin cross-linkable body according to claim 1, wherein at least one cross-linkable functional group is bonded to either or both of the ortho-position and the para-position of the phenolic hydroxyl group of the above-mentioned phenol derivative, or is bonded to Either one or both of the ortho-position and the para-position of the phenolic hydroxyl group of the aromatic ring of the phenylpropane unit of the above-mentioned lignin. 7. The cross-linkable lignin product according to claim 1, wherein the phenol derivative is m-cresol or p-cresol. 8. The cross-linkable lignin product according to claim 1, wherein the phenol derivative is 2,4-xylenol or 2,6-xylenol. 9. The cross-linkable lignin product according to claim 1, further comprising a phenylpropane unit. 10. The preparation method of the lignin cross-linking body as claimed in claim 1, has the following steps: A process for obtaining lignophenol derivatives, by adding a concentrated acid to lignin solvated with a phenol derivative, and bonding the phenolic hydroxyl group possessed by the above-mentioned phenol derivative to the benzyl position of the phenylpropane unit of the lignin The carbon atom on the ortho or para position becomes a diphenylpropane unit, thereby obtaining a lignophenol derivative, In the step of producing a lignin cross-linkable body, the lignophenol derivative is reacted with formaldehyde under alkaline conditions capable of dissociating the phenolic hydroxyl group of the introduced phenol derivative, and the phenol derivative introduced above is Either one or both of the ortho-position and the para-position of the phenolic hydroxyl group is introduced into a crosslinkable functional group to produce a lignin crosslinkable body. 11. The method according to claim 10, wherein the step of producing a cross-linkable lignin derivative is performed at a temperature between 40°C and 80°C. 12. The method according to claim 10, wherein the phenol derivative is m-cresol or p-cresol. 13. The method according to any one of claims 10-12, wherein the phenol derivative is 2,4-xylenol or 2,6-xylenol. A molded article comprising the lignin cross-linkable product according to claim 1 as a binder. 15. The molded article according to claim 14, wherein the base material of the molded article is in any shape of sheet, fiber or powder. 16. The molded article according to claim 15, wherein the base material of the molded article is a cellulose-based material. 17. A method for producing a molded body, comprising the steps of: The step of supplying the lignin cross-linkable body according to claim 1 to a molding material, A step of molding the molding material from the lignin crosslinkable body. 18. The method according to claim 17, wherein in the molding step, the molding material to which the lignin crosslinkable body is supplied is further heated. 19. The method according to claim 18, wherein the crosslinkable functional group in the lignin crosslinkable body is crosslinked by the heating. 20. A method for treating a molded body, comprising a step of adding a solvent having affinity for the lignin crosslinkable body to the molded body, the molded body being obtained by the crosslinkable lignin according to claim 1. The body is heated without crosslinking the resulting shaped body. 21. The method according to claim 20, wherein the solvent is selected from acetone, ethanol, methanol, dioxane, a mixture of any of the above and water, an aqueous alkali solution, and tetrahydrofuran. 22. The method according to claim 20, further comprising a step of recovering either or both of the lignin crosslinkable body and the base material of the molded body.

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