Thiol compound-containing composition

Abstract

To provide a thiol compound-containing composition that contains cellulose fibers with excellent dispersibility and transparency.SOLUTION: A thiol compound-containing composition contains a thiol compound and modified cellulose fibers. The modified cellulose fibers have cellulose I-type crystal and are one or more selected from cellulose fibers (A) and / or cellulose fibers (B). The modified cellulose fibers (A): modified cellulose fibers with modifying groups bound to ionic groups of cellulose fibers. Modified cellulose fibers (B): modified cellulose fibers with modifying groups bound to hydroxy groups of cellulose fibers.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a thiol compound-containing composition and a method for producing the same.

Background Art

[0002] Conventionally, plastic materials derived from petroleum, which are finite resources, have been widely used. In recent years, technologies with less environmental impact have come into the spotlight. Under such a technical background, cellulose fibers, which are biomass abundantly present in nature, and in particular, materials using microcrystalline cellulose fibers have attracted attention because various mechanical properties are significantly improved.

[0003] Patent Document 1 describes a composition comprising cellulose nanofibers, a resin binder and / or an organic compound having a reactive group, and discloses that the resin binder is at least one of a hydroxyl group (-OH), a carboxyl group (-COOH), an amino group (-NH2), a thiol group (-SH) and / or derivatives thereof, and / or an organic compound having a double bond.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in Patent Document 1, it cannot be said that the dispersibility of cellulose fibers in the resin binder is sufficient. By using a thiol compound-containing composition containing cellulose fibers with high dispersibility, it is considered that the resulting resin composition has excellent transparency and is also connected to the improvement of strength and impact resistance.

[0006] The present invention relates to a thiol compound-containing composition excellent in the dispersibility and transparency of cellulose fibers.

Means for Solving the Problems

[0007] The present invention relates to the following [1] to [3]. 〔1〕 A thiol compound-containing composition containing a thiol compound and a modified cellulose fiber, wherein the modified cellulose fiber has a cellulose I-type crystal and is one or more selected from the group consisting of the following cellulose fibers (A) and cellulose fibers (B). Modified cellulose fiber (A): A modified cellulose fiber in which a modifying group is bonded to an ionic group of a cellulose fiber containing an ionic group Modified cellulose fiber (B): A modified cellulose fiber in which a modifying group is bonded to a hydroxy group of a cellulose fiber 〔2〕 A method for producing the thiol compound-containing composition according to [1] above, which includes a step of refining a modified cellulose fiber having an average fiber length exceeding 500 nm in a thiol compound, and the modified cellulose fiber subjected to the refining step is one or more selected from the group consisting of the following modified cellulose fibers (A) and modified cellulose fibers (B). Modified cellulose fiber (A): A modified cellulose fiber in which a modifying group is bonded to an ionic group of a cellulose fiber containing an ionic group Modified cellulose fiber (B): A modified cellulose fiber in which a modifying group is bonded to a hydroxy group of a cellulose fiber 〔3〕 A polymerization product of the thiol compound-containing composition according to [1] above.

Effects of the Invention

[0008] According to the present invention, it is possible to provide a thiol compound-containing composition excellent in the dispersibility and transparency of cellulose fibers.

Modes for Carrying Out the Invention

[0009] As a result of intensive studies by the inventors of the present invention on the above problems, it has been newly found that a thiol compound-containing composition excellent in the dispersibility of modified cellulose fibers can be obtained by blending specific modified cellulose fibers with a thiol compound. Although such a mechanism is not clear, it is presumed that this is because specific modified cellulose has high dispersibility with respect to the thiol compound.

[0010] 〔Thiol compound-containing composition〕 The thiol compound-containing composition of the present invention contains a thiol compound and modified cellulose fibers.

[0011] 〔Thiol compound〕 The thiol compound is not particularly limited as long as it contains a thiol group (-SH). From the perspective of dispersibility, a polythiol compound having two or more thiol groups is preferred. The polythiol compound may be linear, branched, or cyclic, and as long as it has two or more thiol groups (-SH), it may also have other functional groups, such as functional groups having active hydrogen such as an amine group or a hydroxyl group. Examples of such polyfunctional polythiol compounds include 1,2-propanedithiol, 1,3-propanedithiol, 1,2,3-propanetrithiol, 1,2,3-tris(mercaptomethylthio)propane, 1,2,3-tris(2-mercaptoethylthio)propane, 1,2,3-tris(3-mercaptopropylthio)propane, 2,5-bis(mercaptomethyl)-1,4-dithiane, pentaerythritol tetrakis(mercaptoacetate), pentaerythritol tetrakis(mercaptopropionate), trimethylolpropane tris(mercaptoacetate), trimethylolpropane tris(mercaptopropionate), 1,2,3-trimercaptopropane, 2,3-dimercapto-1-propanol, bis(mercaptoethyl) sulfide, bis(mercaptoethyl) disulfide, 1,2-bis(mercaptoethylthio)-3-mercaptopropane, 2,5-dimercaptomethyl-1,4-dithiane, ethylene glycol bis(3-mercaptopropionate), 4,6-bis(mercaptomethylthio)-1,3-dithiane, and bis(2-mercaptoethyl) sulfide, 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane, 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, and 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, etc. These may be used alone or in combination of two or more. Furthermore, examples include polyhydric alcohol esters of mercaptocarboxylic acids, esters of monomeric mercaptans and monohydric alcohols containing polycarboxylic acids, compounds having a mercaptan group at the ends of polypropylene glycol or polyethylene glycol chains, other ester-containing polymercaptans described in U.S. Patent No. 4,126,505, propoxylated ether polythiols described in U.S. Patent No. 4,092,293, polymercaptan-containing resins having a molecular weight of 750 to 7000 described in U.S. Patent No. 3,258,495, dimercaptopolysulfide polymers described in U.S. Patent No. 2,919,255, thiolated oligomer triglycerides, and the like. Among these, polyhydric alcohol esters of mercaptocarboxylic acids are preferred. Examples of polyhydric alcohol esters of mercaptocarboxylic acids preferably include trimethylolpropane trimercaptopropionate, trimethylolpropane trithiogluconate, pentaerythritol tetramercaptopropionate, pentaerythritol tetrathiogluconate, trimethylolethane trimercaptopropionate, and the like. The polythiol compound can be reacted with an isocyanate to produce a thiourethane resin.

[0012] From the perspective of dispersibility, the average molecular weight of the thiol compound is preferably 100 or more, more preferably 150 or more, and still more preferably 200 or more. Also, from the perspective of dispersibility, it is preferably 5000 or less, more preferably 3000 or less, and still more preferably 1000 or less. In this specification, the average molecular weight of the thiol compound is the mass average molecular weight.

[0013] 〔Modified cellulose fiber〕 The modified cellulose fiber contained in the thiol compound-containing composition of the present invention is one or more selected from the group consisting of the following modified cellulose fibers (A) and modified cellulose fibers (B), and those containing one or more modifying groups selected from the group consisting of (a) a hydrocarbon group and (b) a polymer group are preferred. Modified cellulose fiber (A): A modified cellulose fiber obtained by bonding a modifying group to an ionic group of a cellulose fiber containing an ionic group Modified cellulose fiber (B): A modified cellulose fiber obtained by bonding a modifying group to a hydroxy group of a cellulose fiber

[0014] As the cellulose fiber which is the raw material of the modified cellulose fiber, from the viewpoint of reducing environmental load, it is preferable to use natural cellulose fiber. Examples of the natural cellulose fiber include wood pulp such as softwood pulp and hardwood pulp; cotton-based pulp such as cotton linter and cotton lint; non-wood pulp such as wheat straw pulp and bagasse pulp; bacterial cellulose and the like. These can be used alone or in combination of two or more kinds.

[0015] The average fiber diameter and average fiber length of the raw material cellulose fiber are not particularly limited. As the average fiber diameter, for example, from the viewpoints of easy availability and cost reduction, it is preferably 1 μm or more, and from the same viewpoints, it is preferably 100 μm or less. As the average fiber length, for example, from the viewpoints of easy availability and cost reduction, it is preferably 1000 μm or more, and from the same viewpoints, it is preferably 10000 μm or less. The average fiber diameter and average fiber length of the raw material cellulose fiber can be measured by the method described in the examples below.

[0016] <Modified cellulose fiber (A)> The modified cellulose fiber (A) in the present invention is a modified cellulose fiber obtained by bonding a modifying group to an ionic group of a cellulose fiber containing an ionic group.

[0017] (Ionic group) The cellulose fiber containing an ionic group is a cellulose fiber modified so as to contain an ionic group in the cellulose fiber.

[0018] Examples of the ionic group include an anionic group and a cationic group. In this specification, the cellulose fiber having an anionic group is also referred to as "anion-modified cellulose fiber". Examples of the anionic group include a carboxy group, a sulfonic acid group, and a phosphoric acid group, etc., and examples of the cationic group include a group having an onium such as ammonium, phosphonium, and sulfonium in the group. From the viewpoint of the introduction efficiency into the modified cellulose fiber (A), the anionic group is preferable as the ionic group, and the carboxy group is more preferable as the anionic group. The anion-modified cellulose fiber is preferably an oxidized cellulose fiber or a carboxymethylated cellulose fiber from the viewpoint of introducing a modifying group, and more preferably a cellulose fiber in which the C6 position of the cellulose structural unit is a carboxy group.

[0019] When the ionic group is an anionic group, the ion (counter ion) that pairs with the anionic group is one or more selected from the group consisting of a metal ion and a proton. The metal ion is preferably a monovalent cation, and examples thereof include a lithium ion, a sodium ion, and a potassium ion, etc. From the viewpoint of the reaction efficiency with the modified cellulose fiber, a proton is preferable.

[0020] From the viewpoints of stable fibrillation and introduction of a modifying group, the content of the ionic group in the cellulose fiber containing the ionic group is preferably 0.1 mmol / g or more, more preferably 0.4 mmol / g or more, and still more preferably 0.6 mmol / g or more. From the same viewpoints, the upper limit is preferably 3.0 mmol / g or less, more preferably 2.5 mmol / g or less, and still more preferably 2.0 mmol / g or less. The content of the anionic group when the ionic group is an anionic group can be measured by the method described in the examples below.

[0021] (Modifying group) In the modified cellulose fiber (A), a modifying group is bonded to the ionic group of the cellulose fiber containing an ionic group. Examples of the bonding mode here include ionic bonds and covalent bonds (for example, amide bonds, ester bonds, urethane bonds, etc.).

[0022] The modified cellulose fiber (A) preferably contains at least one modifying group selected from the group consisting of (a) a hydrocarbon group and (b) a polymer group. These groups may be introduced into the modified cellulose fiber (A) alone or in combination of two or more. From the viewpoint of dispersibility, it is preferable that (a) a hydrocarbon group and (b) a polymer group are introduced into the modified cellulose fiber (A).

[0023] From the viewpoint of improving dispersibility and transparency, the number of carbon atoms of the hydrocarbon group as the modifying group is preferably 1 or more, more preferably 2 or more, still more preferably 3 or more, and from the same viewpoint, preferably 30 or less, more preferably 25 or less, still more preferably 24 or less, still more preferably 20 or less, still more preferably 18 or less. The number of carbon atoms of the hydrocarbon group means the number of carbon atoms in one modifying group unless otherwise specified.

[0024] Specific examples of the chain saturated hydrocarbon group include, for example, methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, tert-butyl group, isobutyl group, pentyl group, tert-pentyl group, isopentyl group, hexyl group, isohexyl group, heptyl group, octyl group, 2-ethylhexyl group, nonyl group, decyl group, dodecyl group, tridecyl group, tetradecyl group, octadecyl group, docosyl group, octacosanyl group, etc.

[0025] Specific examples of the chain unsaturated hydrocarbon group include, for example, ethylene group, propylene group, butene group, isobutene group, isoprene group, pentene group, hexene group, heptene group, octene group, nonene group, decene group, dodecene group, tridecene group, tetradecene group, octadecene group.

[0026] Specific examples of the cyclic saturated hydrocarbon group include, for example, cyclopropane group, cyclobutyl group, cyclopentane group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclononyl group, cyclodecyl group, cyclododecyl group, cyclotridecyl group, cyclotetradecyl group, cyclooctadecyl group, and the like.

[0027] The aromatic hydrocarbon group is selected from the group consisting of, for example, an aryl group and an aralkyl group. The aryl group and the aralkyl group may be either substituted or unsubstituted with the aromatic ring itself.

[0028] Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, a phenanthryl group, a biphenyl group, a diphenyl group, a triphenyl group, a terphenyl group, and groups substituted with the substituents described below.

[0029] Examples of the aralkyl group include a benzyl group, a phenethyl group, a phenylpropyl group, a phenylpentyl group, a phenylhexyl group, a phenylheptyl group, a phenyloctyl group, and groups in which the aromatic group of these groups is further substituted with a substituent. Other examples of the aromatic hydrocarbon group include a diphenylmethyl group, a triphenylmethyl group, and groups in which the aromatic group of these groups is further substituted with a substituent.

[0030] When the modifying group is a hydrocarbon group and the hydrocarbon group has a substituent, examples of the substituent include a linear or branched alkoxy group having 1 to 6 carbon atoms; a linear or branched alkoxycarbonyl group having 1 to 6 carbon atoms in the alkoxy group; a halogen atom such as a bromine atom or an iodine atom; an acyl group having 1 to 6 carbon atoms; an aralkyl group; an aralkyloxy group; an alkylamino group having 1 to 6 carbon atoms; a dialkylamino group having 1 to 6 carbon atoms in the alkyl group, a hydroxy group, an ether, an amide, etc. may also be used. It should be noted that each of the above-mentioned various hydrocarbon groups itself may be bonded as a substituent to another hydrocarbon group.

[0031] A polymer group is a functional group containing a polymer structure. From the perspective of improving dispersibility, the molecular weight of the polymer group is preferably 100 or more, more preferably 200 or more, more preferably 300 or more, still more preferably 400 or more, still more preferably 600 or more, still more preferably 1,000 or more, and still more preferably 1,500 or more. From the same perspective, it is preferably 10,000 or less, more preferably 7,000 or less, still more preferably 5,000 or less, still more preferably 4,000 or less, still more preferably 3,500 or less, and still more preferably 2,500 or less.

[0032] From the perspective of improving dispersibility, the polymer group is preferably a functional group having a repeating structure linked by a structure having an oxygen atom, more preferably a functional group having a repeating structure linked by an oxygen atom, such as a polyoxyalkylene structure (alkylene oxide chain) or a polysiloxane structure (silicone chain), and more preferably a polyoxyalkylene structure, and still more preferably an alkoxypolyoxyalkylene group.

[0033] From the perspective of ensuring the chemical stability of the modified cellulose fiber and the dispersion stability as a filler, the polyoxyalkylene structure is preferably a (co)polymer structure of one or more oxyalkylenes selected from oxyalkylenes having 2 to 8 carbon atoms, more preferably a (co)polymer structure of one or more oxyalkylenes selected from oxyalkylenes having 2 to 4 carbon atoms, still more preferably a (co)polymer structure of one or two oxyalkylenes selected from ethylene oxide (EO) and propylene oxide (PO), and still more preferably a copolymer structure in which ethylene oxide (EO) and propylene oxide (PO) are polymerized randomly or in blocks.

[0034] Examples of the group containing a copolymer structure ((EO / PO) copolymer structure) in which ethylene oxide (EO) and propylene oxide (PO) are polymerized randomly or in blocks include the group represented by the following formula (i’), and it can be introduced using the compound of the following formula (i).

[0035]

Chem.

[0036] [In the formula, R 1 represents a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, or an aminoalkyl group thereof, EO and PO are present randomly or in block form, a is a positive number representing the average number of moles of EO added, and b is a positive number representing the average number of moles of PO added. Here, the "aminoalkyl group thereof" means a group in which one of the hydrogen atoms constituting the linear or branched alkyl group having 1 to 6 carbon atoms is substituted with an amino group. In formula (i), an alkylene group having 1 to 3 carbon atoms may be present between the amino group and EO or PO.]

[0037] R 1 When 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. R 1 may be a hydrogen atom.

[0038] From the viewpoint of improving dispersibility and transparency, a is preferably 1 or more, more preferably 3 or more, still more preferably 6 or more, still more preferably 11 or more, still more preferably 15 or more, still more preferably 20 or more, still more preferably 25 or more, still more preferably 30 or more, still more preferably 40 or more. From the same viewpoint, it is preferably 100 or less, more preferably 90 or less, still more preferably 70 or less, still more preferably 60 or less, still more preferably 50 or less.

[0039] From the viewpoint of improving dispersibility and transparency, b is preferably 1 or more, more preferably 2 or more, still more preferably 3 or more. From the same viewpoint, it is preferably 50 or less, more preferably 40 or less, still more preferably 30 or less, still more preferably 25 or less, still more preferably 20 or less, still more preferably 15 or less, still more preferably 10 or less, still more preferably 5 or less.

[0040] Examples of the alkylene group having 1 to 3 carbon atoms include a methylene group, an ethylene group, and a propylene group.

[0041] (EO / PO) The content rate (mol%) of PO in the copolymerized part can be calculated based on the above a and b, and specifically, it can be obtained from b×100 / (a + b). From the viewpoint of further improving the dispersibility, the content rate of PO is preferably 1 mol% or more, more preferably 3 mol% or more, still more preferably 5 mol% or more. From the same viewpoint, it is preferably 100 mol% or less, more preferably 90 mol% or less, still more preferably 85 mol% or less, still more preferably 75 mol% or less, still more preferably 60 mol% or less, still more preferably 50 mol% or less, still more preferably 40 mol% or less, still more preferably 30 mol% or less, still more preferably 10 mol% or less.

[0042] (EO / PO) The molecular weight of the copolymer structure is preferably 100 or more, more preferably 200 or more, still more preferably 300 or more, still more preferably 400 or more, still more preferably 500 or more, still more preferably 600 or more, still more preferably 1,000 or more, 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 7,000 or less, still more preferably 5,000 or less, still more preferably 4,000 or less, still more preferably 3,500 or less, still more preferably 2,500 or less.

[0043] The amine having an EO / PO copolymer structure represented by formula (i) is a modifying compound for introducing a modifying group represented by formula (i’), and details of the amine are described in, for example, Japanese Patent No. 6105139.

[0044] The amine having the EO / PO copolymer structure (also referred to as "EOPO amine") can preferably use commercially available products. Specific examples include Jeffamine M-2070, Jeffamine M-2005, Jeffamine M-2095, Jeffamine M-1000, Jeffamine M-600, Jeffamine M-3085, Jeffamine ED-600, Jeffamine ED-900, Jeffamine ED-2003, Jeffamine D-230, Jeffamine D-400, Jeffamine D-2000, Jeffamine D-4000, Jeffamine T-3000, Jeffamine T-5000, etc. manufactured by HUNTSMAN Corporation.

[0045] From the viewpoint of improving dispersibility, the average bonding amount of the modifying group in the modified cellulose fiber (A) is preferably 0.01 mmol / g or more, more preferably 0.05 mmol / g or more, still more preferably 0.1 mmol / g or more, still more preferably 0.3 mmol / g or more, still more preferably 0.5 mmol / g or more. From the same viewpoint, it is preferably 3.0 mmol / g or less, more preferably 2.5 mmol / g or less, still more preferably 2.0 mmol / g or less, still more preferably 1.8 mmol / g or less, still more preferably 1.5 mmol / g or less. When two or more arbitrary modifying groups are simultaneously introduced into the modified cellulose fiber (A) as the modifying group, the average bonding amount of the modifying group is preferably such that the total amount of the introduced modifying groups is within the above range.

[0046] From the viewpoints of dispersibility and transparency, the introduction rate of the modifying group in the modified cellulose fiber (A) is preferably 10% or more, and from the viewpoint of obtaining a molded article having excellent mechanical strength, it is preferably 99% or less. When two or more arbitrary modifying groups are simultaneously introduced as the modifying group, it is preferably within the above range as long as the total of the introduction rates does not exceed 100% of the upper limit.

[0047] The average amount of bound modifier and the introduction rate can be adjusted by the amount and type of the compound for introducing the modifier, i.e., the modifying compound, reaction temperature, reaction time, type of solvent, and the like. The average amount of bound modifier (mmol / g) and the introduction rate (%) refer to the amount and ratio of the modifier introduced (bound) to the ionic group in the modified cellulose fiber (A). The average amount of bound modifier and the introduction rate are calculated, for example, by the method described in the examples below when the ionic group is an anionic group.

[0048] (Method for producing modified cellulose fiber (A)) The modified cellulose fiber (A) can be produced according to a known method without particular limitation as long as a modifying group can be introduced into the ionic group of the cellulose fiber containing an ionic group. For example, when the ionic group is a carboxy group, the modified cellulose fiber (A) can be produced with reference to paragraphs 0017 to 0106 of JP-A-2018-024967. Further, acid anhydrides of dicarboxylic acid compounds such as halogenated acetic acids such as chloroacetic acid, maleic anhydride, succinic anhydride, phthalic anhydride, and adipic anhydride, imidized products of acid anhydrides of compounds having a carboxy group, derivatives of acid anhydrides of compounds having a carboxy group, etc. can be reacted with the cellulose fiber to introduce a carboxy group into the cellulose fiber. When the ionic group is a sulfonic acid group, examples of the method for introducing a sulfonic acid group into the cellulose fiber include a method of adding sulfuric acid to the cellulose fiber and heating it. When the ionic group is a phosphoric acid group, examples of the method for introducing a phosphoric acid group into the cellulose fiber include a method of mixing a powder or aqueous solution of phosphoric acid or a phosphoric acid derivative with the cellulose fiber in a dry or wet state, and a method of adding an aqueous solution of phosphoric acid or a phosphoric acid derivative to a dispersion of the cellulose fiber. Examples of the method for introducing a modifying group include a method of mixing a compound having a modifying group with the cellulose fiber having a phosphoric acid group. When the ionic group is a cationic group, examples of the method for introducing a cationic group into the cellulose fiber include a method of treating the cellulose fiber with a cationizing agent in the presence of an alkali. In the production of the modified cellulose fiber (A), the aspect ratio reduction treatment and the micronization step in JP-A-2018-024967 can be omitted.

[0049] <Modified cellulose fiber (B)> The modified cellulose fiber (B) in the present invention is a modified cellulose fiber in which a modifying group is bonded to the hydroxy group of the cellulose fiber.

[0050] (Modifying group) In the modified cellulose fiber (B), the cellulose fiber and the modifying group are bonded via an ether bond. In the present specification, "bonded via an ether bond" means a state in which the modifying group reacts with the hydroxy group of the cellulose fiber to form an ether bond.

[0051] The modifying group in the modified cellulose fiber (B) is preferably a hydrocarbon group which may have a substituent. Here, in the hydrocarbon group which may have a substituent, examples of the hydrocarbon group include a saturated or unsaturated linear or branched aliphatic hydrocarbon group, an aromatic hydrocarbon group such as a phenyl group, or an alicyclic hydrocarbon group such as a cyclohexyl group. Further, in the hydrocarbon group which may have a substituent in the present invention, examples of the substituent include a halogen atom, an oxyalkylene group such as an oxyethylene group, and a hydroxy group.

[0052] As a preferred embodiment of such a modified cellulose fiber (B) (referred to as "Embodiment 1"), for example, one or more modifying groups selected from the modifying group represented by the following general formula (1) and the modifying group represented by the following general formula (2) are bonded to the cellulose fiber via an ether bond, and those having a cellulose I-type crystal structure can be mentioned. -CH2-CH(R 0 )-R 1 (1) -CH2-CH(R 0 )-CH2-(OA) n -O-R 1 (2) 〔In the formula, R in the general formula (1) and the general formula (2) 0 represents a hydrogen atom or a hydroxy group, R 1 each independently represents a hydrogen atom or a hydrocarbon group having 1 or more carbon atoms, preferably 3 or more and 30 or less carbon atoms, n in the general formula (2) represents a number from 0 to 50, and A represents a linear or branched divalent saturated hydrocarbon group having 1 or more and 6 or less carbon atoms.〕

[0053] As a specific example of Embodiment 1, for example, a modified cellulose fiber represented by the following general formula (3) can be exemplified.

[0054] [Chemical formula]

[0055] [In the formula, R is the same or different and represents hydrogen, or a modifying group selected from the modifying group represented by the general formula (1) and the modifying group represented by the general formula (2). However, the case where all R are simultaneously hydrogen is excluded. m is preferably an integer of 20 or more and 3000 or less.]

[0056] The modified cellulose fiber (B) represented by the general formula (3) has a repeating structure of the cellulose unit into which the modifying group is introduced. As the number of repetitions of the repeating structure, m in the general formula (3) is preferably an integer of 20 or more and 3000 or less from the viewpoint of dispersibility.

[0057] (Hydrocarbon group which may have a substituent) The modified cellulose fiber (B) of Embodiment 1 is introduced with one or more modifying groups selected from the modifying groups represented by the general formula (1) and the following general formula (2) alone or in any combination. In addition, even when the modifying group to be introduced is any one of the modifying group groups, in each modifying group group, the same modifying group or a combination of two or more may be introduced.

[0058] From the viewpoint of dispersibility, R in the general formula (1) and the general formula (2) 0 is preferably a hydroxy group.

[0059] R in the general formula (1) 1 The number of carbon atoms of is preferably 25 or less from the viewpoint of dispersibility. Specifically, examples include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, 2-ethylhexyl group, nonyl group, decyl group, undecyl group, dodecyl group, hexadecyl group, octadecyl group, isooctadecyl group, icosyl group, triacontyl group, phenyl group, methylphenyl group, etc.

[0060] R in the general formula (2) 1The carbon number is preferably 4 or more from the viewpoint of dispersibility, and preferably 27 or less from the viewpoints of availability and reactivity improvement. Specifically, R in the above general formula (1) 1 is the same as that described above.

[0061] In general formula (2), A forms an oxyalkylene group with an adjacent oxygen atom. The carbon number of A is preferably 2 or more from the viewpoints of availability and cost, and preferably 4 or less from the same viewpoints. Specifically, examples include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, etc.

[0062] In general formula (2), n represents the number of moles of alkylene oxide added. n is preferably 3 or more from the viewpoints of dispersibility, availability, and cost, and preferably 40 or less from the same viewpoints.

[0063] As the combination of A and n in general formula (2), from the viewpoint of dispersibility, preferably, A is a linear or branched divalent saturated hydrocarbon group having 2 to 3 carbon atoms, and n is a combination of a number from 0 to 20.

[0064] Specific examples of the modifying group represented by general formula (1) include, for example, a pentyl group, a hexyl group, an octyl group, a 2-ethylhexyl group, a decyl group, a dodecyl group, a tetradecyl group, a hexadecyl group, an octadecyl group, an isooctadecyl group, an icosyl group, a propylhydroxyethyl group, a butylhydroxyethyl group, a pentylhydroxyethyl group, a hexylhydroxyethyl group, a heptylhydroxyethyl group, an octylhydroxyethyl group, a 2-ethylhexylhydroxyethyl group, a nonylhydroxyethyl group, a decylhydroxyethyl group, an undecylhydroxyethyl group, a dodecylhydroxyethyl group, a hexadecylhydroxyethyl group, an octadecylhydroxyethyl group, an isooctadecylhydroxyethyl group, an icosylhydroxyethyl group, a triacontylhydroxyethyl group, etc.

[0065] Specific examples of the modifying group represented by the general formula (2) include, for example, 3-butoxy-2-hydroxy-propyl group, 3-hexethoxyethyleneoxy-2-hydroxy-propyl group, 3-hexethoxy-2-hydroxy-propyl group, 3-octethoxyethyleneoxy-2-hydroxy-propyl group, 3-octethoxy-2-hydroxy-propyl group, 6-ethyl-3-hexethoxy-2-hydroxy-propyl group, 6-ethyl-3-hexethoxyethyleneoxy-2-hydroxy-propyl group, 3-decethoxyethyleneoxy-2-hydroxy-propyl group, 3-decethoxy-2-hydroxy-propyl group, 3-undecethoxyethyleneoxy-2-hydroxy-propyl group, 3-undecethoxy-2-hydroxy-propyl group, 3-dodecethoxyethyleneoxy-2-hydroxy-propyl group, 3-dodecethoxy-2-hydroxy-propyl group, 3-hexadecethoxyethyleneoxy-2-hydroxy-propyl group, 3-hexadecethoxy-2-hydroxy-propyl group, 3-octadecethoxyethyleneoxy-2-hydroxy-propyl group, 3-octadecethoxy-2-hydroxy-propyl group, and the like. The number of moles of alkylene oxide added may be 0 or more and 50 or less. For example, substituents having an oxyalkylene group such as ethylene oxide described above with an added mole number of 10, 12, 13, or 20 moles are exemplified.

[0066] (Molar substitution degree (MS)) In the modified cellulose fiber (B) of Embodiment 1, the molar amount (molar substitution degree: MS) of the modifying group introduced per 1 mole of the anhydroglucose unit of cellulose cannot be generally limited by the type of the modifying group. From the viewpoint of dispersibility, it is preferably 0.0001 mole or more, more preferably 0.01 mole or more, still more preferably 0.1 mole or more. Also, having a cellulose I-type crystal structure, from the same viewpoint, it is preferably 1.5 moles or less, more preferably 1.2 moles or less, still more preferably 1 mole or less. Here, when the bonded modifying group is composed of a plurality of types of modifying groups, the MS of the bonded modifying group is the sum of the MS of each modifying group. In the present specification, the MS of the modifying group in the modified cellulose fiber (B) can be measured according to the method described in the examples below.

[0067] <Method for producing modified cellulose fiber (B)> The modified cellulose fiber (B) in the present invention is such that, as described above, a modifying group, preferably a hydrocarbon group which may have the above-mentioned modifying group, is bonded to the cellulose fiber via an ether bond. However, the introduction of the modifying group can be carried out according to a known method without particular limitation. Hereinafter, specific examples of the method for producing the modified cellulose fiber (B) of Mode 1 will be described.

[0068] (Method for producing modified cellulose fiber (B) of Mode 1) As a specific example of the method for producing the modified cellulose fiber (B) of Mode 1, there is an aspect in which a specific compound is reacted with the raw material cellulose fiber in the presence of a base.

[0069] Further, from the viewpoint of reducing the number of manufacturing steps, cellulose fibers that have been refined in advance may be used as the raw material cellulose fibers. In that case, the average fiber diameter is preferably 1 nm or more from the viewpoints of availability and cost. Also, although the upper limit is not particularly set, it is preferably 500 nm or less from the viewpoint of handleability.

[0070] (Base) The base is not particularly limited, but from the viewpoint of promoting the etherification reaction, one or more selected from the group consisting of alkali metal hydroxides, alkaline earth metal hydroxides, primary to tertiary amines, quaternary ammonium salts, imidazole and its derivatives, pyridine and its derivatives, and alkoxides are preferred. Specifically, the bases described in paragraphs 0053 to 0058 of JP-A-2017-053077 can be mentioned.

[0071] The amount of the base is preferably 0.01 equivalent or more from the viewpoint of promoting the etherification reaction with respect to the anhydroglucose unit of the raw material cellulose fiber, and preferably 10 equivalents or less from the viewpoint of manufacturing cost.

[0072] Note that the mixing of the cellulose fibers and the base of the raw materials may be carried out in the presence of a solvent. The solvent is not particularly limited, and examples thereof include water, isopropanol, t-butanol, dimethylformamide, toluene, methyl isobutyl ketone, acetonitrile, dimethyl sulfoxide, dimethylacetamide, 1,3-dimethyl-2-imidazolidinone, hexane, 1,4-dioxane, and mixtures thereof.

[0073] The temperature and time are not particularly limited as long as the cellulose fibers and the base of the raw materials can be uniformly mixed.

[0074] Next, a modifying compound (also referred to as an "etherifying agent" in this specification), preferably a compound for introducing a hydrocarbon group which may have a substituent, is added to the mixture of the cellulose fibers and the base of the raw materials obtained above, and the cellulose fibers of the raw materials are reacted with such a compound. As such a compound, it is preferable to use a compound having a reactive cyclic structural group, and more preferably to use a compound having an epoxy group.

[0075] Examples of the compound capable of bonding the modifying group represented by the general formula (1) via an ether bond include the alkylene oxide compounds described in paragraphs 0079 to 0084 of JP-A-2017-053077.

[0076] Examples of the compound capable of bonding the modifying group represented by the general formula (2) via an ether bond include the glycidyl ether compounds described in paragraphs 0085 to 0091 of JP-A-2017-053077.

[0077] The amount of the modifying compound can be determined by the desired introduction rate of the modifying group in the obtained modified cellulose fiber (B). From the viewpoint of reactivity, it is preferably 0.01 equivalent or more with respect to the anhydroglucose unit of the cellulose fibers of the raw materials, and from the viewpoint of production cost, it is preferably 10 equivalents or less.

[0078] (Etherification reaction) The etherification reaction between the compound and the raw material cellulose fiber can be carried out by mixing the two in the presence of a solvent. There is no particular limitation on the solvent, and the solvents exemplified as those that can be used when the base is present can be used. For details of the etherification reaction, reference can be made to the descriptions in paragraphs 0070 to 0075 of JP-A-2017-053077.

[0079] The modified cellulose fiber (B) of Embodiment 1 thus obtained may be subjected to a known micronization treatment, for example, treatment using a high-pressure homogenizer or the like in an organic solvent.

[0080] Regarding either of the above-mentioned modified cellulose fibers (A) and (B), the modified cellulose fiber can be used in the form of a dispersion, or the solvent can be removed from the dispersion by drying or the like to obtain a dried powdered modified cellulose fiber, which can also be used. Here, "powdered" means a powdered state in which the modified cellulose fibers are aggregated and does not mean cellulose particles.

[0081] Examples of the powdered modified cellulose fiber include a dried product obtained by drying the dispersion of the cellulose fiber as it is; a product obtained by pulverizing the dried product by mechanical treatment; a product obtained by pulverizing the dispersion of the cellulose fiber by a known spray drying method; a product obtained by pulverizing the dispersion of the cellulose fiber by a known freeze drying method, and the like. The spray drying method is a method of spraying and drying the dispersion of the cellulose fiber in the air.

[0082] <Properties of Modified Cellulose Fiber> Due to the use of natural cellulose fiber as its raw material, the modified cellulose fiber has a cellulose I crystal structure. Cellulose I is the crystal form of natural cellulose, and the cellulose I crystallinity means the ratio of the amount of the cellulose I crystal region in the whole cellulose. The presence or absence of the cellulose I crystal structure can be determined by the presence of a peak at 2θ = 22.6° in X-ray diffraction measurement.

[0083] From the perspective of dispersibility, the crystallinity of type I cellulose in the modified cellulose fiber is preferably 30% or more, more preferably 35% or more, still more preferably 40% or more, and even more preferably 45% or more. From the perspective of the cost of the cellulose raw material used, it is preferably 95% or less, more preferably 90% or less, still more preferably 85% or less, and even more preferably 80% or less. In this specification, the crystallinity of type I cellulose in cellulose fibers, modified cellulose fibers, etc. is specifically measured by the method described in the examples below.

[0084] From the perspective of production efficiency and improvement of mechanical properties, the average fiber length of the modified cellulose fiber is preferably 10 nm or more, more preferably 20 nm or more, still more preferably 50 nm or more. On the other hand, from the perspective of dispersibility, it is preferably 500 nm or less, more preferably 400 nm or less, still more preferably 300 nm or less. The average fiber length of the modified cellulose fiber can be measured by the method described in the examples below.

[0085] From the perspective of production efficiency and improvement of mechanical properties, the average fiber diameter of the modified cellulose fiber is preferably 1 nm or more, more preferably 2 nm or more, still more preferably 3 nm or more. From the perspective of dispersibility, it is preferably 30 nm or less, more preferably 20 nm or less, still more preferably 10 nm or less, and even more preferably 5 nm or less. The average fiber diameter of the modified cellulose fiber can be measured by the method described in the examples below.

[0086] From the perspective of production efficiency and improvement of mechanical properties, the average aspect ratio of the modified cellulose fiber is preferably 1 or more, more preferably 5 or more, still more preferably 8 or more, and even more preferably 35 or more. From the perspective of dispersibility, it is preferably 100 or less, more preferably less than 100, still more preferably 80 or less, and even more preferably 55 or less, and even more preferably 50 or less. The average aspect ratio of the modified cellulose fiber can be measured by the method described in the examples below.

[0087] In the thiol compound-containing composition of the present invention, the content of the thiol compound is preferably 50% by mass or more, more preferably 70% by mass or more, still more preferably 80% by mass or more, from the viewpoint of containing the thiol compound. Further, from the viewpoint of containing the modified cellulose fiber, it is preferably 99.9% by mass or less, more preferably 99% by mass or less, still more preferably 98% by mass or less.

[0088] In the thiol compound-containing composition of the present invention, the content of the modified cellulose fiber is preferably 0.01% by mass or more, more preferably 0.1% by mass or more, still more preferably 1% by mass or more, from the viewpoint of expressing the effect of the modified cellulose fiber, and preferably 50% by mass or less, more preferably 30% by mass or less, still more preferably 10% by mass or less, from the viewpoint of dispersibility.

[0089] In the thiol compound-containing composition of the present invention, the mass ratio of the modified cellulose fiber to the thiol compound is preferably 0.001 or more, more preferably 0.005 or more, still more preferably 0.01 or more, from the viewpoint of expressing the effect of the modified cellulose fiber, and preferably 0.3 or less, more preferably 0.2 or less, still more preferably 0.1 or less, from the viewpoint of dispersibility.

[0090] Note that, when two or more kinds of modified cellulose fibers are used, the content of the modified cellulose fibers refers to the total amount, and when two or more kinds of thiol compounds are used, the content of the thiol compounds refers to the total amount. For the content of the modified cellulose fiber and the mass ratio of the modified cellulose fiber to the thiol compound in the thiol compound-containing composition, the cellulose fiber (converted amount) in the modified cellulose fiber is used in order not to include the modifying group.

[0091] The thiol compound-containing composition of the present invention may optionally contain components such as a plasticizer, a filler, a pigment, a thixotropy-imparting agent, a process oil, a reinforcing material, an aggregate, a curing accelerator, a flame retardant, a thickener, a leveling agent, a polymerization catalyst, an internal mold release agent, a light stabilizer, an ultraviolet absorber, an antioxidant, a coloring inhibitor, and a dye. These other components may be used alone or in combination of two or more.

[0092] [Method for producing a thiol compound-containing composition] The method for producing a thiol compound-containing composition of the present invention is not particularly limited, but a production mode including a step of refining a modified cellulose fiber having an average fiber length exceeding 500 nm in a thiol compound is preferably exemplified.

[0093] In this production mode, the modified cellulose fiber to be subjected to the refining treatment is at least one selected from the group consisting of the above-described modified cellulose fiber (A) and modified cellulose fiber (B). Further, as the modified cellulose fiber to be subjected to the refining treatment, from the viewpoint of dispersibility, it is preferable to use a modified cellulose fiber that has been short-fibered within a range of an average fiber length of 1 μm or more and 1000 μm or less. The average fiber length of such short-fiber cellulose fiber is preferably 10 μm or more, more preferably 20 μm or more, still more preferably 30 μm or more, still more preferably 50 μm or more, and is preferably 1000 μm or less, more preferably 800 μm or less, still more preferably 500 μm or less, still more preferably 400 μm or less. Further, the average fiber diameter is preferably 1 μm or more, more preferably 3 μm or more, still more preferably 5 μm or more, and is preferably 300 μm or less, more preferably 100 μm or less, still more preferably 60 μm or less.

[0094] As the short-fibering treatment, a known method can be used, and the target cellulose fiber can be short-fibered by alkali hydrolysis treatment, acid hydrolysis treatment, hydrogen peroxide treatment, ultraviolet treatment, electron beam treatment, hydrothermal decomposition treatment, mechanical treatment, enzyme treatment, or the like. Note that the modified cellulose fiber to be subjected to the refining treatment may be short-fibered before introducing the above-described modifying group or ionic group, or may be short-fibered after introduction. For example, a production mode in which an ionic group is introduced into the raw material cellulose fiber, then a short-fibering treatment is performed, and then a modifying group is introduced, and the obtained short-fibered modified cellulose fiber is refined in a thiol compound can be mentioned.

[0095] As the apparatus that can be used for the refining treatment, a known disperser is preferably mentioned. For example For example, agitators equipped with stirring blades, disintegrators, beaters, low-pressure homogenizers, high-pressure homogenizers -, grinder, cutter mill, ball mill, jet mill, roll mill, single shaft kneader , twin-screw kneader, single-screw extruder, twin-screw extruder, ultrasonic mixer, household juicer mixer, etc. The operating conditions of the device can be set appropriately while referring to the attached instruction manual. That's good.

[0096] The thiol compound-containing composition of the present invention has excellent dispersibility for modified cellulose fibers, and therefore can be suitably used for the production of thioester resin compositions and thiourethane resin compositions. The polymerization product of the thiol compound-containing composition of the present invention will be described below.

[0097] [Polymerization product of thiol compound-containing composition] The polymerization product of the thiol compound-containing composition in the present invention is preferably at least one selected from the group consisting of a thioester resin composition and a thiourethane resin composition.

[0098] When the polymerization product of the thiol compound-containing composition is a thioester resin composition, a desired thioester resin composition can be obtained by selecting an aromatic polycarboxylic acid (having two or more carboxyl groups in the molecule), such as terephthalic acid, 2,6-naphthalenedicarboxylic acid, or an aliphatic polycarboxylic acid, such as adipic acid, sebacic acid, or (iso)phthalic acid, depending on the required physical properties and reactivity, and carrying out an appropriate polymerization reaction according to a conventional method.

[0099] When the polymerization product of the thiol compound-containing composition is a thiourethane resin composition, depending on the required physical properties and reactivity, aromatic compounds such as tolylene diisocyanate and diphenylmethane diisocyanate, or aliphatic compounds such as pentamethylene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, isophorone diisocyanate, and tetramethylxylylene diisocyanate (those having two or more isocyanate groups in the molecule) are selected, and a desired thiourethane resin composition can be obtained by appropriately performing a polymerization reaction according to a conventional method.

[0100] The amount of the modified cellulose in the polymerization product of the thiol compound-containing composition of the present invention, in terms of the compounding amount and in terms of cellulose (excluding modifying groups, etc.), is preferably 0.05% by mass or more, more preferably 0.1% by mass or more, and still more preferably 0.15% by mass or more from the viewpoint of physical property expression. Also, from the viewpoint of handleability, it is preferably 35% by mass or less, more preferably 25% by mass or less, and still more preferably 15% by mass or less.

[0101] The catalyst can be appropriately selected according to the type of the resin. For example, as the catalyst for the thiourethane composition, Lewis acids, tertiary amines, organic acids, amine organic acid salts, etc. can be mentioned. The catalyst may be used alone or in combination of two or more.

[0102] The ratio of the catalyst can be appropriately selected according to the type of the curing agent, etc. For example, it is preferably 0.01 to 100 parts by mass with respect to 100 parts by mass of the thiol compound-containing composition.

[0103] 〔Other Components〕 The polymerization product of the thiol compound-containing composition of the present invention may contain, within a range not impairing the effects of the present invention, for example, plasticizers, crystal nucleating agents, fillers (inorganic fillers, organic fillers), hydrolysis inhibitors, flame retardants, antioxidants, lubricants which are hydrocarbon-based waxes and anionic surfactants, ultraviolet absorbers, antistatic agents, antifogging agents, light stabilizers, pigments, fungicides, antibacterial agents, foaming agents, internal mold release agents, anti-coloring agents, surfactants; starches, polysaccharides such as alginic acid; natural proteins such as gelatin, glue, casein; inorganic compounds such as tannins, zeolites, ceramics, metal powders; fragrances; flow regulators; leveling agents; conductive agents; ultraviolet dispersants; deodorants and the like. Furthermore, other polymer materials and other compositions can be added within a range not inhibiting the effects of the present invention.

[0104] The polymerization product of the thiol compound-containing composition of the present invention can be molded by appropriately using known molding methods such as coating molding, extrusion molding, injection molding, press molding, casting molding, or solvent casting method.

Examples

[0105] Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples. Note that "normal pressure" means 101.3 kPa and "normal temperature" means 25°C.

[0106] 〔Average fiber diameter, average fiber length, and average aspect ratio of anionic modified cellulose fibers, short-fibrillated anionic modified cellulose fibers, and micronized modified cellulose fibers〕 Deionized water or DMF is added to the above-mentioned cellulose fiber or the thiol compound-containing composition containing the above-mentioned cellulose fiber to prepare a dispersion having a concentration of 0.0001% by mass. The dispersion is dropped onto mica and dried to obtain an observation sample. Using an atomic force microscope (AFM, Nanoscope III Tapping mode AFM, manufactured by Digital instrument, and a probe manufactured by Nanoworld Point Probe (NCH)), the fiber height of the cellulose fiber in the observation sample (the difference in height between the places where the fiber is present and the places where there is no fiber) is measured. At this time, in the microscopic image where the cellulose fiber can be confirmed, 100 cellulose fibers are randomly extracted, and the number average fiber diameter is calculated from their fiber heights. 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.

[0107] 〔Average fiber diameter and average fiber length of the raw material cellulose fiber〕 Deionized 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 meter (manufactured by Jasco International Co., Ltd., product name: IF-3200), front lens: 2 times, telecentric zoom lens: 1 time, 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: 15% conditions for measurement. 100 cellulose fibers are measured, and their average ISO fiber diameter is taken as the average fiber diameter, and the average ISO fiber length is taken as the average fiber length for calculation.

[0108] 〔Solid content in the dispersion〕 It is measured using a halogen moisture meter (manufactured by Shimadzu Corporation; product name "MOC-120H"). The measurement is performed every 30 seconds at a constant temperature of 150 °C for 1 g of the sample, and the value at which the mass loss becomes 0.1% or less of the initial amount of the sample is taken as the solid content.

[0109] 〔Anionic group content of anionic modified cellulose fiber and modified cellulose fiber〕 Take 0.5 g of the cellulose fibers to be measured with a dry mass into a beaker, add deionized water or a mixed solvent of methanol / water = 2 / 1 (volume ratio) to make a total of 55 mL, and add 5 mL of 0.01 M aqueous sodium chloride solution thereto to prepare a dispersion. Stir the dispersion until the cellulose fibers to be measured are sufficiently dispersed. Add 0.1 M hydrochloric acid to this dispersion to adjust the pH to 2.5 - 3, and using an automatic titrator (manufactured by Toa DKK Corporation, trade name "AUT-701"), add 0.05 M aqueous sodium hydroxide solution dropwise to the dispersion under the condition of a waiting time of 60 seconds, and measure the conductivity and pH values every minute. Continue the measurement until the pH reaches about 11 to obtain a conductivity curve. From this conductivity curve, obtain the titration amount of sodium hydroxide, and calculate the anionic group content of the cellulose fibers to be measured by the following formula. Anionic group content (mmol / g) = [Titration amount of aqueous sodium hydroxide solution (mL) × Concentration of aqueous sodium hydroxide solution (0.05 M)] / [Mass of cellulose fibers to be measured (0.5 g)]

[0110] 〔Average binding amount and introduction rate of modifying groups of modified cellulose fiber (A)〕 The average binding amount of the modifying group is determined by the following IR measurement method, and the average binding amount and introduction rate are calculated by the following formula. For the IR measurement, specifically, the infrared absorption spectrum of the dried modified cellulose fiber is measured by the ATR method using an infrared absorption spectrometer (IR) (manufactured by Thermo Fisher Scientific, Nicolet 6700), and the average binding amount and introduction rate of the modifying group are calculated by Formulas A and B. The following shows the case where the anionic group is a carboxy group, that is, the case of oxidized cellulose fiber. The following "peak intensity at 1720 cm -1 is the peak intensity derived from the carbonyl group. In the case of an anionic group other than the carboxy group, the wavenumber value may be appropriately changed to calculate the average binding amount and introduction rate of the modifying group. <Formula A-1 (in the case of ionic bond)> Average binding amount of modifying group (mmol / g) = a × (b - c) ÷ b a: Carboxy group content of oxidized cellulose fiber (mmol / g) b: Peak intensity at 1720 cm of oxidized cellulose fiber -1Peak intensity c: Peak intensity of the modified cellulose fiber at 1720 cm -1 Peak intensity <Formula A-2 (in the case of amide bond)> Average amount of bonded modifying group (mmol / g) = d - e d: Carboxyl group content (mmol / g) of the oxidized cellulose fiber e: Carboxyl group content (mmol / g) of the modified cellulose fiber <Formula B> Introduction rate of the modifying group (mol%) = 100 × f / g f: Average amount of bonded modifying group (mmol / g) g: Carboxyl group content (mmol / g) of the oxidized cellulose fiber

[0111] 〔Degree of introduction of substituents (MS) in the modified cellulose fiber (B)〕 First, calculate the mass percentage of the introduced substituent contained in the cellulose to be measured according to the Zeisel method, which is known as a method for analyzing the average number of added moles of the alkoxy group of cellulose ether described in Analytical Chemistry, Vol. 51, No. 13, 2172 (1979), "The Fifteenth Revised Japanese Pharmacopoeia (in the section on the analysis method of hydroxypropyl cellulose)", etc. The procedure is shown below. (i) Add 0.1 g of n-tetradecane to a 200 mL volumetric flask, and make up to the mark with hexane to prepare an internal standard solution. (ii) Weigh accurately 70 mg of the cellulose to be measured that has been purified and dried and 80 mg of adipic acid into a 10 mL vial, add 2 mL of hydroiodic acid, and seal tightly. (iii) Heat the mixture in the above vial at 160 °C for 1 hour with stirring using a stirrer chip. (IV) After heating, sequentially inject 2 mL of the internal standard solution and 2 mL of diethyl ether into the vial, and stir at room temperature for 1 minute. (v) Analyze the upper layer (diethyl ether layer) of the mixture separated into two phases in the vial by gas chromatography (manufactured by SHIMADZU Corporation, product name: GC2010Plus). (vi) Analyze the cellulose to be measured in the same manner as in (ii) to (v), except that the cellulose to be measured is changed to 5 mg, 10 mg, and 15 mg of the etherifying agent used for its modification, respectively, and create a calibration curve for the etherifying agent. (vii) Quantify the substituents contained in the cellulose to be measured from the created calibration curve and the analysis results of the cellulose to be measured. The analysis conditions are as follows.

[0112] Column: Manufactured by Agilent Technologies, trade name: DB-5 (12 m, 0.2 mm × 0.33 μm) Column temperature: 30 °C (10 min Hold) → 10 °C / min → 300 °C (10 min Hold) Injector temperature: 300 °C Detector temperature: 300 °C Injection volume: 1 μL

[0113] Next, calculate the degree of molar substitution (MS) using the following formula (1) or (2) from the introduced mass of the obtained substituents. Formula (1): When there is one type of substituent to be introduced MS = (W / Mw) / ((100 - W) / 162.14) W: Introduced mass of the substituent in the modified cellulose fiber (mass %) Mw: Molecular weight of the introduced etherifying agent (g / mol)

[0114] Formula (2): When there are two types of substituents to be introduced MS1 = (W1 / Mw1) / ((100 - W1 - W2) / 162.14) MS2 = (W2 / Mw2) / ((100 - W1 - W2) / 162.14) MS1: Degree of molar substitution of the first type of substituent MS2: Degree of molar substitution of the second type of substituent W1: Introduced mass of the first type of substituent in the modified cellulose fiber (mass %) W2: Introduced mass of the second type of substituent in the modified cellulose fiber (mass %) Mw1: Molecular weight of the first type of introduced etherifying agent (g / mol) Mw2: Molecular weight (g / mol) of the second type of etherifying agent introduced

[0115] [Cellulose fiber (converted amount) in the modified cellulose fiber] The cellulose amount (converted amount) in the modified cellulose fiber refers to the amount of cellulose in the modified cellulose fiber excluding the modifying groups. In the modified cellulose fiber of the present invention, since the formula weight of the modifying group may be considerably large (for example, larger than the molecular weight of glucose), when it is appropriate to explain by excluding the difference in the formula weight of the modifying group in this specification, it is expressed not by the amount of the modified cellulose fiber but by the amount (converted amount) of cellulose constituting the modified cellulose fiber. The cellulose fiber (converted amount) in the modified cellulose fiber is measured by the following method.

[0116] (1) When there is one type of "compound for modification" added The cellulose fiber amount (converted amount) is calculated by the following formula E. <Formula E>[[]] Cellulose fiber amount (converted amount) (g) = Mass of modified cellulose fiber (g) / [1 + Molecular weight of compound for modification (g / mol) × Average binding amount of modifying group (mmol / g) × 0.001] (2) When there are two or more types of "compounds for modification" added Considering the molar ratio of each compound (that is, the molar ratio when the total molar amount of the added compounds is 1), the cellulose fiber amount (converted amount) is calculated.

[0117] In addition, when the bonding mode between the cellulose fiber and the compound for modification is an ionic bond, in the above formula, the "molecular weight of the compound for modification" refers to the "molecular weight of the entire compound for modification including the copolymerized part" when the compound for modification is a primary amine, secondary amine or tertiary amine, and refers to "(molecular weight of the entire compound for modification including the copolymerized part) - (molecular weight of the anionic component)" when the compound having a modifying group is a quaternary ammonium compound or phosphonium compound. ​On the other hand, when the bonding mode between the cellulose fiber and the modifying compound is an amide bond, in the above formula, the "molecular weight of the modifying compound" means, when the modifying compound is a primary amine or a secondary amine, "(the molecular weight of the whole compound having a modifying group including the copolymerized part) - 18".

[0118] 〔Confirmation of Crystal Structure in Various Cellulose Fibers〕 The crystal structures of various cellulose fibers such as modified cellulose fibers are confirmed by measuring under the following conditions using an X-ray diffractometer (MiniFlexII manufactured by Rigaku Corporation). The measurement conditions are as follows: X-ray source: Cu / Kα-radiation, tube voltage: 30 kv, tube current: 15 mA, measurement range: diffraction angle 2θ = 5 to 45°, X-ray scan speed: 10° / min. As the measurement sample, the cellulose fiber to be measured is compressed into a pellet with an area of 320 mm 2 × thickness of 1 mm. Also, the crystallinity of the cellulose I-type crystal structure is calculated based on the obtained X-ray diffraction intensity using the following formula C.

[0119] <Formula C> Cellulose I-type crystallinity (%) = [(I 22.6 - I 18.5 ) / I 22.6 × 100 〔In the formula, I 22.6 represents the diffraction intensity of the lattice plane (002 plane) (diffraction angle 2θ = 22.6°) in X-ray diffraction, and I 18.5 represents the diffraction intensity of the amorphous part (diffraction angle 2θ = 18.5°).〕

[0120] On the other hand, when the crystallinity obtained by the above formula C is 35% or less, from the viewpoint of improving the calculation accuracy, it is preferable to calculate based on the following formula D in accordance with the description on P199 - 200 of "Wood Science Experiment Manual" (edited by the Japanese Wood Research Society; published in April 2000). Therefore, when the crystallinity obtained by the above formula C is 35% or less, the value calculated based on the following formula D can be used as the crystallinity.

[0121] <Formula D> Degree of crystallinity of cellulose I type (%) = [Ac / (Ac + Aa)] × 100 〔In the formula, Ac is the total peak area of the lattice planes (002 plane) (diffraction angle 2θ = 22.6°), (011 plane) (diffraction angle 2θ = 15.1°), and (0-11 plane) (diffraction angle 2θ = 16.2°) in X-ray diffraction, Aa is the peak area of the amorphous part (diffraction angle 2θ = 18.5°), and each peak area is obtained by fitting the obtained X-ray diffraction chart with a Gaussian function.〕

[0122] Preparation Example 1 (Preparation of anionic modified cellulose fiber) Bleached kraft pulp of softwood (manufactured by Fletcher Challenge Canada, trade name "Machenzie", CSF 650 ml) was used as the natural cellulose fiber. As TEMPO, a commercially available product (manufactured by ALDRICH, Free radical, 98% by mass) was used. As sodium hypochlorite, a commercially available product (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was used. As sodium bromide, a commercially available product (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was used.

[0123] First, 100 g of bleached kraft pulp fibers of softwood were sufficiently stirred with 9900 g of deionized water, and then 1.25 g of TEMPO, 12.5 g of sodium bromide, and 28.4 g of 5% by mass sodium hypochlorite were added in this order with respect to 10 g of the pulp mass. Using a pH stat, 0.5 M sodium hydroxide was added dropwise to maintain the pH at 10.5. After the reaction was carried out for 120 minutes (20 °C), the addition of sodium hydroxide was stopped to obtain oxidized pulp. The oxidized pulp obtained using deionized water was sufficiently washed and then dehydrated. The anionic group of the obtained anionic modified cellulose fiber was a carboxy group, and the carboxy group content was 1.3 mmol / g. The average fiber diameter of the oxidized cellulose fiber was 41 μm, and the average fiber length was 1058 μm.

[0124] Preparation Example 2 (Preparation of short-fibered anionic modified cellulose fiber) A magnetic stirrer was used to charge 7.2 g of the oxidized cellulose fibers obtained in Preparation Example 1 (in absolute dry mass) into a vial equipped with a stir bar, and deionized water was added until the mass of the treatment liquid reached 360 g. After the obtained mixed solution was stirred at 95 °C for 24 hours, dehydration treatment was performed to obtain short-fibrillated anionic modified cellulose fibers. The anionic groups of the obtained anionic modified cellulose fibers were carboxyl groups, and the carboxyl group content was 1.3 mmol / g. The average fiber diameter of the short-fibrillated cellulose fibers was 41 μm, and the average fiber length was 133 μm.

[0125] Example 1 A magnetic stirrer was used to charge 0.17 g of the short-fibrillated anionic modified cellulose fibers obtained in Preparation Example 2 (in absolute dry mass) into a beaker equipped with a stir bar. Subsequently, 0.21 g of an aliphatic polyetheramine (manufactured by Huntsman Corporation, USA, trade name: Jeffamine M-2070) was charged and dissolved in 10 g of acetone. The obtained mixed solution was stirred at room temperature (25 °C) for 1 hour to obtain a cellulose fiber composite in which the aliphatic polyetheramine was bonded to the anionic modified cellulose fibers. Thereafter, 8 g of a thiol compound (manufactured by Wako Pure Chemical Industries, Ltd., Fuji Pharmaceutical Co., Ltd., grade: pentaerythritol tetrakis(3-mercaptopropionate), molecular weight 488, hereinafter abbreviated as "PETM") was added, and the mixture was further stirred at 25 °C for 1 hour. Using a high-pressure homogenizer (manufactured by Yoshida Kikai Kogyo Co., Ltd., Nanovaita L-ES), the mixture was subjected to dispersion treatment at 150 MPa five times. The solvent was removed from the obtained dispersion to obtain a thiol compound-containing composition containing modified cellulose fibers and PETM. The average fiber diameter of the modified cellulose fibers in the thiol compound-containing composition was 4 nm, the average fiber length was 160 nm, the average aspect ratio was 40, the average binding amount was 1.27 mmol / g, and it had a cellulose I-type crystal structure.

[0126] Example 2 A thiol compound-containing composition was obtained in the same manner as in Example 1, except that 0.11 g of an aliphatic polyetheramine (manufactured by Huntsman Corporation, USA, trade name: Jeffamine M-1000) was charged in Example 1. The average binding amount was 1.27 mmol / g.

[0127] Example 3 A thiol compound-containing composition was obtained in the same manner as in Example 1, except that 0.21 g of an aliphatic polyetheramine (manufactured by Huntsman Corporation, trade name: JEFFAMINE M-2095) was charged as the amine in Example 1. The average binding amount was 1.27 mmol / g.

[0128] Example 4 A thiol compound-containing composition was obtained in the same manner as in Example 1, except that 0.17 g of an aliphatic polyetheramine (manufactured by Huntsman Corporation, trade name: JEFFAMINE M-2070) and 0.01 g of octylamine (manufactured by Fujifilm Wako Pure Chemical Corporation) were charged as the amine in Example 1. The average binding amount was 0.67 mmol / g.

[0129] Example 5 3.12 g of the short-fibrillated anionic modified cellulose fiber obtained in Preparation Example 2 was charged into a beaker equipped with a magnetic stirrer and a stir bar in terms of absolutely dry mass. Subsequently, 8.01 g of an aliphatic polyetheramine (manufactured by Huntsman Corporation, trade name: JEFFAMINE M-2070), 0.71 g of 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM) as a condensing agent, and 0.13 g of N-methylformalin (NMM) were each charged and dissolved in 85 g of DMF, and the reaction solution was reacted at room temperature (25 °C) for 14 hours. After completion of the reaction, filtration was performed, washing was carried out with deionized water to remove the DMT-MM salt, and washing and solvent substitution were performed with acetone to obtain a cellulose fiber composite in which an aliphatic polyetheramine was linked to the fine cellulose fiber via an amide bond. Then, 0.51 g of the cellulose fiber composite in which the aliphatic polyetheramine was linked via an amide bond in terms of absolutely dry mass and 8 g of a thiol compound (PETM) were added, and stirring was further carried out at 25 °C for 1 hour. Using a high-pressure homogenizer (manufactured by Yoshida Kikai Kogyo Co., Ltd., Nanovaita L-ES), dispersion treatment was performed 5 times at 150 MPa. The solvent was removed from the obtained dispersion to obtain a thiol compound-containing composition containing the modified cellulose fiber and PETM. The average binding amount was 0.98 mmol / g.

[0130] Example 6 A thiol compound-containing composition was obtained in the same manner as in Example 5, except that 4.00 g of an aliphatic polyether amine (manufactured by Huntsman Corporation, trade name: JEFFAMINE M-1000) was charged as the amine in Example 5. The average bonding amount was 1.02 mmol / g.

[0131] Example 7 A magnetic stirrer and a beaker equipped with a stir bar were charged with 3.12 g of the short-fibrillated anionic-modified cellulose fibers obtained in Preparation Example 2 in terms of absolute dry mass. Subsequently, 4.86 g of an aliphatic polyetheramine (manufactured by Huntsman Corporation, USA, trade name: JEFFAMINE M-1000), 2.47 g of 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM) as a condensing agent, and 0.49 g of N-methylformalin (NMM) were each charged and dissolved in 71 g of DMF, and the reaction solution was reacted at room temperature (25 °C) for 14 hours. After completion of the reaction, the mixture was filtered, washed with deionized water to remove the DMT-MM salt, and washed and solvent-exchanged with acetone and DMF to obtain a cellulose fiber composite in which the aliphatic polyetheramine was linked to the fine cellulose fibers via an amide bond. Subsequently, 1.56 g of the cellulose fiber composite in which the aliphatic polyetheramine was linked via an amide bond in terms of absolute dry mass, 0.63 g of an aromatic amine (manufactured by Tokyo Chemical Industry Co., Ltd., tritylamine), 1.47 g of DMT-MM, 0.25 g of NMM were dissolved in 35 g of DMF, and the reaction solution was reacted at room temperature (25 °C) for 14 hours. After completion of the reaction, the mixture was filtered, washed with deionized water to remove the DMT-MM salt, and washed and solvent-exchanged with acetone to obtain a cellulose fiber composite in which the aliphatic polyetheramine and the aromatic amine were linked to the fine cellulose fibers via an amide bond. Thereafter, 8 g of a thiol compound (PETM) was added to 0.17 g of the cellulose fiber composite in which the aliphatic polyetheramine and the aromatic amine were linked via an amide bond in terms of absolute dry mass, and the mixture was further stirred at 25 °C for 1 hour. Using a high-pressure homogenizer (manufactured by Yoshida Kikai Kogyo Co., Ltd., Nanovaita L-ES), the mixture was subjected to dispersion treatment at 150 MPa five times. The solvent was removed from the obtained dispersion to obtain a thiol compound-containing composition containing the modified cellulose fibers and PETM. The average binding amount was 1.04 mmol / g.

[0132] Example 8 A thiol compound-containing composition was obtained in the same manner as in Example 7, except that 0.51 g of diphenylpropylamine (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was charged instead of tritylamine in Example 7. The average binding amount was 1.03 mmol / g.

[0133] Example 9 A thiol compound-containing composition was obtained in the same manner as in Example 7, except that 9.71 g of (trade name: JEFFAMINE M-2095, manufactured by Huntsman Corporation, USA) was used instead of JEFFAMINE M-1000 and 0.31 g of diphenylpropylamine was used instead of tritylamine. The average binding amount was 1.04 mmol / g.

[0134] Comparative Example 1 A thiol compound-containing composition was obtained in the same manner as in Example 1, except that no aliphatic polyetheramine was charged in Example 1.

[0135] Test Example 1 (Transparency Evaluation Test) Using the thiol compound-containing compositions obtained in each Example and Comparative Example, the light transmittance of the dispersion was measured as follows, and its transparency was evaluated. The measurement of the light transmittance was carried out under normal temperature and pressure. Specifically, 3 mL of the thiol compound-containing composition was put into a quartz cell with an optical path length of 10 mm, and immediately, using a double-beam spectrophotometer (manufactured by Hitachi High-Technologies Corporation, "U-2910"), the absorbance at a wavelength of 660 nm was measured. The medium used for preparing each dispersion was used as a blank (i.e., light transmittance 100%), and the light transmittance (%) was determined from the absorbance of each dispersion.

[0136] [Table 1]

[0137] It can be seen from Table 1 that the thiol compound-containing compositions of Examples 1 to 9 containing the modified cellulose fibers were all superior in dispersibility and transparency compared to Comparative Example 1 containing unmodified cellulose fibers.

Industrial Applicability

[0138] The thiol compound-containing composition of the present invention can be suitably used for the production of curing agents for epoxy resins, thiourethane resin compositions, thioester resin compositions, and the like.

Claims

1. A thiol compound-containing composition containing a thiol compound and a modified cellulose fiber, wherein the modified cellulose fiber has a cellulose I-type crystal and is one or more selected from the group consisting of the following cellulose fibers (A). Modified cellulose fiber (A): A modified cellulose fiber obtained by bonding a modifying group to an ionic group of a cellulose fiber containing an ionic group

2. The thiol compound-containing composition according to claim 1, wherein the thiol compound is a polythiol compound having two or more thiol groups.

3. A thiol compound-containing composition containing a thiol compound and a modified cellulose fiber, wherein the thiol compound is a polythiol compound having two or more thiol groups, the modified cellulose fiber has a cellulose I-type crystal, and is one or more selected from the group consisting of the following cellulose fibers (B). Modified cellulose fiber (B): A modified cellulose fiber obtained by bonding a modifying group to a hydroxy group of a cellulose fiber

4. The thiol compound-containing composition according to any one of claims 1 to 3, wherein the aspect ratio of the modified cellulose fiber is 100 or less.

5. The thiol compound-containing composition according to any one of claims 1 to 4, wherein the fiber length of the modified cellulose fiber is 500 nm or less.

6. The thiol compound-containing composition according to claim 1 or 2, wherein the ionic group is a carboxy group.

7. The thiol compound-containing composition according to any one of claims 1 to 6, wherein the modifying group contains one or more selected from the group consisting of (a) a hydrocarbon group and (b) a polymer group.

8. A method for producing the thiol compound-containing composition according to any one of claims 1 to 7, comprising a step of refining a modified cellulose fiber having an average fiber length exceeding 500 nm in a thiol compound, wherein the modified cellulose fiber subjected to the refining step is one or more selected from the group consisting of the following modified cellulose fiber (A) and modified cellulose fiber (B). Modified cellulose fiber (A): A modified cellulose fiber obtained by bonding a modifying group to an ionic group of a cellulose fiber containing an ionic group Modified cellulose fiber (B): A modified cellulose fiber obtained by bonding a modifying group to a hydroxy group of a cellulose fiber

9. A polymerization product of the thiol compound-containing composition according to any one of claims 1 to 7.

10. The polymerization product of the thiol compound-containing composition according to claim 9, which is a thioester composition or a thiourethane composition.

Images