JP2019119867A - Fine cellulose fiber composite dispersion - Google Patents

Abstract

An object of the present invention is to provide a dispersion in which the dispersibility of cellulose fibers in an organic liquid compound is improved.
Kind Code: A1 A finely divided cellulose fiber comprising a finely divided cellulose fiber composite in which an amine is bonded via an ionic bond to an anionic group of an anionically modified cellulose fiber containing an anionic group, a dispersant, and an organic liquid compound. Complex dispersion.
【Selection chart】 None

Description

  The present invention relates to a fine cellulose fiber composite dispersion.

  In the past, petroleum-derived plastic materials, which are limited resources, were widely used, but in recent years, technology with less impact on the environment has come to be highlighted, and under such technological background, biomass is naturally abundant Materials using cellulose fibers are attracting attention. For example, the mechanical strength etc. of the material obtained can be improved by mix | blending with resin etc. the dispersion liquid which the cellulose fiber disperse | distributed to various media.

  For example, Patent Document 1 discloses that when a fine cellulose fiber composite formed by bonding an amine having an ethylene oxide / propylene oxide copolymer moiety as a salt to a carboxy group of fine cellulose fiber as a salt is mixed with a resin, It has been shown that it is possible to provide a resin composition that is excellent in mechanical strength.

  Further, for example, in Patent Document 2, heat resistance, mechanical strength, and the like are obtained when a fine cellulose fiber composite, in which an aromatic hydrocarbon group is connected to fine cellulose fibers via an ionic bond and introduced, is mixed with a resin. It is shown that a resin composition excellent in transparency can be provided.

JP, 2015-143336, A JP, 2016-156111, A

  In recent years, further improvement in mechanical strength of various resin products is required, and therefore, further improvement of the technology for highly dispersing cellulose fibers in an organic liquid compound is desired.

  The present invention relates to a dispersion in which the dispersibility of cellulose fibers in an organic liquid compound is improved.

That is, the present invention relates to the following [1] to [3].
[1] A fine cellulose fiber composite comprising a fine cellulose fiber complex in which an amine is bonded via an ionic bond to an anionic group of an anionically modified cellulose fiber containing an anionic group, a dispersant, and an organic liquid compound Body dispersion.
[2] The fine cellulose fiber composite dispersion as described in the above [1], further containing a resin.
[3] A resin molded product obtained by molding the fine cellulose fiber composite dispersion described in [2].

  The dispersion liquid of the present invention has an effect that the dispersibility of the cellulose fiber to the organic liquid compound is improved.

<Fine cellulose fiber composite dispersion>
The fine cellulose fiber composite dispersion of the present invention comprises a fine cellulose fiber composite, a dispersant, and an organic liquid compound.

  As a result of investigations by the present inventors about the dispersibility, the improvement of the dispersibility was not seen only by mixing the fine cellulose fiber and the dispersing agent, but surprisingly, the amine is bound to the anionic group as a salt. It has been found that the dispersibility with respect to the organic liquid compound is improved by mixing the fine cellulose fiber composite and the dispersing agent. Although the detailed reason is unknown, it is considered that the addition of the dispersing agent increases the compatibility between the fine cellulose fiber composite and the organic liquid compound and improves the dispersibility.

  The viscosity of the dispersion of the present invention is not particularly limited, and from the viewpoint of handleability, the lower the better, the better. For example, the viscosity at 25 ° C. of the dispersion is preferably 50,000 mPa · s or less, more preferably 10,000 mPa · s or less. Specifically, the viscosity of the dispersion is measured by the method described in the examples below.

  Since the dispersion liquid of this invention is excellent in the dispersibility with respect to the organic liquid compound, it can be utilized as an improvement agent of the mechanical strength of various resin products, for example.

[Fine cellulose fiber composite]
The fine cellulose fiber composite used in the present invention is a fine cellulose fiber in which an amine is bonded to a cellulose fiber (anion-modified cellulose fiber) containing an anionic group via an ionic bond. The fine cellulose fiber composite used in the present invention is a step of introducing an anionic group into a raw material cellulose fiber to obtain an anion-modified cellulose fiber containing an anionic group (step of introducing an anionic group: step A), an anion It can manufacture by performing the process (process of introduce | transducing an amine: process B) of introduce | transducing an amine into the anion-modified cellulose fiber containing a property group, and a refinement | miniaturization process process (process C). In addition, a refinement | miniaturization process process may be implemented between process A and process B, and may be implemented in multiple times.

(Cellulose fiber)
As a raw material cellulose fiber, it is preferable to use natural cellulose fiber from an environmental load viewpoint. Examples of natural cellulose fibers include wood pulp such as softwood pulp and hardwood pulp; cotton pulp such as cotton linters and cotton lint; non-wood pulp such as straw pulp and bagasse pulp; bacterial cellulose and the like These 1 type can be used individually or in combination of 2 or more types.

  The average fiber diameter of the raw material cellulose fiber is not particularly limited, but is preferably 5 μm or more, more preferably 7 μm or more from the viewpoint of handleability and cost, and preferably 500 μm or less from the same viewpoint. Preferably it is 300 micrometers or less.

  The average fiber length of the raw material cellulose fiber is not particularly limited, but is preferably 1,000 μm or more, more preferably 1,500 μm or more from the viewpoint of availability and cost, and from the same viewpoint, preferably 5, It is not more than 000 μm, more preferably not more than 3,000 μm. The average fiber diameter and the average fiber length of the raw material cellulose fiber can be measured according to the method described in the following examples.

(Anion-modified cellulose fiber containing an anionic group)
The anion-modified cellulose fiber containing an anionic group (also simply referred to as "anion-modified cellulose fiber") used in the present invention is a cellulose fiber anion-modified so as to contain an anionic group in the cellulose fiber.

  As an anionic group, a carboxy group, a sulfonic acid group, a phosphoric acid group etc. are mentioned, for example. It is preferably a carboxy group from the viewpoint of the introduction efficiency to cellulose fiber. The anionic group may be introduced alone or in combination of two or more. In addition, the ion (counter ion) used as the pair of anionic group is preferably a proton.

  The content of the anionic group in the anion-modified cellulose fiber is preferably 0.1 mmol / g or more, more preferably 0.4 mmol / g or more, from the viewpoint of stable miniaturization and amine introduction. Preferably it is 0.6 mmol / g or more. The upper limit thereof is preferably 3.0 mmol / g or less, more preferably 2.0 mmol / g or less, and still more preferably 1.8 mmol / g or less. Anionic group content means the total amount of the anionic group in the cellulose fiber which comprises anionic group containing cellulose fiber. The content of the anionic group is measured by the method described in the examples below.

  From the same point of view, the content of the hydroxyl group in the anion-modified cellulose fiber is preferably 0.5 mmol / g or more, more preferably 1.0 mmol / g or more, still more preferably 2.0 mmol / g or more It is. The upper limit thereof is preferably 20 mmol / g or less, more preferably 19 mmol / g or less, and still more preferably 18 mmol / g or less. The content of the hydroxyl group of the anion-modified cellulose fiber can be calculated by measurement according to a known method (for example, titration, IR measurement, etc.).

  Although the preferable range of the average fiber diameter of an anion modified cellulose fiber and an average fiber length is based also on the order of a manufacturing process, it is equivalent to the thing of the cellulose fiber of a raw material.

(Step of Introducing Anionic Group: Step A)
The anion-modified cellulose fiber used in the present invention can be obtained by introducing an anionic group into the target cellulose fiber and subjecting it to anion modification. For example, the cellulose fiber of the target raw material is subjected to oxidation treatment or addition of an anionic group A treatment can be performed to introduce an anionic group.

(i) When introducing a carboxy group as an anionic group into a cellulose fiber As a method of introducing a carboxy group into a cellulose fiber, for example, a method of oxidizing a hydroxyl group of cellulose to convert it into a carboxy group And at least one selected from the group consisting of acid anhydrides of compounds having a carboxy group and derivatives thereof.

  The method for oxidizing the hydroxyl group of cellulose is not particularly limited. For example, sodium hypochlorite using a catalyst such as 2,2,6,6-tetramethyl-1-piperidine-N-oxyl (TEMPO) as a catalyst A method of reacting by oxidizing an oxidizing agent and a bromide such as sodium bromide can be applied. In more detail, the method of Unexamined-Japanese-Patent No. 2011-140632 can be referred to.

By performing oxidation treatment of cellulose fibers using TEMPO as a catalyst, the hydroxymethyl group (-CH ₂ OH) at the C6 position of the cellulose structural unit is selectively converted to a carboxy group. In particular, this method is advantageous in that it is excellent in the selectivity of the hydroxyl group at the C6 position to be oxidized on the surface of the raw material cellulose fiber, and the reaction conditions are also mild. Therefore, a preferred embodiment of the anion-modified cellulose fiber in the present invention is a cellulose fiber in which the C6 position of the cellulose structural unit is a carboxy group. In the present specification, such cellulose fibers may be referred to as "oxidized cellulose fibers".

  Although the compound which has a carboxy group for using for introduce | transducing a carboxy group to a cellulose fiber is not specifically limited, Specifically, a halogenated acetic acid is mentioned. Chloroacetic acid etc. are mentioned as halogenated acetic acid.

  Acid anhydrides of compounds having a carboxy group and derivatives thereof for use in introducing a carboxy group into a cellulose fiber are not particularly limited, and maleic anhydride, succinic anhydride, phthalic anhydride and adipic anhydride etc. Examples thereof include acid anhydrides of dicarboxylic acid compounds, imidates of acid anhydrides of compounds having a carboxy group, and derivatives of acid anhydrides of compounds having a carboxy group. These compounds may be substituted by hydrophobic groups.

(ii) When introducing a sulfonic acid group or a phosphoric acid group as an anionic group into a cellulose fiber As a method of introducing a sulfonic acid group into a cellulose fiber, a method of adding sulfuric acid to a cellulose fiber and heating it can be mentioned.

  As a method of introducing a phosphate group into cellulose fiber, a method of mixing phosphoric acid or a powder or aqueous solution of phosphoric acid with cellulose fiber in a dry or wet state, or a dispersion of cellulose fiber with phosphoric acid or phosphoric acid The method of adding the aqueous solution of a derivative etc. are mentioned. When these methods are employed, generally, after mixing or adding phosphoric acid or a powder or aqueous solution of a phosphoric acid derivative, dehydration treatment, heat treatment and the like are performed.

  By introducing an anionic group into the cellulose fiber by any of the methods described above, the raw material cellulose fiber is anion-modified to become an anion-modified cellulose fiber. At this point, the miniaturization process has not been performed. From the viewpoint of improving the thermal dimensional stability and mechanical strength of the fiber of the present invention, it is preferable to further carry out a reduction treatment and a low aspect ratio treatment.

(Anion modified cellulose fiber complex)
The anion-modified cellulose fiber complex in the present invention is a cellulose fiber formed by bonding an amine to an anionic group of anion-modified cellulose fiber via an ionic bond. In the present specification, "an amine is bonded to an anionic group through an ionic bond" means that the anionic group, for example, a carboxy group is deprotonated and the amine becomes an ammonium salt, and both are ionically bonded. Means

(Amine)
Examples of amines include primary amines, secondary amines and tertiary amines. In these amines, various hydrocarbon groups such as a chain saturated hydrocarbon group, a chain unsaturated hydrocarbon group, a cyclic saturated hydrocarbon group, an aromatic hydrocarbon group, etc. as a modification group to an anionic group These hydrocarbon groups, copolymerization sites, etc. can be introduced. These groups and sites may be introduced alone or in combination of two or more.

  The primary amine to tertiary amine preferably have 3 or more carbon atoms, more preferably 6 or more carbon atoms from the viewpoint of dispersibility, and more preferably 30 or less carbon atoms from the same viewpoint. More preferably, it is 24 or less, More preferably, it is 18 or less. Specific examples of the primary to tertiary amines include propylamine, dipropylamine, butylamine, dibutylamine, hexylamine, 2-ethylhexylamine, dihexylamine, trihexylamine, octylamine, dioctylamine and trioctylamine. Examples include amines, dodecylamine, didodecylamine, distearylamine, oleylamine, aniline, octadecylamine and dimethylbehenylamine. Among these, from the viewpoint of dispersibility, hexylamine, 2-ethylhexylamine, dihexylamine, trihexylamine, dodecylamine and oleylamine are preferable.

  When the amine is an amine having a chain saturated hydrocarbon group described above, the chain saturated hydrocarbon group may be linear or branched. The carbon number of the chain saturated hydrocarbon group is preferably 3 or more, more preferably 4 or more, and still more preferably 6 or more as the carbon number in one amine from the viewpoint of improving the dispersibility. From the same viewpoint, it is preferably 30 or less, more preferably 24 or less, and still more preferably 18 or less. Specifically, hexyl group, 2-ethylhexyl group, dodecyl group, dihexyl group, trihexyl group etc. are mentioned.

  When the amine is an amine having a chain unsaturated hydrocarbon group as described above, the chain unsaturated hydrocarbon group may be linear or branched. The carbon number of the chain unsaturated hydrocarbon group is preferably 3 or more, more preferably 4 or more, and still more preferably 6 or more as the carbon number in one amine from the viewpoint of improving the dispersibility. From the same point of view, it is preferably 30 or less, more preferably 24 or less, and still more preferably 18 or less. An oleyl group etc. are mentioned specifically ,.

  When the amine is an amine having a cyclic saturated hydrocarbon group, the carbon number of the cyclic saturated hydrocarbon group is preferably 3 or more as the carbon number of one amine, from the viewpoint of improving the dispersibility. More preferably, it is 4 or more, more preferably 6 or more, and from the same viewpoint, preferably 30 or less, more preferably 24 or less, and still more preferably 18 or less.

  When the amine is an amine having an aromatic hydrocarbon group, the aromatic hydrocarbon group is preferably at least 6 as a carbon number of one amine from the viewpoint of improving the dispersibility, and from the same viewpoint, preferably It is 30 or less, more preferably 24 or less, still more preferably 18 or less, still more preferably 14 or less, still more preferably 10 or less.

  When the amine has a hydrocarbon group and the hydrocarbon group has a substituent, for example, a straight chain having 1 to 6 carbon atoms or a carbon having 1 to 6 carbons as a substituent, provided that the number of carbons in the amine satisfies the above range. Branched alkoxy group; linear or branched alkoxycarbonyl group having 1 to 6 carbon atoms of alkoxy group; halogen atoms such as bromine atom, iodine atom; acyl group having 1 to 6 carbon atoms; aralkyl group; aralkyloxy group A C1-C6 alkylamino group; an alkyl group having a C1-C6 dialkylamino group, a hydroxyl group, an ether, an amide or the like may be used. In addition, the various hydrocarbon groups described above may be bonded to another hydrocarbon group as a substituent.

  The various primary amines, secondary amines and tertiary amines described above can be commercially available products and can be prepared according to known methods.

(Amine having a copolymerization site)
In the fine cellulose fiber composite in the present invention, the amine to be bound can contain a copolymerization site. As such a copolymerization site, for example, an ethylene oxide / propylene oxide (EO / PO) copolymerization site can be used. The EO / PO copolymerization site means a structure in which ethylene oxide (EO) and propylene oxide (PO) are randomly or block-polymerized.

  The content (mol%) of PO in the EO / PO copolymerization site is preferably 1 mol% or more, more preferably 5 mol% or more, still more preferably 10 mol% or more from the viewpoint of improving the dispersibility. It is. From the same viewpoint, it is preferably 90 mol% or less, more preferably 60 mol% or less, and still more preferably 40 mol% or less.

  The molecular weight of the EO / PO copolymer site is preferably 500 or more, more preferably 1,000 or more, and still more preferably 1,500 or more from the viewpoint of improving the dispersibility. From the same viewpoint, it is preferably 10,000 or less, more preferably 5,000 or less, and still more preferably 3,500 or less.

  When the amine is an amine having an EO / PO copolymerization site and an amino group, the EO / PO copolymerization site and the amino group may be bonded directly or via a linking group. It is also good. As the linking group, for example, a hydrocarbon group is preferable, and an alkylene group having a carbon number of preferably 1 or more and 6 or less, more preferably 1 or more and 3 or less is used. As an alkylene group, an ethylene group and a propylene group are preferable, for example.

  As an amine (It is also called "EOPO amine") which has an EO / PO copolymerization site | part, the compound represented, for example by following formula (i) is mentioned.

[Wherein, R ₁ represents a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms, EO and PO are present in a random or block shape, and a is a positive average molar number of EO] And b is a positive number representing the average added mole number of PO]

  A in the formula (i) represents the average addition mole number of EO, and is preferably 1 or more, more preferably 15 or more, and still more preferably 30 or more from the viewpoint of further improving the dispersibility. From the same viewpoint, it is preferably 100 or less, more preferably 70 or less, and still more preferably 50 or less.

  B in formula (i) represents the average addition mole number of PO, and from the viewpoint of further improving the dispersibility, it is preferably 3 or more, more preferably 5 or more. From the same viewpoint, it is preferably 50 or less, more preferably 30 or less.

  When the amine is represented by the formula (i), the content (mol%) of PO in the EO / PO copolymer site can be calculated based on the a and b, specifically, It can be determined from b × 100 / (a + b). The preferred range of the content of PO is as described above.

R ₁ in the formula (i) is preferably a hydrogen atom from the viewpoint of improving the dispersibility. When R ₁ is a linear or branched alkyl group having 1 to 6 carbon atoms, the alkyl group is preferably a methyl group, an ethyl group, an n-propyl group and a sec-propyl group.

  The detail about the amine which has an EO / PO copolymerization site | part represented by Formula (i) is described, for example in the patent 6105139.

  The average bonding amount of the amine in the anion-modified cellulose fiber composite is preferably 0.01 mmol / g or more, more preferably 0.05 mmol / g or more, and still more preferably 0. It is 1 mmol / g or more, more preferably 0.3 mmol / g or more, and further preferably 0.5 mmol / g or more. Also, from the viewpoint of reactivity, it is preferably 3 mmol / g or less, more preferably 2.5 mmol / g or less, still more preferably 2 mmol / g or less, and still more preferably 1.8 mmol / g or less. More preferably, it is 1.5 mmol / g or less. When any two or more amines are simultaneously introduced into the cellulose fiber as the amine, the average bonding amount of the amines is preferably such that the total amount of amines introduced is within the above range.

  From the viewpoint of dispersibility, the amine introduction rate in the anion-modified cellulose fiber composite is preferably 5% or more, more preferably 10% or more, and still more preferably 15% or more from the viewpoint of dispersibility. From the viewpoint of reactivity, it is preferably 100% or less, more preferably 60% or less, and still more preferably 50% or less.

  In the present specification, the average binding amount and introduction rate of the amine can be adjusted by the addition amount of the amine, the type of the amine, the reaction temperature, the reaction time, the solvent and the like. The average bound amount (mmol / g) and the introduction rate (%) of the amine are the amount and ratio of the amine introduced to the anionic group of the surface of the anion-modified cellulose fiber. The anionic group content and the hydroxyl group content of the anion-modified cellulose fiber can be calculated by measurement according to a known method (for example, titration, IR measurement, etc.). The average binding amount and the introduction rate of the amine are calculated, for example, by the method described in the examples.

  Although the preferable range of the average fiber diameter of an anion modified cellulose fiber composite and an average fiber length is based also on the order of a manufacturing process, it is equivalent to the thing of the cellulose fiber of a raw material.

(Step of introducing amine: Step B)
The anion-modified cellulose fiber composite used in the present invention can be produced according to a known method without particular limitation, as long as an amine can be introduced into the anion-modified cellulose fiber containing the above-described anionic group.

  For example, as shown below, an aspect (aspect A) in which an amine is bound to an anion modified cellulose fiber by an ionic bond is mentioned.

(Aspect A): A step of mixing an amine with a carboxy group-modified cellulose fiber as an anion-modified cellulose fiber (step B1).
As a specific method in which the anionic group is a carboxy group, the embodiment A can be carried out with reference to the method described in step (B) of JP-A-2015-143336.

[Fine cellulose fiber composite]
The fine cellulose fiber composite used in the present invention is a fine cellulose fiber in which an amine is bonded to a cellulose fiber (anion-modified cellulose fiber) containing an anionic group via an ionic bond. Specifically, the fine cellulose fiber composite can be produced by performing the above-described step A, step B, and step C described later.

  The fine cellulose fiber composite used in the present invention has a cellulose type I crystal structure due to the use of natural cellulose fibers as a raw material. The cellulose type I is a crystal form of natural cellulose, and the cellulose type I crystallinity means the ratio of the amount of crystalline region to the whole cellulose.

  The degree of crystallinity of the fine cellulose fiber composite in the present invention is preferably 30% or more, more preferably 35% or more, still more preferably 40% or more, from the viewpoint of exhibiting the effects of the present invention. More preferably, it is 45% or more. Further, from the viewpoint of the cost of the raw material for cellulose used, it is preferably 95% or less, more preferably 90% or less, still more preferably 85% or less, and still more preferably 80% or less. In addition, in this specification, the crystallinity degree of the cellulose in this invention is specifically measured by the method as described in the below-mentioned Example.

  The fine cellulose fiber composite preferably has an average fiber diameter of 0.1 nm or more, more preferably 0.5 nm or more, still more preferably 1 nm or more, still more preferably 2 nm or more, from the viewpoint of exhibiting the effects of the present invention. More preferably, it is 3 nm or more. From the same point of view, it is preferably 100 nm or less, more preferably 50 nm or less, still more preferably 20 nm or less, still more preferably 10 nm or less, still more preferably 6 nm or less, further preferably 5 nm or less. The average fiber diameter of the fine cellulose fiber composite can be measured by the method described in the examples.

  The average fiber length of the fine cellulose fiber composite is preferably 150 nm or more, more preferably 200 nm or more, from the viewpoint of exhibiting the effects of the present invention. From the same viewpoint, it is preferably 1000 nm or less, more preferably 750 nm or less, further preferably 500 nm or less, and further preferably 400 nm or less. The average fiber length of the fine cellulose fiber composite can be measured by the method described in the examples.

  The average aspect ratio of the fine cellulose fiber composite, that is, the value of fiber length / fiber diameter is preferably 1 or more, more preferably 10 or more, and still more preferably 20 or more, from the viewpoint of adhesion. The upper limit is preferably 40 or more, more preferably 50 or more, and the upper limit thereof is preferably 250 or less, more preferably 200 or less, still more preferably 150 or less, and still more preferably 100 or less. Preferably it is 90 or less. From the same viewpoint, when the average aspect ratio is in the above range, the standard deviation of the aspect ratio is preferably 60 or less, more preferably 50 or less, still more preferably 45 or less, and the lower limit is particularly set Although not preferred, it is preferably 4 or more from the viewpoint of economy. The average aspect ratio of the fine cellulose fiber composite can be measured by the method described in the examples.

  The fine cellulose fiber composite is a finely divided anion-modified cellulose fiber composite. Therefore, the preferable range of the fine cellulose fiber composite with respect to the average fiber diameter, the average bonding amount and introduction ratio of amines other than the average fiber length, and the type of amine is equivalent to that of the anion-modified cellulose fiber composite.

The content of the fine cellulose fiber composite in the dispersion liquid of the present invention is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, from the viewpoint of improving the mechanical strength of the product. More preferably, it is 0.5 mass% or more. On the other hand, from the viewpoint of cost effectiveness, it is preferably 3.0% by mass or less, more preferably 2.5% by mass or less, and still more preferably 2.0% by mass or less.
In addition, "containing" in this specification used for the dispersion liquid and resin molding of this invention can be read as "blending."

(Micronization process: Process C)
This step is a step of subjecting the anion-modified cellulose fiber composite obtained as described above to a refining treatment in an organic solvent, and a finely divided cellulose fiber composite is obtained by the refining treatment. In the refining treatment step, the anion-modified cellulose fiber complex obtained as described above is dispersed in an organic solvent, or the one obtained by removing the organic solvent is newly dispersed in a solvent. It is preferable to carry out a miniaturization process. Specifically, it can carry out with reference to description of the refinement | miniaturization process of Unexamined-Japanese-Patent No. 2013-151661.

Dispersant
Examples of the dispersant include nonionic surfactants such as alkyl imidazoline compounds and sorbitan fatty acid ester compounds. From the viewpoint of the dispersibility of the fine cellulose fiber composite in the dispersion, an alkyl imidazoline compound is preferable as the dispersant. A dispersing agent may use only 1 type and may use 2 or more types.

  Examples of the alkyl imidazoline dispersant include those in which an alkyl group is bonded to the nitrogen atom of at least one of the 1 or 3 nitrogen atoms in the imidazoline ring. Or what the alkyl group has couple | bonded with the carbon atom of at least one place among the 2nd, 4th or 5th carbon atoms in an imidazoline ring is mentioned. As the alkyl group, for example, the carbon number is preferably 2 or more, more preferably 6 or more, further preferably 10 or more, preferably 30 or less, more preferably 20 or less, still more preferably It is possible to use saturated or unsaturated groups which are 18 or less. Specifically, a saturated or unsaturated alkyl group having a carbon number of preferably 2 to 30, more preferably 6 to 20, and still more preferably 10 to 18 can be mentioned. When two or more alkyl groups are bonded to the imidazoline ring, the type of each alkyl group may be the same or different. Further preferred alkyl imidazoline dispersants are compounds in which the same or different carbon atoms are bonded to the 1- and 3-position nitrogen atoms in the imidazoline ring. The alkyl imidazoline dispersant is commercially available and thus readily available. Examples of commercially available products include Homogenol L-95 (manufactured by Kao Corporation) and propyl imidazoline (Tokyo Kasei Kogyo Co., Ltd.).

  The content of the dispersant in the dispersion liquid of the present invention is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, from the viewpoint of the dispersibility of the fine cellulose fiber composite in the dispersion liquid. More preferably, it is 1% by mass or more. On the other hand, it is preferably 50% by mass or less, more preferably 25% or less, still more preferably 20% by mass or less, still more preferably 10% by mass or less, from the viewpoint of cost effectiveness. It is 5% by mass or less.

[Organic liquid compound]
The organic liquid compound has a role as a dispersion medium for the fine cellulose fiber composite. The organic liquid compound is a liquid compound having an SP value of 10 or less, and preferably includes one or more oils selected from the group consisting of vegetable oil, animal oil, synthetic oil and liquid paraffin. In the present invention, only one type of organic liquid compound may be used, or two or more types may be used in combination.

The SP value in the present specification indicates the solubility parameter (unit: (cal / cm ³ ) ^1/2 ) calculated by the Fedors method, and, for example, the reference document “SP value basic / application and calculation method” (information mechanism (2005), Polymer handbook Third edition (A Wiley-Interscience publication, 1989), and the like.

  Vegetable oils are oils derived from plants, and specifically, rapeseed oil, peanut oil, corn oil, cottonseed oil, canola oil, soybean oil, sunflower oil, palm oil, palm oil, safflower oil, Camellia oil, olive oil, peanut oil etc. are mentioned.

  Examples of animal oils are oils derived from animals, and specific examples include lard, beef foot oil, sanagi oil, sardine oil, herring oil and the like.

  Synthetic oils include fatty acid esters, and specifically, medium-chain fatty acid triglyceride, diglycerin caprylic acid ester, diglycerin caprylic acid oleic acid ester, diglycerin oleic acid ester, decaglycerin oleic acid ester, decaglycerin oleic acid ester, deca Glycerin oleic acid ester etc. are mentioned. Also, synthetic oils other than fatty acid esters include silicone oils, normal paraffins, isoparaffins, polybutenes, polyisobutylenes, polyisobutylenes, 1-decene oligomers, poly α-olefins (PAO) such as copolymers of 1-decene and ethylene, and the like Hydrides and the like.

  The fatty acid constituting the fatty acid ester is preferably a fatty acid having 8 to 22 carbon atoms. Specifically, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, erucic acid, palmitolein Acids, oleic acid, linoleic acid, linolenic acid, isostearic acid, arachic acid, ricinoleic acid, 12-hydroxystearic acid and the like can be mentioned. Specific fatty acid esters include glycerin fatty acid esters, polyglycerin fatty acid esters, and propylene glycol fatty acid esters

  Examples of liquid paraffin include alicyclic hydrocarbon compounds having a branched structure and a ring structure represented by CmHn (m, n is an integer of 1 or more, but n <2m + 2), or a mixture thereof.

  The content of the organic liquid compound in the dispersion liquid of the present invention is preferably 70% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more from the viewpoint of dispersibility. . On the other hand, from the viewpoint of cost effectiveness, it is preferably 99% by mass or less, more preferably 98% by mass or less, and still more preferably 97% by mass or less.

[Production Method of Fine Cellulose Fiber Complex Dispersion]
The fine cellulose fiber composite dispersion of the present invention can be produced by mixing predetermined amounts of the fine cellulose fiber composite, the dispersing agent, and the organic liquid compound, and stirring.

  As a stirrer used for stirring, a stirrer equipped with a stirring blade, a disintegrator, a beater, a low pressure homogenizer, a high pressure homogenizer, a grinder, a cutter mill, a ball mill, a jet mill, a roll mill, a short shaft kneader, a twin screw kneader Short screw extruder, twin screw extruder, ultrasonic stirrer, household use juicer mixer and the like. In addition, it is possible to sufficiently stir each component even with a slight mechanical force such as a magnetic stirrer, propeller mixer, manual stirring by means of a medicine bowl or shaking. The conditions of temperature and pressure at the time of stirring can also be appropriately set according to the amount and type of each component.

<Fine cellulose fiber composite dispersion of an embodiment further containing a resin>
The fine cellulose fiber composite dispersion of the present invention may further contain a resin. Since a molded product can be produced by a known molding method using the dispersion of the present embodiment containing a resin (also referred to as a "resin-containing composition liquid"), a finely divided cellulose fiber composite dispersion of a resin-containing embodiment Is one of the preferred embodiments of the present invention.

〔resin〕
Although usable resins are not particularly limited, for example, thermoplastic resins, curable resins, cellulose resins, and rubber resins can be used. The thermoplastic resin, the curable resin, the cellulose-based resin and the rubber-based resin may be used alone as a resin or in combination of two or more.

(Thermoplastic resin)
As thermoplastic resin, saturated polyester resin such as polylactic acid resin; olefin resin such as polyethylene resin, polypropylene resin; vinyl chloride resin, vinylidene chloride resin, styrene resin, vinyl ether resin, polyvinyl alcohol resin, polyvinyl acetal resin, polyvinyl acetate Vinyl resins such as resins; (meth) acrylic resins; polyamide resins; polycarbonate resins; polysulfone resins; polyurethane resins and the like. These thermoplastic resins may be used alone or in combination of two or more. Among these, an olefin resin, a polyurethane resin, a polycarbonate resin, a (meth) acrylic resin, and a vinyl resin are preferable because a dispersion having excellent dispersibility is obtained. In the present specification, (meth) acrylic resin means a concept including methacrylic resin and acrylic resin.

  As the (meth) acrylic resin, one containing 50% by weight or more of methyl (meth) acrylate as a monomer unit based on the total of the monomer units of all the polymers constituting the resin is preferable, Methacrylic resin is more preferable.

  The methacrylic resin can be produced by copolymerizing methyl methacrylate and other monomers copolymerizable therewith. The polymerization method is not particularly limited, and examples thereof include bulk polymerization method, solution polymerization method, suspension polymerization method, cast polymerization method (for example, cell cast polymerization method) and the like.

(Curable resin)
As the curable resin, a photocurable resin and / or a thermosetting resin is preferable.
A polymerization reaction advances a photocurable resin by using the photoinitiator which generate | occur | produces a radical and a cation by active energy ray irradiation, such as an ultraviolet-ray and an electron beam.

  Examples of the photopolymerization initiator include acetophenones, benzophenones, ketals, anthraquinones, thioxanthones, azo compounds, peroxides, 2,3-dialkyldione compounds, disulfide compounds, thiuram compounds, fluoroamines Compounds etc. may be mentioned. More specifically, the compound described in paragraph 0113 of JP-A No. 2018-024967 can be mentioned.

  For example, monomers (monofunctional monomers, polyfunctional monomers), oligomers having a reactive unsaturated group, resins and the like can be polymerized with a photopolymerization initiator.

  Examples of monofunctional monomers include (meth) acrylic monomers such as (meth) acrylic acid ester, vinyl monomers such as vinylpyrrolidone, isobornyl (meth) acrylate, adamantyl (meth) acrylate and the like. The (meth) acrylate etc. which have a bridged cyclic hydrocarbon group are mentioned. The polyfunctional monomers include polyfunctional monomers having a polymerizable group of about 2 to 8, and examples of the bifunctional monomers include ethylene glycol di (meth) acrylate, propylene glycol di (meth) And di) (meth) acrylates having a crosslinked cyclic hydrocarbon group such as acrylate). As a 3-8 functional monomer, glycerin tri (meth) acrylate etc. are mentioned, for example.

  As an oligomer or resin having a reactive unsaturated group, (meth) acrylate of bisphenol A-alkylene oxide adduct, epoxy (meth) acrylate (bisphenol A epoxy (meth) acrylate, novolac epoxy (meth) acrylate, etc.) , Polyester (meth) acrylate (eg, aliphatic polyester type (meth) acrylate, aromatic polyester type (meth) acrylate, etc.), urethane (meth) acrylate (polyester type urethane (meth) acrylate, polyether type urethane (meth) Acrylate etc.), silicone (meth) acrylate etc. can be illustrated. These oligomers or resins may be used together with the monomers.

  The photocurable resin is preferable from the viewpoint of obtaining a dispersion having a small amount of aggregates and excellent in transparency and a resin molded product.

  As a thermosetting resin, an epoxy resin, a phenol resin, a phenoxy resin, a urea resin, a melamine resin, unsaturated polyester resin, a diallyl phthalate resin, a polyurethane resin, a silicon resin, a polyimide resin etc. are mentioned, for example. A thermosetting resin can be used individually by 1 type or in combination of 2 or more types. Among these, an epoxy resin, a phenoxy resin, a phenol resin, a urea resin, a melamine resin, an unsaturated polyester resin and a polyurethane resin are preferable because a dispersion having excellent dispersibility is obtained, and an epoxy resin, a phenol resin and a phenoxy resin And polyurethane resins are more preferred.

  When using the said resin component, it is preferable to use a hardening | curing agent. By blending the curing agent, the resin molded product obtained from the dispersion liquid containing the resin can be strongly shaped, and the mechanical strength can be improved. The compounding amount of the curing agent may be appropriately set according to the type of resin and / or the type of curing agent to be used.

(Cellulose resin)
Cellulose resins include organic acid esters such as cellulose acetate (cellulose acetate) and cellulose mixed acylate such as cellulose acetate propionate; inorganic acid esters such as cellulose nitrate and cellulose phosphate; organic acid inorganic acids such as cellulose acetate acetate Mixed acid esters; and cellulose ether esters such as acetylated hydroxypropyl cellulose. The cellulose acetate includes cellulose triacetate (acetyl substitution degree 2.6 to 3), cellulose diacetate (acetyl substitution degree 2 or more and less than 2.6), and cellulose monoacetate. The cellulose-based resin may be used alone or in combination of two or more.

(Rubber-based resin)
In the present invention, a rubber-based resin can be used as the resin. In order to increase the strength, rubber-based resins are generally used as a reinforcing material, such as inorganic filler compounds such as carbon black and silica, but their reinforcing effect is considered to have a limit. However, since it is excellent in the dispersibility in the dispersion liquid obtained by mix | blending rubber-type resin with the dispersion liquid of this invention, the dispersion liquid and molded object (rubber) which are excellent in mechanical strength and heat resistance are provided. Will be possible.

As the rubber-based resin, diene-based rubber and non-diene-based rubber are preferable.
Examples of the diene rubber include natural rubber, polyisoprene rubber, polybutadiene rubber, styrene-butadiene copolymer rubber, butyl rubber, butadiene-acrylonitrile copolymer rubber, chloroprene rubber, modified natural rubber and the like. Examples of the modified natural rubber include epoxidized natural rubber and hydrogenated natural rubber. Examples of non-diene rubber include butyl rubber, ethylene-propylene rubber, ethylene-propylene-diene rubber, urethane rubber, silicone rubber, fluororubber, acrylic rubber, polysulfide rubber, epichlorohydrin rubber and the like. These can be used alone or in combination of two or more.

  Overall, as the resin contained in the fine cellulose fiber composite dispersion, an olefin resin, a polyurethane resin, a polycarbonate resin, a (meth) acrylic resin, an epoxy resin, a phenol resin, a phenoxy resin, a vinyl resin and a rubber resin One or more selected from the group consisting of

  The amount of the resin in the dispersion of the present embodiment can not be determined generally depending on the desired physical properties of the dispersion and the molding method, but it is obtained based on 100 parts by mass of the organic liquid compound in terms of the compounding amount. From the viewpoint of the mechanical strength of the molded product to be made, it is preferably 1 part by mass or more, more preferably 5 parts by mass or more, still more preferably 10 parts by mass or more. Is 1000 parts by mass or less, more preferably 500 parts by mass or less, and still more preferably 300 parts by mass or less.

[Other ingredients]
The fine cellulose fiber composite dispersion may contain components other than the fine cellulose fiber composite, the dispersant, and the organic liquid compound. As such “other components”, for example, those easily soluble in organic liquid compounds such as glycerin, glycerin derivatives, dimethyl sulfoxide (DMSO), ethylene glycol, propylene glycol, polyethylene glycol, dimethylformamide and the like can be mentioned.

  In addition to the above components, plasticizers, crystal nucleating agents, fillers (inorganic fillers, organic fillers), hydrolysis inhibitors, flame retardants, antioxidants, hydrocarbon waxes, etc. Lubricants which are anionic type surfactants, UV absorbers, antistatic agents, antifogging agents, light stabilizers, pigments, antifungal agents, antibacterial agents, foaming agents, surfactants; polysaccharides such as starches, alginic acid; Natural proteins such as gelatin, glue, casein, etc .; Inorganic compounds such as tannins, zeolites, ceramics, metal powders, etc .; perfumes; flow control agents; leveling agents; conductive agents; ultraviolet light dispersants; It can contain in the range which does not impair an effect. Similarly, it is also possible to add other polymer materials and other resin compositions as long as the effects of the present invention are not impaired.

  The plasticizer is not particularly limited, and examples thereof include polybasic carboxylic acid esters such as phthalic acid esters and succinic acid esters which are conventional plasticizers, adipic acid esters, and fatty acid esters of aliphatic polyols such as glycerin. Specifically, the plasticizers described in JP-A-2008-174718 and JP-A-2008-115372 are exemplified.

  In addition, when the dispersion liquid of the present embodiment contains a rubber-based resin, as components other than the above, carbon black, silica, etc. which are usually used in the rubber industry as desired within a range not impairing the object of the present invention. Fillers, various chemicals such as vulcanizing agents, vulcanization accelerators, anti-aging agents, anti-scorking agents, zinc flower, stearic acid, processing oils, tires for plant oils and fats, plasticizers and other general rubber The various additives formulated in can be formulated in conventional and conventional amounts.

  The content of the “other components” in the dispersion liquid of the present invention is not particularly limited, but is preferably 0.1% by mass or more, more preferably 0.5% by mass or more from the viewpoint of dispersibility. It is not more than mass%, more preferably not more than 10 mass%.

[Method of Preparing Dispersion of this Embodiment]
The dispersion of this embodiment is prepared by dispersing the above-mentioned resin, fine cellulose fiber composite, dispersing agent, and organic liquid compound together with other components as necessary, using a high-pressure homogenizer. be able to. Alternatively, these raw materials are stirred with a Henschel mixer, a rotation-revolution type stirrer or the like, or melt-kneaded using a known kneader such as a closed kneader, a single or twin screw extruder, or an open roll kneader. It can also be prepared.

<Resin molding>
The resin molded product can be prepared by appropriately using a known molding method such as extrusion molding, injection molding, press molding, cast molding, or solvent casting method using the dispersion liquid of the above aspect containing a resin. Since the dispersion of the present invention is excellent in the dispersibility of the fine cellulose fiber composite, the mechanical strength of various resin products which are molded articles is improved as compared with the conventional product. Therefore, a resin molding can be used suitably for various uses.

  The use in which the dispersion or resin molded product of the above aspect containing a resin can be used is not particularly limited. For example, transparent resin materials, three-dimensional shaping materials, cushioning materials, repair materials, adhesives, adhesives, sealing materials, heat insulating materials, It can be used for sound absorbing materials, artificial leather materials, paints, electronic materials, packaging materials, tires, automobile parts, and fiber composite materials. Among them, transparent resin materials, adhesives, adhesives, artificial leather materials, paints, electronic materials, fiber composite materials are particularly preferable from the viewpoint of obtaining molded articles having excellent transparency, and from the viewpoint of strength development Three-dimensional modeling materials, cushioning materials, repair materials, sealing materials, heat insulating materials, sound absorbing materials, tires, automotive parts applications are preferred.

  EXAMPLES Hereinafter, the present invention will be specifically described by showing Examples and Comparative Examples, but the present invention is not limited to the following Examples.

Crystallinity of Cellulose
The crystallinity of cellulose in the fine cellulose fiber and the fine cellulose fiber composite is a cellulose type I crystallinity calculated by the Segal method from the diffraction intensity value by the X-ray diffraction method, and is defined by the following formula (A) .
Cellulose type I crystallinity (%) = [(I22.6−I18.5) /I22.6] × 100 (A)
[Wherein, I22.6 is the diffraction intensity of the grating surface (002 plane) (diffraction angle 2θ = 22.6 °) in X-ray diffraction, I18.5 is the amorphous part (diffraction angle 2θ = 18.5 °) Shows the diffraction intensity of ]

[Average fiber diameter and average fiber length of cellulose fiber, anion-modified cellulose fiber and anion-modified cellulose fiber composite]
Ion-exchanged water is added to the cellulose fiber to be measured to prepare a dispersion having a content of 0.01% by mass. Using a wet dispersion type image analysis particle size distribution analyzer (trade name: IF-3200, manufactured by Jusco International Co., Ltd.), the front lens: 2 ×, telecentric zoom lens: 1 ×, image resolution: 0.835 μm / pixel , Syringe inner diameter: 6515 μm, spacer thickness: 500 μm, image recognition mode: ghost, threshold value: 8, analysis sample amount: 1 mL, sampling: measured under the conditions of 15%. One hundred or more cellulose fibers are measured, and their average ISO fiber diameter is calculated as an average fiber diameter, and an average ISO fiber length is calculated as an average fiber length.

[Average fiber diameter of fine cellulose fiber and fine cellulose fiber composite]
Water or ethanol is added to a fine cellulose fiber or fine cellulose fiber composite to prepare a dispersion having a content of 0.0001% by mass, and the dispersion is dropped onto mica (mica) and dried. As an observation sample, an atomic force microscope (AFM, Nanoscope III Tapping mode AFM, manufactured by Digital instrument, using a point probe (NCH) manufactured by Nanosensors Co., Ltd.), fibers of cellulose fibers in the observation sample Measure the height. At that time, in a microscope image in which the cellulose fiber can be confirmed, 100 or more fine cellulose fibers or a fine cellulose fiber complex are extracted, and the average fiber diameter is calculated from the height of the fibers. The average fiber length is calculated from the distance in the fiber direction. The average aspect ratio is calculated from the average fiber length / average fiber diameter, and the standard deviation is also calculated.

[Anionic group content of anion-modified cellulose fiber, fine cellulose fiber and fine cellulose fiber composite]
A dry mass of 0.5 g of a cellulose fiber or complex to be measured is placed in a 100 mL beaker, ion-exchanged water is added to make a total of 55 mL, and 5 mL of a 0.01 M aqueous sodium chloride solution is added thereto to prepare a dispersion. The dispersion is stirred until the cellulose fiber or complex to be measured is sufficiently dispersed. The pH is adjusted to 2.5 to 3 by adding 0.1 M hydrochloric acid to this dispersion, and a 0.05 M aqueous solution of sodium hydroxide is added using an automatic titrator (trade name "AUT-501" manufactured by Toa DK Co., Ltd.). The dispersion is dropped on the condition of a waiting time of 60 seconds, and the conductivity and pH value are measured every minute. Measurement is continued until the pH is around 11, and a conductivity curve is obtained. The sodium hydroxide titer is determined from this conductivity curve, and the anionic group content of the cellulose fiber or complex to be measured is calculated by the following equation.
Anionic group content (mmol / g) = sodium hydroxide titer × sodium hydroxide aqueous solution concentration (0.05 M) / mass of cellulose fiber or complex to be measured (0.5 g)

[Average binding amount and introduction ratio of amine of anion-modified cellulose fiber composite and fine cellulose fiber composite (ion binding)]
The bound amount of amine is determined by the following IR measurement method, and the average bound amount and the introduction rate are calculated by the following formula. Specifically for IR measurement, the dried fine cellulose fiber or fine cellulose fiber complex is subjected to an ATR method using an infrared absorption spectrometer (IR) (trade name: Nicolet 6700 manufactured by Thermo Fisher Scientific Co., Ltd.). The average binding amount and introduction rate of amine by ion binding are calculated by the following equation. The following shows the case where the anionic group is a carboxy group. The following “peak intensity at 1720 cm ⁻¹ ” is a peak intensity derived from a carbonyl group. In the case of an anionic group other than a carboxy group, the value of peak intensity may be appropriately changed to calculate the average bonding amount and the introduction ratio of amines.

Amine binding amount (mmol / g) = [carboxy group content of fine cellulose fiber (mmol / g)] × [(peak strength of 1720 cm ⁻¹ of fine cellulose fiber—1720 cm of fine cellulose fiber composite after amine bonding Peak intensity of ^-1 ) / peak intensity of 1720 cm ^-1 of fine cellulose fiber]

  Amine introduction rate (%) = 100 × (amine binding amount (mmol / g)) / (carboxy group content in fine cellulose fiber before introduction (mmol / g))

[Viscosity of dispersion]
The viscosity of the fine cellulose fiber composite dispersion is measured with a rheometer (MCR 502, manufactured by Anton Paar) using a cone plate (CP 75-1) at 25 ° C. and a shear rate of 1 rpm.

[Preparation of Fine Cellulose Fiber]
Preparation Example 1
Softwood bleached kraft pulp (Fletcher Challenge Canada, trade name "Machenzie", CSF 650 ml) was used as a natural cellulose fiber. As TEMPO, a commercial item (manufactured by ALDRICH, Free radical, 98% by mass) was used. Sodium hypochlorite and sodium bromide were commercially available products.

  First, 100 g of softwood bleached kraft pulp fiber is sufficiently stirred with 9,900 g of ion-exchanged water, and with respect to 100 g of the pulp mass, 1.25 g of TEMPO, 12.5 g of sodium bromide, 28.4 g of sodium hypochlorite Were added in this order. Using a pH stat titration with an automatic titrator AUT-701 (manufactured by Toa DK Co., Ltd.), the pH was maintained at 10.5 by dropwise addition of a 0.5 M aqueous solution of sodium hydroxide under sufficient stirring. The reaction was carried out for 120 minutes (20 ° C.), after which the dropwise addition of the aqueous sodium hydroxide solution was stopped to obtain an oxidized pulp. Using deionized water, the obtained oxidized pulp is thoroughly washed to a level of 200 μs / cm or less in conductivity measurement of the filtrate by a compact conductivity meter (LAQUAtwin EC-33B, manufactured by Horiba, Ltd.), and then Dehydration was performed. After that, 3.9 g of oxidized pulp and 296.1 g of ion-exchanged water are finely treated twice at 245 MPa using a high-pressure homogenizer (Starburst Lab HJP-2505 manufactured by Sugino Machine Co., Ltd.) to obtain a fine cellulose fiber The dispersion liquid (solid content: 1.3% by mass) was obtained. The average fiber diameter of this fine cellulose fiber was 3.3 nm, and the carboxy group content was 1.8 mmol / g.

Preparation Example 2
A dispersion of 4,088.75 g (solid content: 1.3% by mass) of the fine cellulose fibers obtained in Preparation Example 1 and 4,085 g of ion-exchanged water are put in a beaker to form a 0.5% by mass aqueous solution. The mixture was stirred for 30 minutes at room temperature (25 ° C.) with a mechanical stirrer. Subsequently, 245 g of a 1 M aqueous hydrochloric acid solution was charged in a beaker, and stirred at room temperature for 1 hour for reaction.
After completion of the reaction, the resulting cake was thoroughly washed with ion-exchanged water as described above to remove hydrochloric acid and salts. After solvent substitution with acetone, solvent substitution is carried out with methyl ethyl ketone (MEK) to obtain a dispersion (solid content: 3.2 mass%) of MEK-containing acid-type fine cellulose fibers in a state in which the fine cellulose fibers are swollen. The average fiber diameter of this fine cellulose fiber was 3.3 nm, and the carboxy group content was 1.8 mmol / g.

[Preparation of EO / PO copolymerized amine]
Preparation Example 3
132 g (1 mol) of propylene glycol tertiary butyl ether was charged in a 1 L autoclave, heated to 75 ° C., 1.2 g of potassium hydroxide in the form of flakes was added, and stirred until it was dissolved. Next, ethylene oxide (EO) and propylene oxide (PO) in the amounts shown in Table 1 were supplied to the autoclave and reacted at 110 ° C. and 0.34 MPa, after which Magnesol 30/40 (magnesium silicate, Dallas Group Inc.) 7.14 g was added and neutralized at 95 ° C. To the obtained product, 0.16 g of di-tert-butyl-p-cresol was added, mixed, and filtered to obtain a polyether which is an EO / PO copolymer.

On the other hand, in a 1.250 mL tubular reaction vessel filled with a catalyst of nickel oxide / copper oxide / chromium oxide (molar ratio: 75/23/2) (Wako Pure Chemical Industries, Ltd.), the polyether obtained above (8 .4 mL / min), ammonia (12.6 mL / min) and hydrogen (0.8 mL / min) were respectively supplied. The temperature of the vessel was maintained at 190 ° C. and the pressure was maintained at 14 MPa. The crude effluent from the vessel was evaporated under reduced pressure at 70 ° C. and 3.5 mmHg for 30 minutes. 200 g of the resulting aminated polyether and 93.6 g of a 15% aqueous hydrochloric acid solution were charged in a flask, and the mixture was heated at 100 ° C. for 3.75 hours to cleave tertiary butyl ether with hydrochloric acid. The product was then neutralized with 144 g of a 15% aqueous potassium hydroxide solution. Next, the neutralized product was evaporated under reduced pressure at 112 ° C. for 1 hour and filtered to obtain a monoamine having an EO / PO copolymer represented by the formula (i). In the monoamine thus obtained, the EO / PO copolymer and the amine are directly bonded, and R ₁ in the formula (i) is a hydrogen atom.

The molecular weight of the EO / PO copolymer part is, for example, in the case of the amine of Table 1,
1,409 [EO molecular weight (44.03) × EO addition mole number (32)] + 522 [PO molecular weight (58.04) × PO addition mole number (9)] + 58.04 [PO partial molecular weight in starting material ( Propylene glycol)] = 1, 989
Was rounded off and calculated to be 2,000.

[Production of fine cellulose fiber composite]
Production Example 1
In a beaker equipped with a magnetic stirrer and a stirrer, 50 g (solid content: 3.2% by mass) of the dispersion of the fine cellulose fiber obtained in Preparation Example 2 was charged. Subsequently, the EOPO amine obtained in Preparation Example 3 was charged in this beaker in an amount corresponding to 0.3 mol of amino group to 1 mol of carboxy group of the fine cellulose fiber, and was dissolved in 150 g of DMF. Then, it was reacted by stirring at room temperature (25 ° C.) for 14 hours. After completion of the reaction, the mixture is filtered, and the cake is washed sufficiently with MEK 1 L or more to remove free amines, thereby removing EIPO amine from the fine cellulose fibers via ionic bonds (fine content: 3.%). 5 mass%) was obtained. The average fiber diameter of this fine cellulose fiber composite was 3.3 nm, and the carboxy group content was 1.8 mmol / g.

[Production of Dispersion]
Examples 1 to 2 and Comparative Example 1
In the finely divided cellulose fiber composite produced in Production Example 1, a blend (homogenol L-95, manufactured by Kao Corporation) and liquid paraffin (SP value: 7.9, manufactured by Wako Pure Chemical Industries, Ltd.) are shown in Table 2 The mixture was added so that the amount was adjusted and stirred for 2 minutes with an ultrasonic homogenizer (US-300E, manufactured by Nippon Seiki Seisakusho Co., Ltd.), then 5 passes at 150 MPa with a high pressure homogenizer Mixed processing. The obtained mixture was poured into a glass petri dish and vacuum dried at 40 ° C. for 2 days to remove MEK, thereby producing a dispersion which is a mixture of a dispersant, liquid paraffin and a fine cellulose fiber composite.

Comparative example 2
In the same manner as in Example 1 except that the fine cellulose fiber composite was changed to the fine cellulose fiber produced in Preparation Example 1, a dispersion which is a mixture of a dispersant, liquid paraffin and fine cellulose fiber was produced. As a result of measuring the viscosity at 25 ° C. of the obtained dispersion liquid, the dispersion liquid was in a separated state, and viscosity measurement was impossible.

Test Example 1 (Dispersibility)
The appearance of each of the mixtures produced in Examples and Comparative Examples was visually observed to confirm whether they were uniformly dispersed and evaluated according to the following criteria.
○: The mixture was uniformly dispersed.
X: The mixture was separated and not uniformly dispersed.

  From the above results, it was found that the dispersibility is improved by applying the dispersing agent even in the composition (Comparative Example 1) in which the dispersibility of the fine cellulose fiber composite is poor (Examples 1, 2) ). On the other hand, when the fine cellulose fiber which the amine did not couple | bond with the carboxy group was used instead of the fine cellulose fiber composite, it has confirmed that the dispersibility was bad (comparative example 2).

  The fine cellulose fiber composite dispersion of the present invention comprises a transparent resin material, a three-dimensional shaping material, a cushioning material, a repair material, an adhesive, an adhesive, a sealing material, a heat insulating material, a sound absorbing material, an artificial leather material, a paint, an electronic material It can be used as a mechanical strength improver for various resin products such as packaging materials, tires, automobile parts, and fiber composite materials.

Claims (6)

  A fine cellulose fiber composite dispersion comprising a fine cellulose fiber composite in which an amine is bonded via an ionic bond to an anionic group of an anionically modified cellulose fiber containing an anionic group, a dispersant, and an organic liquid compound .   The fine cellulose fiber composite dispersion according to claim 1, wherein the dispersant is an alkyl imidazoline compound.   The finely divided cellulose fiber composite dispersion according to claim 1 or 2, wherein the organic liquid compound comprises one or more oils selected from the group consisting of vegetable oil, animal oil, synthetic oil and liquid paraffin. .   The fine cellulose fiber composite dispersion according to any one of claims 1 to 3, further comprising a resin.   The resin is one or more selected from the group consisting of an olefin resin, a polyurethane resin, a polycarbonate resin, a (meth) acrylic resin, an epoxy resin, a phenol resin, a phenoxy resin, a vinyl resin and a rubber resin. 4. The fine cellulose fiber composite dispersion as described in 4.   The resin molded object formed by shape | molding the fine cellulose fiber composite dispersion liquid of Claim 4 or 5.