JP7086678B2 - Complex and its manufacturing method - Google Patents

Description

The present invention relates to a complex and a method for producing the complex.

Cellulose is a main component of plant cell walls and plant fibers, and is a natural polymer in which a large number of β-glucose molecules are linearly polymerized by glycosidic bonds, so that the environmental load is small. In this cellulose fiber, single cellulose nanofibers having a width of 3 to 4 nm, which is a basic unit, are bundled to form cellulose nanofibers having a width of 10 to 20 nm, which is a basic unit in a cell wall, and the thickness is further increased. It has a structure of several tens of μm bundles.

In recent years, these cellulose nanofibers have been found to have excellent properties such as high elastic modulus, high strength, low linear expansion coefficient, and gas barrier properties, and are lighter than glass fibers, carbon fibers, and inorganic fillers. Therefore, research and development are being carried out assuming various uses such as resin reinforcing materials, paint additives, films, and thickeners.

As a method for producing cellulose nanofibers, a method of mechanically defibrating using a high-pressure disperser or a grinder, or a method of chemically hydrophilizing pulp with a cationizing agent and then mechanically deflating using a kneader, etc. Examples thereof include a method of defibrating, a method of partially oxidizing using a TEMPO catalyst and the like to facilitate chemical defibration.

By the way, cellulose nanofibers are rarely used alone, and are generally used in combination with organic components and organic solvents. Since cellulose constituting the cellulose nanofibers has a large number of hydroxyl groups of glucose molecules, there is a problem that hydrogen bonds between the hydroxyl groups are likely to occur, and as a result, aggregation of the cellulose nanofibers is likely to occur. Further, as described above, since cellulose has a large number of hydroxyl groups on its surface, it has a problem that it has extremely high hydrophilicity and lacks affinity with an organic solvent which is hydrophobic.

That is, although cellulose nanofibers exist stably in water, it is difficult to combine them with hydrophobic polymers or hydrolyzable polymers (particularly melt-kneading) in a state containing a large amount of water. On the other hand, when dried, it aggregates and becomes a relic in the polymer, which deteriorates the characteristics, so that there is a problem that it is difficult to exhibit the characteristics possessed by the nanofibers in the polymer.

In order to solve this problem, a method of hydrophobizing cellulose nanofibers has been studied, but most of the methods have a method of substituting a hydroxyl group of cellulose nanofibers with a hydrophobic substituent by a chemical method. In addition to being costly, such a method has a problem that aggregation due to hydrogen bonds cannot be suppressed because only a part of the hydroxyl group is replaced.

Although ordinary cellulose fibers have the same problems, it can be said that they are particularly prominent in cellulose nanofibers in which many hydroxyl groups are exposed on the surface with respect to the weight.

In view of the above circumstances, an object of the present invention is to improve the strength of the resin composition by hydrophobizing the cellulose by a method other than substituting the hydroxyl group of the cellulose with a hydrophobic substituent. Is to provide a possible complex.

As a result of diligent research to achieve the above object, the present inventors have provided a conventional epoxy-based resin layer having a predetermined chemical structure on the surface of cellulose without chemically modifying the cellulose. It has been found that a composite having a performance equal to or higher than that of a composite for reinforcing a resin can be obtained. The present inventors have further studied based on such findings, and have completed the present invention.

（式中、環Ｚはアレーン環、Ｘは下記式（２）で表わされる基を表わし、Ｒ^１及びＲ^２は、それぞれ、任意の置換基を表わし、ｎは１～３の整数、ｐは０以上の任意の整数、ｋは０～４の整数を表わす。）

（式中、Ｒ^３はアルキレン基、ｍは０以上の任意の整数を表わす。）
項７．
前記セルロースは、直径が３～１０００ｎｍのセルロースナノファイバーである、項１～６の何れかに記載の複合体。
項８．
前記セルロース１００質量部に対して、前記芳香族エポキシ化合物を２～１００質量部含む、項１～７の何れかに記載の複合体。
項９．
有機溶媒中に、項１～８の何れかに記載の複合体を含む、組成物。
項１０．
前記有機溶媒の沸点が１１０℃以上である、項９に記載の組成物。
項１１．
前記有機溶媒は水酸基を有していない、項９又は１０に記載の組成物。
項１２．
さらに水を含み、組成物中における前記水の含有量は、組成物１００質量％中１０質量％以下である、項９～１１の何れかに記載の組成物。
項１３．
項１～８の何れかに記載の複合体及び樹脂を含有する、樹脂組成物。
項１４．
前記樹脂は、ポリエステル系樹脂、ポリアミド系樹脂、及びポリカーボネート系樹脂からなる群より選択される１種以上である、項１３に記載の樹脂組成物。
項１５．
前記樹脂は、バイオマスプラスチック及び微生物産生プラスチックからなる群より選択される１種以上である、項１３に記載の樹脂組成物。
項１６．
前記樹脂は、ポリ乳酸、ポリアミド４、ポリアミド１１、ポリブチレンサクシネート、ポリヒドロキシブチレート、及びこれらの構造を含有する共重合体からなる群より選択される１種以上である、項１３に記載の樹脂組成物。
項１７．
セルロース、及び該セルロース表面の一部又は全体を被覆する芳香族エポキシ系樹脂層を有する複合体の製造方法であって、
前記セルロースに、芳香族エポキシ化合物及び有機溶媒を含有する芳香族エポキシ系樹脂層形成用溶液を加える工程１を有することを特徴とする、製造方法。
項１８．
前記芳香族エポキシ系樹脂層形成用溶液は、さらに、水を含有し、
前記工程１の後に、加熱及び／又は減圧により、前記芳香族エポキシ系樹脂層形成用溶液中の水を除去する工程２を有する、項１７に記載の製造方法。 That is, the present invention provides the following complex.
Item 1.
A complex having cellulose and an aromatic epoxy resin layer that covers a part or all of the surface of the cellulose.
Item 2.
Item 2. The complex according to Item 1, wherein the aromatic epoxy compound contained in the aromatic epoxy resin layer has two or more aromatic rings.
Item 3.
Item 2. The complex according to Item 1 or 2, wherein the aromatic epoxy compound has two or more epoxy groups.
Item 4.
Item 2. The complex according to any one of Items 1 to 3, wherein the aromatic epoxy compound has a polycyclic aromatic structure.
Item 5.
Item 4. The complex according to Item 4, wherein the polycyclic aromatic structure is a fluorene structure.
Item 6.
Item 5. The complex according to Item 5, wherein the fluorene structure is represented by the following formula (1).

(In the formula, ring Z represents an arene ring, X represents a group represented by the following formula (2), R ¹ and R ² each represent an arbitrary substituent, n is an integer of 1 to 3, and p is an integer of 1 to 3. Any integer greater than or equal to 0, k represents an integer from 0 to 4)

(In the formula, R ³ represents an alkylene group and m represents an arbitrary integer of 0 or more.)
Item 7.
Item 6. The complex according to any one of Items 1 to 6, wherein the cellulose is a cellulose nanofiber having a diameter of 3 to 1000 nm.
Item 8.
Item 2. The complex according to any one of Items 1 to 7, which contains 2 to 100 parts by mass of the aromatic epoxy compound with respect to 100 parts by mass of the cellulose.
Item 9.
A composition comprising the complex according to any one of Items 1 to 8 in an organic solvent.
Item 10.
Item 9. The composition according to Item 9, wherein the organic solvent has a boiling point of 110 ° C. or higher.
Item 11.
Item 9. The composition according to Item 9 or 10, wherein the organic solvent does not have a hydroxyl group.
Item 12.
Item 2. The composition according to any one of Items 9 to 11, further comprising water, wherein the content of the water in the composition is 10% by mass or less in 100% by mass of the composition.
Item 13.
A resin composition containing the complex and resin according to any one of Items 1 to 8.
Item 14.
Item 3. The resin composition according to Item 13, wherein the resin is at least one selected from the group consisting of polyester-based resins, polyamide-based resins, and polycarbonate-based resins.
Item 15.
Item 3. The resin composition according to Item 13, wherein the resin is at least one selected from the group consisting of biomass plastics and microbially produced plastics.
Item 16.
Item 13. The resin is one or more selected from the group consisting of polylactic acid, polyamide 4, polyamide 11, polybutylene succinate, polyhydroxybutyrate, and a copolymer containing these structures. Resin composition.
Item 17.
A method for producing a complex having cellulose and an aromatic epoxy resin layer that covers a part or the whole of the surface of the cellulose.
A production method comprising the step 1 of adding a solution for forming an aromatic epoxy resin layer containing an aromatic epoxy compound and an organic solvent to the cellulose.
Item 18.
The solution for forming an aromatic epoxy resin layer further contains water and
Item 17. The production method according to Item 17, further comprising step 2 of removing water in the aromatic epoxy resin layer forming solution by heating and / or depressurizing after the step 1.

According to the complex according to the present invention, it is possible to provide a complex capable of improving the strength of the resin composition without chemically modifying the surface of cellulose.

(1. Complex)
The complex of the present invention is characterized by having a cellulose and an aromatic epoxy resin layer that covers a part or the whole of the surface of the cellulose.

(1.2. Cellulose)
As the cellulose, known ones can be widely adopted, and there is no particular limitation. Further, any of plant-derived cellulose, animal-derived cellulose, and bacterial-derived cellulose can be preferably used. These may be used individually by 1 type, or may be used in combination of 2 or more type.

Plant-derived cellulose includes, for example, hardwood-derived cellulose (eucalyptus, poplar, etc.), conifer-derived cellulose (pine, fir, cedar, hinoki, etc.), herbaceous-derived cellulose (wara, bagasse, yoshi, kenaf, abaca, sisal, etc.). , And seed hair fiber (cotton, etc.) can be selected. The raw material pulp may be mechanical pulp obtained by mechanically processing wood chips, chemical pulp obtained by chemically removing non-cellulose components from wood chips, and dissolving pulp obtained by removing non-cellulose components. It may be pulp.

In addition, cellulose derived from animals such as sea squirts, cellulose derived from bacteria such as nata de coco, and the like can be used. Further, the cellulose does not necessarily have to be composed of only a pure cellulose component, and a non-cellulose component may be attached to the cellulose as the main component. Of course, it may be composed only of a pure cellulose component.

The main non-cellulose component attached to the cellulose nanofiber is not particularly limited, and can be appropriately selected depending on the use of the complex. For example, hemicellulose and lignin can be mentioned. The larger the amount of hemicellulose, the easier it is to deflate during the production of cellulose nanofibers, but the elastic modulus of the obtained resin composition tends to decrease. The greater the amount of lignin, the more difficult it is to deflate during the production of cellulose nanofibers, but since it has a phenolic hydroxyl group, it tends to react with the aromatic epoxy described later to cause a desirable cross-linking reaction during the production of the composite.

Further, the ratio of the pure cellulose component in the cellulose may be appropriately set according to the use of the complex. For example, when the complex is used for the purpose of resin reinforcement, the pure cellulose component ratio is 70% by mass or more in 100% by mass of cellulose in order to effectively utilize the strength characteristics of the cellulose component. Is preferable, and 80% by mass or more is more preferable. The upper limit of the ratio of pure cellulose components can be 100% by mass. In the present specification, the cellulose ratio is defined as the ratio of a pure cellulose component in which β-glucose molecules are linearly polymerized by glycosidic bonds with respect to 100% by mass of the total mass of cellulose.

The degree of polymerization of the pure cellulose component contained in the cellulose may be appropriately set according to the use of the complex. The lower the degree of polymerization of the cellulose component contained in the cellulose, the easier it is for the cellulose to be defibrated. On the other hand, the higher the degree of polymerization of the cellulose component contained in cellulose, the higher the elastic modulus of the complex and the composition can be obtained. In order to obtain a high-strength resin composition, it is preferable to use a cellulose component having a degree of polymerization of 500 or more, and it is more preferable to use a cellulose component having a degree of polymerization of 600 or more. The upper limit of the degree of polymerization of the cellulose component is not particularly limited, but is preferably 100,000, for example.

Regarding the degree of crystallinity of the pure cellulose component contained in cellulose, the lower the crystallinity, the easier it is for the cellulose to be defibrated, but the higher the crystallinity, the higher the elastic modulus and the composition can be obtained. In order to obtain a high-strength composition, the crystallinity of the pure cellulose component contained in cellulose is preferably 60% or more, and more preferably 70% or more. The upper limit of the crystallinity of the cellulose component is not particularly limited, but is preferably 99%, more preferably 98%, for example. Examples of the crystal structure of the cellulose component include type I, type II, type III, and type IV, and among them, from the viewpoint of reinforcing the resin, it is a cellulose component having a type I crystal structure having a high elastic modulus. Is preferable.

Cellulose fibers contained in pulp are usually 10 to 100 μm in diameter, but the cellulose used in the present invention is preferably finely divided into fibers having a diameter of 1 to 10 μm in the circumferential cross section, and cellulose nano. It is more preferably fiber. More specifically, cellulose nanofibers having a diameter of 3 to 1000 nm are more preferable, and cellulose nanofibers having a diameter of 3 to 100 nm are even more preferable. However, not all of them need to be miniaturized, and some of them may be used. In this specification, the diameter of cellulose or cellulose nanofibers is defined as the median diameter obtained by SEM observation of 50 or more randomly extracted cellulose nanofibers.

In general, it is considered that cellulose is ideally miniaturized without impairing its length, crystallinity, and degree of polymerization, and the strength of the obtained resin composition is exhibited when it is ideally dispersed. However, in reality, it is assumed that the thinner and longer the nanofibers are, the more they aggregate and the strength of the resin composition cannot be obtained. Further, since there are cases where the length, crystallinity, and degree of polymerization of the nanofibers are reduced by miniaturizing to the nano size, the appropriate degree of miniaturization differs depending on the purpose and the means for miniaturization.

As a method for refining cellulose, a known method can be widely adopted, and there is no particular limitation. Specifically, physical methods such as a high-pressure homogenizer method, an underwater counter-collision method, a grinder method, a ball mill method, and a biaxial kneading method may be used, and chemistry using a TEMPO catalyst, phosphoric acid, dibasic acid, sulfuric acid, hydrochloric acid, or the like may be used. Method may be used. Normally, the diameter of nanofibers is 10 to 1000 nm by a physical method, but cellulose nanofibers having a diameter of 3 to 10 nm, which is finer by a chemical method, can be obtained. On the other hand, the smaller the diameter and the larger the aspect ratio, the higher the physical properties such as the strength of the obtained resin composition can be expected. It may not be possible.

(1.3. Aromatic epoxy resin layer)
The aromatic epoxy resin layer is provided by covering a part or the whole of the surface of the cellulose for the purpose of imparting hydrophobicity to the cellulose.

The aromatic epoxy resin layer is preferably composed of any aromatic epoxy resin, and more specifically, it preferably contains an aromatic epoxy compound. The aromatic epoxy compound preferably contains one or more benzene rings and one or more epoxy groups in its structural formula. However, when the resin composition described later is kneaded or the like, it reacts with both cellulose and the resin to form a crosslinked structure, and in order to obtain a high-strength resin composition, two aromatic epoxy compounds are used. It is preferable to have the above epoxy group.

Further, the aromatic epoxy compound preferably has a structure containing two or more aromatic rings in order to impart heat resistance to the composite and the resin composition, and the basic skeleton thereof includes a bisphenol structure and biphenol. Polycyclic aromatic structures such as structures and naphthalene structures are exemplified. Among them, polycyclic aromatic structures are preferable, and fluorene structures and bisarylfluorenes in which at least two aromatic rings are bonded to a fluorene structure are more preferable. This is because the fluorene structure has heat resistance, affinity with various resins and solvents, and hydrophobicity.

The aromatic epoxy compound having a fluorene structure preferably has a structure represented by the following formulas (1) and (2).

（式中、環Ｚはアレーン環、Ｘは下記式（２）で表わされる基を表わし、Ｒ^１及びＲ^２は、それぞれ、任意の置換基を表わし、ｎは１～３の整数、ｐは０以上の任意の整数、ｋは０～４の整数を表わす。）

(In the formula, ring Z represents an arene ring, X represents a group represented by the following formula (2), R ¹ and R ² each represent an arbitrary substituent, n is an integer of 1 to 3, and p is an integer of 1 to 3. Any integer greater than or equal to 0, k represents an integer from 0 to 4)

（式中、Ｒ^３はアルキレン基、ｍは０以上の任意の整数を表わす。）

(In the formula, R ³ represents an alkylene group and m represents an arbitrary integer of 0 or more.)

More specifically, 9,9-bis (glycisyloxyaryl) fluorene, for example, 9,9-bis (3-glycisyloxyphenyl) fluorene, 9,9-bis (4-glycisyloxy). 9,9-bis (glycisyloxy C _6-10 aryl) such as phenyl) fluorene, 9,9-bis (5-glycisyloxynaphthyl) fluorene, 9,9-bis (6-glycisyloxynaphthyl) fluorene, etc. Fluolene; 9,9-bis (glycisyloxy (poly) alkoxyaryl) fluorene, n = 1, p = k = 0, m2 = 1-5, eg, 9,9-bis (4- (2-glycisyl)). Oxyethoxy) phenyl) fluorene, 9,9-bis (4- (2-glycisyloxypropoxy) phenyl) fluorene, 9,9-bis (5- (2-glycisyloxyethoxy) naphthyl) fluorene, 9 , 9-bis (6- (2-glycisyloxyethoxy) naphthyl) fluorene, etc. 9,9-bis (glycisyloxy (poly) C _2-4 alkoxy C _6-10 aryl) fluorene; n = 1, p = For example, 9,9-bis (3-methyl-4-glycisyloxyphenyl) fluorene such as 9,9-bis (alkyl-glycisyloxyaryl) fluorene having 1, k = 0 and m2 = 0. 9,9-bis (C _1-4 alkyl-glycisyloxy C _6-10 aryl) fluorene; n = 1, p = 1, k = 0, m2 = 1-5 9,9-bis (alkyl-glycisyloxy (alkyl-glycisyloxy) Poly) alkoxyaryl) fluorene, for example 9,9-bis (C _1-4 alkyl-glycisyloxy (poly) such as 9,9-bis (3-methyl-4- (2-glycisyloxyethoxy) phenyl) fluorene. ) C _2-4 alkoxy C _6-10 aryl) fluorene; 9,9-bis (aryl-glycisyloxyaryl) fluorene with n = 1, p = 0, k = 0, m2 = 0, eg 9 9,9-bis (C _6-10 aryl-glycisyloxy C _6-10 aryl) fluorene such as 9-bis (4-phenyl-3-glycisyloxyphenyl) fluorene; n = 1, p = 0, k = 0, m2 = 1-5 9,9-bis (aryl-glycisyloxy (poly) alkoxyaryl) fluorene, for example 9,9-bis (4-phenyl-3- (2-glycisyloxyethoxy)) 9,9-bis (C6-10aryl-glycisyloxy) such as phenyl) fluorene (Poly) C _2-4 alkoxy C _6-10 aryl) fluorene; 9,9-bis (di (glycisyloxy) aryl) fluorene with n = 2, p = 0, k = 0, m2 = 0, eg, 9 , 9-bis (3,4-di (glycisyloxy) phenyl) fluorene and other 9,9-bis (di (glycisyloxy) C _6-10 aryl) fluorene; n = 2, p = 0, k = 0, m2 = 1,9-bis (di (glycisyloxy (poly) alkoxy) aryl) fluorene which is 1 to 5, for example, 9,9-bis (3,4-di (2-glycisyloxyethoxy)) phenyl) fluorene and the like. 9,9-Bis (di (glycisyloxy (poly) C _2-4 alkoxy) C _6-10 aryl) fluorene and the like can be exemplified. These fluorene compounds can be used alone or in combination of two or more.

The fluorene epoxy compound having a group represented by the formula (2) may be a monomer or a multimer (for example, a dimer, a trimer, etc.). The fluorene compound having a glycidyl group usually contains at least a monomer, and may be, for example, a mixture of a monomer, a dimer and a trimer.

Further, the content of the aromatic epoxy compound in the complex is preferably 2 to 100 parts by mass, more preferably 5 to 75 parts by mass with respect to 100 parts by mass of cellulose (in terms of solid component). preferable. By adopting such a configuration, it is possible to improve the efficiency of the cross-linking reaction between celluloses by epoxy while preventing the aggregation of celluloses by inhibiting the hydrogen bonds between the celluloses.

The thickness of the aromatic epoxy resin layer is not particularly limited, but is preferably 1 to 1000 nm, for example.

The aromatic epoxy resin layer may be an aliphatic epoxy, an epoxy resin curing agent, an effect promoter, an inorganic metal oxide, and a carbon material in addition to the above aromatic epoxy compounds, depending on the purpose of use of the composite and the resin composition. It may further contain one or more additives selected from the group consisting of.

The complex of the present invention as described above can be obtained, for example, by dissolving an aromatic epoxy compound in an organic solvent, adding cellulose to the organic solvent, and kneading the compound.

(2. Composition)
The composition of the present invention is preferably composed by containing the complex of the present invention in an organic solvent.

(2.1. Organic solvent)
As the organic solvent, a known organic solvent can be widely used, but the boiling point is 110 in order to prevent water from agglomerating while preventing the aggregation of cellulose when obtaining the resin composition described later. It is preferable to use an organic solvent having a temperature of ° C or higher. On the other hand, from the viewpoint of making it possible to easily remove such an organic solvent, it is preferable to use an organic solvent having a boiling point of 250 ° C. or lower.

In addition, when kneading with a hydrolyzable resin in a state containing an organic solvent, if kneading with a hydrolyzable resin is assumed for the reason of avoiding arcolisis, an organic having no hydroxyl group is expected. It is preferable to use a solvent.

More specifically, the organic solvent includes both alcohol-based, ketone-based, glycol-based, lactone-based, lactam-based, amide-based, sulfoxide-based, ether-based solvents, etc., which have an affinity for both water and aromatic epoxy. It is preferable to use an organic solvent that is an amphoteric substance. Further, considering that the composition is kneaded with the solvent remaining, a group consisting of a ketone type, a glycol type having both ends etherified and having no hydroxyl group, a lactone type, a lactam type, an amide type, and a sulfoxide type. It is preferable to use one or more organic solvents selected from the above.

(2.2. Water)
The composition may further contain water in addition to the organic solvent to prevent the aggregation of cellulose. The water content is preferably 0.1 to 10% by mass in 100% by mass of the composition.

(3. Resin composition)
It is also preferable to prepare a resin composition containing the complex and the resin of the present invention. Such a resin composition is superior in strength and elastic modulus after curing as compared with a resin composition containing no complex.

(3.1. Resin)
As the resin to be used, it is preferable to use at least one selected from the group consisting of polyester-based resin, polyamide-based resin, and polycarbonate-based resin because it has reactivity with epoxy resin. Further, since it is preferable to increase the biomass ratio from the viewpoint of environmental friendliness, it is preferable to use one or more selected from the group consisting of biomass plastics and microbially produced plastics.

Rubber or thermoplastic elastomers may be used because of the high modulus of elasticity of cellulose. Examples of the rubber include diene rubber, olefin rubber, acrylic rubber, butyl rubber, epichlorohydrin rubber, silicone rubber, polysulfide rubber, fluororubber, etc., and diene rubber and olefin rubber from the viewpoint of compatibility. Is preferable. Examples of the thermoplastic elastomer include styrene-based, olefin-based, ester-based, urethane-based, amide-based, polyvinyl chloride-based, and fluorine-based, and olefin-based, ester-based, and amide-based are preferable from the viewpoint of compatibility.

More specifically, one or more selected from the group consisting of polylactic acid, polyamide 4, polyamide 11, polybutylene succinate, polyhydroxybutyrate, and a copolymer containing these structures may be used. preferable.

The diene rubber is preferably styrene-butadiene rubber, isoprene rubber, butadiene rubber, chloroprene rubber, and acrylonitrile-butadiene rubber, and the olefin rubber is preferably ethylene-propylene rubber or ethylene-propylene-diene rubber.
The thermoplastic elastomer preferably has a polyethylene structure, a polypropylene structure, a butadiene structure, a polyethylene terephthalate structure, a polyamide 6 structure, a polyamide 66 structure, a polyamide 11 structure, and a polyamide 12 structure, and is a styrene-ethylene-butylene-styrene copolymer. , Styrene-butadiene-styrene copolymer, styrene-butylene-butadiene-styrene copolymer, etc. may contain a styrene structure which is another system while having an olefin structure or a diene structure.

The resin composition of the present invention is obtained by mixing (evaporating) the organic solvent and water by mixing the resin with the above-mentioned composite, which is composed of the organic solvent and the composite, and heating or the like. be able to.

(4. Method for manufacturing complex)
The method for producing a composite of the present invention is a method for producing a composite having cellulose and an aromatic epoxy resin layer covering a part or the whole of the surface of the cellulose, and the cellulose is combined with an aromatic epoxy compound. It is characterized by having a step 1 of adding a solution for forming an aromatic epoxy resin layer containing an organic solvent and an organic solvent.

As for cellulose, aromatic epoxy compounds, and organic solvents, those described above can be used.

As a method of adding an aromatic epoxy resin layer forming solution containing an aromatic epoxy compound and an organic solvent to cellulose, it is preferable to mix all of them. As a more specific embodiment of such a mixing operation, it may be melt-kneading or mixing via an organic solvent. Above all, by adopting melt-kneading, not only the productivity can be improved, but also the dispersibility of the complex becomes good.

Further, the aromatic epoxy resin layer forming solution further contains water, and after the step 1, the step of removing the water in the aromatic epoxy resin layer forming solution by heating and / or depressurizing. You may have 2.

The heating operation can be widely adopted by a known method, and is not particularly limited. Specifically, it is possible to adopt a method of heating using a static hot air dryer, a vacuum dryer, a rotary evaporator, and a mixed dryer (conical dryer, nower dryer, etc.). .. The heating temperature condition is preferably set to 40 to 200 ° C, more preferably 60 to 150 ° C.

As for the depressurization operation, a known method can be widely adopted, and there is no particular limitation. Specifically, the pressure may be reduced by using a device such as an oil pump, an oilless pump, or an aspirator. The pressure condition in the depressurization operation is preferably set to 0.00001 to 0.05 MPa, more preferably 0.00001 to 0.03 MPa.

Although the embodiments of the present invention have been described above, the present invention is not limited to these examples, and it is needless to say that the present invention can be implemented in various forms without departing from the gist of the present invention.

Hereinafter, embodiments of the present invention will be described in more detail based on Examples, but the present invention is not limited thereto.

(Example 1)
30 g of cellulose nanofibers containing 50% or more of finely divided fibers having a diameter of 50 nm or less (Daicel FineChem Serish KY-110N, 200 g of water-wet body having a solid content of 15% by weight), 1800 g of diethylene glycol dimethyl ether and 15 g of bisphenol A epoxy ( 50 parts by mass of aromatic epoxy compound) was added to 100 parts by mass of cellulose nanofibers, and the mixture was stirred and then dried under reduced pressure at 80 ° C. to obtain 45 g of a composite. Then, 45 g of the complex and 255 g of polylactic acid (TE-2000 manufactured by Unitika) were melt-kneaded at 190 ° C. using a twin-screw extruder (Technobel 15 mmφ, L / D = 30) to obtain 250 g of a resin composition. rice field. The obtained resin composition was dried at 80 ° C. for 24 hours, and then used by an injection molding machine (Emerging Servic, C, MOBILE-0813) to have a length of 75 mm × a parallel portion width of 5 mm × a parallel portion length of 35. It was formed into a dumbbell test piece of mm × thickness of 2 mm.

(Example 2)
30 g of cellulose nanofibers containing 50% or more of finely divided fibers having a diameter of 50 nm or less (Daicel FineChem Serish KY-110N, 200 g of water-wet body with a solid content of 15% by weight), 1800 g of diethylene glycol dimethyl ether and 9,9-bis. 15 g (4-glycidyloxyphenyl) fluorene (BPFG) (50 parts by mass of aromatic epoxy compound with respect to 100 parts by mass of cellulose nanofibers) was added, stirred, and then dried under reduced pressure at 80 ° C. to obtain 45 g of a composite. rice field. Then, 45 g of the complex and 255 g of polylactic acid (TE-2000 manufactured by Unitika) were melt-kneaded at 190 ° C. using a twin-screw extruder (Technobel 15 mmφ, L / D = 30) to obtain 250 g of a resin composition. rice field. The obtained resin composition was dried at 80 ° C. for 24 hours, and then used by an injection molding machine (Emerging Servic, C, MOBILE-0813) to have a length of 75 mm × a parallel portion width of 5 mm × a parallel portion length of 35. It was formed into a dumbbell test piece of mm × thickness of 2 mm.

(Example 3)
1800 g of diethylene glycol dimethyl ether and 9,9-bis (4-glycidyloxy) are added to 30 g of cellulose nanofibers (150 g of water-wet body having a solid content of 20% by mass) containing 50% or more of fibers having a diameter of 100 nm or less defibrated by the grinder method. 15 g of phenyl) fluorene (BPFG) (50 parts by mass of aromatic epoxy compound with respect to 100 parts by mass of cellulose nanofibers) was added, stirred, and then dried under reduced pressure at 80 ° C. to obtain 45 g of a composite. Then, 45 g of the complex and 255 g of polylactic acid (TE-2000 manufactured by Unitika) were melt-kneaded at 190 ° C. using a twin-screw extruder (Technobel 15 mmφ, L / D = 30) to obtain 250 g of a resin composition. rice field. The obtained resin composition was dried at 80 ° C. for 24 hours, and then used by an injection molding machine (Emerging Servic, C, MOBILE-0813) to have a length of 75 mm × a parallel portion width of 5 mm × a parallel portion length of 35. It was formed into a dumbbell test piece of mm × thickness of 2 mm.

(Example 4)
1800 g of diethylene glycol dimethyl ether and 9,9-bis (4-glycidyloxy) are added to 30 g of cellulose nanofibers (150 g of water-wet body having a solid content of 20% by mass) containing 50% or more of fibers having a diameter of 100 nm or less defibrated by the grinder method. 15 g of phenyl) fluorene (BPFG) (50 parts by mass of aromatic epoxy compound with respect to 100 parts by mass of cellulose nanofibers) was added, and after stirring, the pressure was reduced at 80 ° C. to obtain 150 g of a solvent-moistened composite. Then, 150 g of the complex and 255 g of polylactic acid (TE-2000 manufactured by Unitika) were melt-kneaded at 190 ° C. using a twin-screw extruder (15 mmφ, L / D = 30 manufactured by Technobel) to obtain 250 g of a resin composition. rice field. The obtained resin composition was dried at 80 ° C. for 24 hours, and then used by an injection molding machine (Emerging Servic, C, MOBILE-0813) to have a length of 75 mm × a parallel portion width of 5 mm × a parallel portion length of 35. It was formed into a dumbbell test piece of mm × thickness of 2 mm.

(Example 5)
1800 g of diethylene glycol dimethyl ether and 9,9-bis (4-glycidyloxy) are added to 30 g of cellulose nanofibers (150 g of water-wet body having a solid content of 20% by mass) containing 50% or more of fibers having a diameter of 100 nm or less defibrated by the grinder method. 7.5 g of phenyl) fluorene (BPFG) (25 parts by mass of aromatic epoxy compound with respect to 100 parts by mass of cellulose nanofibers) was added, stirred, and then dried under reduced pressure at 80 ° C. to obtain 37.5 g of a composite. .. Then, 37.5 g of the composite and 262.5 g of polylactic acid (TE-2000 manufactured by Unitika) were melt-kneaded at 190 ° C. using a twin-screw extruder (15 mmφ, L / D = 30 manufactured by Technobel), and 250 g of resin was obtained. The composition was obtained. The obtained resin composition was dried at 80 ° C. for 24 hours, and then used by an injection molding machine (Emerging Servic, C, MOBILE-0813) to have a length of 75 mm × a parallel portion width of 5 mm × a parallel portion length of 35. It was formed into a dumbbell test piece of mm × thickness of 2 mm.

(Example 6)
1800 g of diethylene glycol dimethyl ether and 9,9-bis (4-glycidyloxy) are added to 30 g of cellulose nanofibers (150 g of water-wet body having a solid content of 20% by mass) containing 50% or more of fibers having a diameter of 100 nm or less defibrated by the grinder method. 7.5 g of phenyl) fluorene (BPFG) (25 parts by mass of aromatic epoxy compound with respect to 100 parts by mass of cellulose nanofibers) was added, and after stirring, the pressure was reduced at 80 ° C. to obtain 150 g of a solvent-moistened composite. .. Then, 150 g of the composite and 262.5 g of polylactic acid (TE-2000 manufactured by Unitika) were melt-kneaded at 190 ° C. using a twin-screw extruder (15 mmφ, L / D = 30 manufactured by Technobel), and 250 g of the resin composition was prepared. Got The obtained resin composition was dried at 80 ° C. for 24 hours, and then used by an injection molding machine (Emerging Servic, C, MOBILE-0813) to have a length of 75 mm × a parallel portion width of 5 mm × a parallel portion length of 35. It was formed into a dumbbell test piece of mm × thickness of 2 mm.

(Example 7)
1800 g of diethylene glycol dimethyl ether and 9,9-bis (4-glycidyloxy) are added to 30 g of cellulose nanofibers (150 g of water-wet body having a solid content of 20% by mass) containing 50% or more of fibers having a diameter of 100 nm or less defibrated by the grinder method. 3 g of phenyl) fluorene (BPFG) (10 parts by mass of aromatic epoxy compound with respect to 100 parts by mass of cellulose nanofibers) was added, and after stirring, the pressure was reduced at 80 ° C. to obtain 120 g of a solvent-moistened composite. Then, 120 g of the complex and 267 g of polylactic acid (TE-2000 manufactured by Unitika) were melt-kneaded at 190 ° C. using a twin-screw extruder (15 mmφ, L / D = 30 manufactured by Technobel) to obtain 250 g of a resin composition. rice field. The obtained resin composition was dried at 80 ° C. for 24 hours, and then used by an injection molding machine (Emerging Servic, C, MOBILE-0813) to have a length of 75 mm × a parallel portion width of 5 mm × a parallel portion length of 35. It was formed into a dumbbell test piece of mm × thickness of 2 mm.

(Comparative Example 1)
Polylactic acid (TE-2000 manufactured by Unitika) was melt-kneaded using a twin-screw extruder, dried at 80 ° C for 24 hours, and then used with an injection molding machine (Emerging Servic, C, MOBILE-0813). It was formed into a dumbbell test piece having a length of 75 mm, a width of the parallel portion of 5 mm, a length of the parallel portion of 35 mm, and a thickness of 2 mm.

(Comparative Example 2)
1800 g of diethylene glycol dimethyl ether is added to 30 g of cellulose containing 50% or more of finely divided fibers having a diameter of 50 nm or less (Daicel FineChem Serish KY-110N, 200 g of water-wet body having a solid content of 15% by weight), and then 80. Drying under reduced pressure at ° C. gave 30 g of cellulose. 30 g of the cellulose and 270 g of polylactic acid (TE-2000 manufactured by Unitika Ltd.) were kneaded at 190 ° C. to obtain 250 g of a resin composition. The obtained resin composition was dried at 80 ° C. for 24 hours, and then used by an injection molding machine (Emerging Servic, C, MOBILE-0813) to have a length of 75 mm × a parallel portion width of 5 mm × a parallel portion length of 35. It was formed into a dumbbell test piece of mm × thickness of 2 mm.

(Comparative Example 3)
1800 g of diethylene glycol dimethyl ether is added to 30 g of cellulose containing 50% or more of finely divided fibers having a diameter of 50 nm or less (Daicel FineChem Serish KY-110N, 200 g of water-wet body having a solid content of 15% by weight), and then 80. The pressure was reduced at ° C. to obtain 150 g of solvent-moistened cellulose. A wet product containing 30 g of the cellulose and 270 g of polylactic acid (TE-2000 manufactured by Unitika Ltd.) were kneaded at 190 ° C. to obtain 250 g of a resin composition. The obtained resin composition was dried at 80 ° C. for 24 hours, and then used by an injection molding machine (Emerging Servic, C, MOBILE-0813) to have a length of 75 mm × a parallel portion width of 5 mm × a parallel portion length of 35. It was formed into a dumbbell test piece of mm × thickness of 2 mm.

(Comparative Example 4)
It is a diethylene glycol dimethyl ether 1800 g and a non-epoxy fluorene compound in 30 g of cellulose containing 50% or more of finely divided fibers having a diameter of 50 nm or less (Daicel FineChem Serish KY-110N, 200 g of a water-wet body having a solid content of 15% by weight). 15 g of 9,9-bisphenoxyethanol fluorene (BPEF) was added, the mixture was stirred, and then dried under reduced pressure at 80 ° C. to obtain 45 g of a complex. 45 g of the complex and 255 g of polylactic acid (TE-2000 manufactured by Unitika Ltd.) were kneaded at 190 ° C. to obtain 250 g of a resin composition. The obtained resin composition was dried at 80 ° C. for 24 hours, and then used by an injection molding machine (Emerging Servic, C, MOBILE-0813) to have a length of 75 mm × a parallel portion width of 5 mm × a parallel portion length of 35. It was formed into a dumbbell test piece of mm × thickness of 2 mm.

(Comparative Example 5)
1800 g of diethylene glycol dimethyl ether and a non-epoxy fluorene compound are added to 30 g of cellulose containing 50% or more of finely divided fibers having a diameter of 50 nm or less (Daicel FineChem Serish KY-110N, 200 g of water-wet body having a solid content of 15% by weight). After adding 15 g of 9,9-bisphenoxyethanol fluorene (BPEF) and stirring, the pressure was reduced at 80 ° C. to obtain a complex of 150 g wet with a solvent. 180 g of the complex and 255 g of polylactic acid (TE-2000 manufactured by Unitika Ltd.) were kneaded at 190 ° C. while removing the solvent to obtain 250 g of a resin composition. The obtained resin composition was dried at 80 ° C. for 24 hours, and then used by an injection molding machine (Emerging Servic, C, MOBILE-0813) to have a length of 75 mm × a parallel portion width of 5 mm × a parallel portion length of 35. It was formed into a dumbbell test piece of mm × thickness of 2 mm.

(Comparative Example 6)
30 g of cellulose containing 50% or more of finely divided fibers having a diameter of 50 nm or less (Daicel FineChem's Serish KY-110N, 200 g of water-wet body with a solid content of 15% by mass) and 9,9-bis, which is an epoxy-based fluorene compound ( 4-Glycidyloxyphenyl) Fluolene (BPFG) is chemically bonded to 10% by mass (mass derived from BPFG component is 10% by mass with respect to cellulose mass), and 150 g of a material moistened with diethylene glycol dimethyl ether and polylactic acid (manufactured by Unitica). TE-2000) 267 g was kneaded at 190 ° C. to obtain 250 g of a resin composition.

(Tensile strength, tensile elasticity test)
Tensile tests were performed on the obtained test pieces of Examples and Comparative Examples using a universal material testing machine (Instron 5567) at an atmospheric temperature of 23 ° C and a tensile speed of 10 mm / min n = 5, and the tensile strength and tensile strength were obtained. The elastic modulus was calculated. The obtained results are shown in Table 1 below.

As shown in Table 1, it was confirmed that the test pieces of each example were superior in strength to the test pieces of each comparative example.

Claims (2)

A method for producing a composite having cellulose and an aromatic epoxy resin layer that does not chemically modify the cellulose that covers a part or the whole of the surface of the cellulose.
Step A to obtain a water-wet body of cellulose by adding only water to the cellulose and defibrating it, and
A step B of adding an aromatic epoxy resin layer forming solution containing an aromatic epoxy compound and an organic solvent to the water-wet body is provided in this order .
A production method, wherein the aromatic epoxy compound contained in the aromatic epoxy resin layer has a fluorene structure. The production method according to claim 1, further comprising a step C of removing water in the aromatic epoxy resin layer forming solution by heating and / or reducing the pressure after the step B.