Resin composition containing modified cellulose fibers, and method for producing modified cellulose fibers

Abstract

The present invention relates to a method for manufacturing a modified cellulose fiber which, when incorporated into a resin, can improve the heat resistance and strength of the resin; and a resin composition obtained by blending the modified cellulose fiber. A resin composition according to the present invention is obtained by blending: modified cellulose fibers obtained by bonding cellulose fibers to which modifying groups other than silanol groups are bonded, and a silane compound; and a resin.

Description

Technical Field

[0001] This invention relates to a resin composition formulated with modified cellulose fibers. Furthermore, this invention relates to a method for manufacturing modified cellulose fibers. Background Technology

[0002] In recent years, the miniaturization, weight reduction, and thinning of electronic devices that process high-speed, high-capacity information, such as digital home appliances, have become increasingly prevalent. Therefore, the industry demands improvements in the heat resistance or strength of the components that make up these electronic devices.

[0003] For example, it is known that cellulose nanofibers (CNFs) have excellent strength and therefore can function as reinforcing materials when combined with resins in small amounts (Patent Document 1).

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2006-241450 Summary of the Invention

[0007] The present invention relates to the following [1] to

[18] .

[0008] [1] A resin composition comprising the following components:

[0009] Modified cellulose fibers are cellulose fibers bonded with silane compounds and modified with groups other than silanol groups; and

[0010] Resin.

[0011] [2] The resin composition described in [1] above, wherein the silane compound is one or more silane compounds selected from chlorosilane compounds, alkoxysilane compounds, acetoxysilane compounds and silanol compounds.

[0012] [3] The resin composition described in [1] or [2] above, wherein the amount of the silane compound is 50 parts by mass or more relative to 100 parts by mass of the cellulose fiber portion of the cellulose fiber bonded with the modification group other than the silanol group.

[0013] [4] The resin composition described in any one of [1] to [3] above, wherein the amount of modified cellulose in the resin composition is 4.0% by mass or more and 20% by mass or less.

[0014] [5] The resin composition described in any one of [1] to [4] above, wherein the amount of cellulose fiber in the resin composition is 0.1% by mass or more and 20% by mass or less.

[0015] [6] The resin composition described in any one of [1] to [5] above, wherein the amount of resin in the resin composition is 70% by mass or more and 95% by mass or less.

[0016] [7] The resin composition described in any one of [1] to [6] above, wherein the mass ratio of the amount of modified cellulose in the resin composition to the amount of resin (the amount of modified cellulose fiber / the amount of resin) is 5 / 95 or more and 20 / 80 or less.

[0017] [8] The resin composition described in any one of [1] to [7] above, wherein the mass ratio of the amount of cellulose fiber in the resin composition to the amount of resin (amount of cellulose fiber / amount of resin) is 0.1 / 99.9 or more and 20 / 80 or less.

[0018] [9] A resin molded article comprising a resin composition as described in any one of [1] to [8] above.

[0019]

[10] A method for manufacturing modified cellulose fibers, comprising the following steps:

[0020] Step 1: A step of bonding a modifying group other than a silanol group to the ionic group of a cellulose fiber, thereby obtaining a cellulose fiber bonded with the modified group; and

[0021] Step 2: A step of mixing the cellulose fibers with the above-mentioned modified groups with one or more silane compounds selected from chlorosilane compounds, alkoxysilane compounds, acetoxysilane compounds, and silanol compounds; and

[0022] The amount of the silane compound in step 2 is 50 parts by mass or more, relative to 100 parts by mass of the cellulose fiber portion of the cellulose fiber bonded with the modified group.

[0023]

[11] A method for manufacturing modified cellulose fibers, comprising the following steps:

[0024] Step 3: A step of mixing cellulose fibers with ionic groups with one or more silane compounds selected from chlorosilane compounds, alkoxysilane compounds, acetoxysilane compounds, and silanol compounds to obtain cellulose fibers bonded with silane compounds; and

[0025] Step 4: A step of bonding modifying groups other than silanol groups to the ionic groups of the cellulose fibers bonded with silane compounds, thereby obtaining modified cellulose fibers; and

[0026] The amount of the silane compound in step 3 is 50 parts by mass or more, relative to 100 parts by mass of the cellulose fiber portion of the cellulose fiber with ionic groups.

[0027]

[12] A modified cellulose fiber manufactured by the manufacturing method described in

[10] or

[11] above.

[0028]

[13] A composition comprising the modified cellulose fibers as described in

[12] above.

[0029]

[14] The composition described in

[13] above further comprises an organic solvent and / or a resin.

[0030]

[15] An additive for resin comprising modified cellulose fibers as described in

[12] above.

[0031]

[16] The resin additives described in

[15] above also contain organic solvents.

[0032]

[17] A method for manufacturing a resin composition, comprising the following steps:

[0033] Step 5: A step of bonding a modifying group other than a silanol group to the ionic group of a cellulose fiber, thereby obtaining a cellulose fiber bonded with the modified group; and

[0034] Step 6: A step of mixing one or more silane compounds selected from chlorosilane compounds, alkoxysilane compounds, acetoxysilane compounds, and silanol compounds, the aforementioned cellulose fibers with bonded modification groups, and the resin; and

[0035] The amount of the silane compound in step 6 is 50 parts by mass or more, relative to 100 parts by mass of the cellulose fiber portion of the cellulose fiber bonded with the modified group.

[0036]

[18] A method for manufacturing a resin composition, comprising the following steps:

[0037] Step 7: A step of mixing cellulose fibers with ionic groups with one or more silane compounds selected from chlorosilane compounds, alkoxysilane compounds, acetoxysilane compounds, and silanol compounds to obtain cellulose fibers bonded with silane compounds; and

[0038] Step 8: A step of bonding modifying groups other than silanol groups to the ionic groups present in the cellulose fibers bonded with silane compounds, thereby obtaining modified cellulose fibers; and

[0039] The amount of the silane compound in step 7 is 50 parts by mass or more, relative to 100 parts by mass of the cellulose fiber portion of the cellulose fiber with ionic groups. Detailed Implementation

[0040] Currently, various types of resins are used to construct components of electronic devices, each with different characteristics or properties. When cellulose fibers such as CNF are compounded with resins, poor dispersibility in the resin can sometimes lead to the formation of aggregates, raising concerns about reduced strength.

[0041] This invention relates to a method for manufacturing modified cellulose fibers, which, when incorporated into a resin, can improve the resin's heat resistance and strength.

[0042] According to the present invention, a method for manufacturing modified cellulose fibers can be provided, which, when incorporated into a resin, can improve the resin's heat resistance and strength.

[0043] The inventors studied the combination of resin, conventional modified cellulose fibers, and various components, and found that by bonding specific silane compounds, such as silanol-based silane compounds obtained through hydrolysis, to cellulose fibers, the heat resistance and mechanical strength of the resin were unexpectedly improved, thus completing the present invention.

[0044] The mechanism underlying this effect is presumed, but not definitively established. Specifically, it is presumed that the functional groups in the cross-linked resin, formed during resin curing, react with the hydroxyl groups present in the conventional modified cellulose fibers, thereby hindering cross-linking. Therefore, it is presumed that by pre-reacting the hydroxyl groups present in the conventional modified cellulose fibers with the silane compound during resin curing, the resistance to cross-linking caused by the aforementioned hydroxyl groups can be reduced, resulting in improved heat resistance and mechanical strength of the resin.

[0045] A. A method for manufacturing modified cellulose fibers, including steps 1 and 2.

[0046] One embodiment of the method for manufacturing the modified cellulose fiber of the present invention is a method for manufacturing modified cellulose fiber, which includes the following steps:

[0047] Step 1: A step of bonding a modifying group other than a silanol group to the ionic group of a cellulose fiber, thereby obtaining a cellulose fiber bonded with the modified group; and

[0048] Step 2: A step of mixing the cellulose fibers with the above-mentioned modified groups with one or more silane compounds selected from chlorosilane compounds, alkoxysilane compounds, acetoxysilane compounds, and silanol compounds; and

[0049] The amount of the silane compound in step 2 is 50 parts by mass or more, relative to 100 parts by mass of the cellulose fiber portion of the cellulose fiber bonded with the modified group.

[0050] [Cellulose fibers with ionic groups]

[0051] The main properties of the "cellulose fiber with ionic groups" supplied to process 1 are as follows.

[0052] [Crystal Structure]

[0053] From the viewpoint of the strength performance of the cured resin, cellulose fibers with ionic groups preferably have a type I cellulose crystalline structure. From the viewpoint of the strength performance of the cured resin, the crystallinity of the cellulose fibers with ionic groups is preferably 10% or more, more preferably 15% or more, further preferably 20% or more, further preferably 30% or more, further preferably 40% or more, and further preferably 50% or more. Furthermore, from the viewpoint of raw material availability, it is preferably 90% or less, more preferably 85% or less, and further preferably 80% or less. It should be noted that in this specification, the crystallinity of various cellulose fibers refers to the type I cellulose crystallinity calculated based on the diffraction intensity value obtained by X-ray diffraction, which can be measured according to the method described in the following examples. It should be noted that type I cellulose is the crystal form of natural cellulose, and the type I cellulose crystallinity refers to the proportion of crystalline regions in the total cellulose fiber. The presence or absence of a type I cellulose crystalline structure can be determined by the presence of a peak at 2θ = 22.6° in X-ray diffraction measurements.

[0054] [Average fiber diameter]

[0055] From the viewpoints of processability, availability, and cost, cellulose fibers with ionic groups are preferably 1 μm or more, more preferably 5 μm or more, and from the viewpoints of improving processability and dispersibility, preferably 300 μm or less, more preferably 100 μm or less, and even more preferably 60 μm or less.

[0056] Average fiber length

[0057] From the viewpoint of the strength performance of the cured resin, the average fiber length of the cellulose fiber having ionic groups is preferably 1 μm or more, more preferably 5 μm or more, and even more preferably 10 μm or more. On the other hand, from the viewpoint of processability, it is preferably 500 μm or less, more preferably 400 μm or less, and even more preferably 300 μm or less.

[0058] The average fiber diameter and average fiber length of the cellulose fibers with ionic groups were determined by the methods described in the following examples.

[0059] [Ionic radical]

[0060] Examples of ionic groups include anionic and cationic groups. Examples of anionic groups include carboxyl groups, sulfonic acid groups, and (phosphite) groups. Examples of cationic groups include groups containing ononium such as ammonium, phosphonium, or sulfonium. Ionic groups can be introduced individually or in combination with two or more groups.

[0061] From the viewpoint of efficiency in introducing ionic groups into cellulose fibers, anionic groups are preferred, and carboxyl groups are more preferred.

[0062] [Preparation of cellulose fibers with ionic groups]

[0063] The "cellulose fiber with ionic group" supplied to process 1 can be prepared by introducing the desired ionic group into the cellulose fiber of the raw material.

[0064] [Cellulose fiber]

[0065] Cellulose fibers, which are raw materials for cellulose fibers with ionic groups, are preferably natural cellulose fibers from an environmental perspective. Examples include: wood pulp such as coniferous pulp and broadleaf pulp; cotton pulp such as cotton lint and cottonseed lint; non-wood pulp such as wheat straw pulp and bagasse pulp; and bacterial cellulose. These can be used alone or in combination of two or more.

[0066] The average fiber diameter of the cellulose fibers in the raw material is not particularly limited, but from the viewpoint of processability and cost, it is preferably 5 μm or more, more preferably 7 μm or more, and from the same viewpoint, it is preferably 500 μm or less, more preferably 300 μm or less. The average fiber diameter of the cellulose fibers in the raw material is determined by the method described in the following examples.

[0067] Furthermore, the average fiber length of the cellulose fibers in the raw material is not particularly limited, but from the viewpoint of availability and cost, it is preferably 5 μm or more, more preferably 25 μm or more, and from the same viewpoint, it is preferably 5,000 μm or less, more preferably 3,000 μm or less. The average fiber length of the cellulose fibers in the raw material can be measured according to the method described in the following examples.

[0068] [Methods for introducing ionic radicals]

[0069] As a method for introducing an ionic group, such as a carboxyl group as an anionic group, into cellulose fibers, the following methods can be cited: oxidizing the hydroxyl groups of cellulose fibers to convert them into carboxyl groups; or reacting at least one of a compound having a carboxyl group, an anhydride of a compound having a carboxyl group, and derivatives thereof with the hydroxyl groups of cellulose fibers.

[0070] In this specification, cellulose fibers incorporating anionic groups are referred to as "anionic modified cellulose fibers".

[0071] As a method for oxidizing the hydroxyl groups of cellulose fibers, for example, the following method can be used: using 2,2,6,6-tetramethyl-1-piperidine-N-hydroxyl group (TEMPO) as a catalyst, as described in Japanese Patent Application Publication No. 2015-143336 or Japanese Patent Application Publication No. 2015-143337, an oxidant such as sodium hypochlorite and a bromide such as sodium bromide react with the cellulose fibers of the raw material.

[0072] By using TEMPO as a catalyst to oxidize cellulose fibers, the hydroxymethyl group at the C6 position of the glucose unit constituting the cellulose fiber is selectively converted into a carboxyl group. Cellulose fibers in which the hydroxymethyl group at the C6 position of the glucose unit is selectively converted into a carboxyl group are called "TEMPO-oxidized cellulose fibers". TEMPO-oxidized cellulose fibers are a suitable example of cellulose fibers with ionic groups in this invention.

[0073] [Carboxyl content]

[0074] The content of ionic groups, i.e., carboxyl groups, in TEMPO oxidized cellulose fibers is preferably 0.1 mmol / g or more, more preferably 0.4 mmol / g or more, even more preferably 0.6 mmol / g or more, even more preferably 0.7 mmol / g or more, and even more preferably 0.8 mmol / g or more, from the viewpoint of introducing stable modifying groups. Furthermore, from the viewpoint of improving processability, it is preferably 3 mmol / g or less, more preferably 2.5 mmol / g or less, even more preferably 2 mmol / g or less, even more preferably 1.9 mmol / g or less, and even more preferably 1.8 mmol / g or less. It should be noted that "carboxyl group content" refers to the total amount of carboxyl groups in the glucose portion constituting the cellulose fiber, specifically determined by the method described in the examples below.

[0075] [Process 1]

[0076] Step 1 in this invention is the following step: bonding a modification group other than a silanol group to the ionic group of the cellulose fiber, thereby obtaining a cellulose fiber bonded with the modification group.

[0077] [Modifying groups other than silanol groups]

[0078] Specific examples of "modifying groups other than silanol groups" in this invention include (a) hydrocarbon groups and (b) polymer groups. These modifying groups are bonded, alone or in combination of two or more, to (introduced into) the ionic groups of cellulose fibers having ionic groups. Examples of bonding modes between the modifying group and the ionic group include ionic bonds and / or covalent bonds. Examples of covalent bonds include, for example, amide bonds, ester bonds, and carbamate bonds.

[0079] (a) hydrocarbon group

[0080] Examples of hydrocarbon groups include monovalent hydrocarbon groups, such as chain saturated hydrocarbon groups, chain unsaturated hydrocarbon groups, cyclic saturated hydrocarbon groups, and (heterocyclic) aromatic hydrocarbon groups.

[0081] The hydrocarbon group has 1 or more carbon atoms, preferably 3 or more, more preferably 8 or more, and even more preferably 10 or more. On the other hand, it is preferably 30 or less, more preferably 22 or less, and even more preferably 18 or less. The hydrocarbon group may have the following substituents, and a portion of the hydrocarbon group may be replaced by a hydrogen nitride group.

[0082] Specific examples of chain-type saturated hydrocarbon groups include: methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, isobutyl, pentyl, tert-pentyl, isopentyl, hexyl, isohexyl, heptyl, octyl, 2-ethylhexyl, nonyl, decyl, dodecyl, tridecyl, trioctyl, tetradecyl, octadecyl, dodecyl, octadecyl, dodecyl, octadecyl, etc.

[0083] Specific examples of chain-type unsaturated hydrocarbon groups include: ethylene, propylene, butenyl, isobutenyl, isoprenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, dodecenyl, tridecenyl, tetradecenyl, and octadecenyl.

[0084] Specific examples of cyclic saturated hydrocarbon groups include: cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, cyclododecyl, cyclotridecyl, cyclotetradecyl, cyclooctadecyl, etc.

[0085] As an aromatic hydrocarbon group, it is selected from aryl and aralkyl groups, for example.

[0086] Examples of aryl groups include: phenyl, naphthyl, anthracene, phenanthryl, biphenyl, triphenyl, bitriphenyl, and groups substituted with the following substituents.

[0087] Examples of aralkyl groups include benzyl, dibenzyl, triphenylmethyl, phenethyl, phenylpropyl, phenylpentyl, phenylhexyl, phenylheptyl, phenyloctyl, and alkyl groups in which the aromatic groups of these groups are further substituted with substituents.

[0088] (b) Polymer base

[0089] The polymer group is a functional group containing a polymer structure. From the viewpoint of improving dispersion stability, the molecular weight of the polymer group is preferably 100 or more, more preferably 200 or more, more preferably 300 or more, more preferably 400 or more, even more preferably 600 or more, even more preferably 1,000 or more, and even more preferably 1,500 or more. Similarly, it is preferably 10,000 or less, more preferably 7,000 or less, even more preferably 5,000 or less, even more preferably 4,000 or less, even more preferably 3,500 or less, and even more preferably 2,500 or less.

[0090] From the viewpoint of improving dispersion stability, the polymer base preferably has functional groups with repeating structures connected by oxygen atoms, more preferably functional groups with repeating structures connected by oxygen atoms such as polyoxyalkylene structures (epoxyalkylene chains) and polysiloxane structures (silicone chains), even more preferably functional groups with polyoxyalkylene structures, and even more preferably alkoxy polyoxyalkylene structures.

[0091] (b-1) Polysiloxane structure (silicone chain)

[0092] Polysiloxane structures (silicone chains) are structures with siloxane bonds as the main chain, which may further include alkylene groups. Polysiloxane structures may have the following substituents.

[0093] (b-2) Polyoxyalkylene structure (epoxide chain)

[0094] From the viewpoint of improving dispersion stability, the polyoxyalkylene structure (epoxide chain) is preferably a (co)polymer structure selected from one or more oxyalkylene groups having 2 or more and 8 or fewer carbon atoms, more preferably a (co)polymer structure selected from one or more oxyalkylene groups having 2 or more and 4 or fewer carbon atoms, even more preferably a (co)polymer structure selected from one or two oxyalkylene groups selected from ethylene oxide (EO) and propylene oxide (PO), and even more preferably a copolymer structure formed by random or block polymerization of ethylene oxide (EO) and propylene oxide (PO) (also known as (EO / PO) structure).

[0095] As a polyoxyalkylene structure, for example, the following formula can be cited:

[0096] [Chemical Formula 1]

[0097]

[0098] (where R is in the formula) 1 This represents a hydrogen atom, a hydrocarbon group with 1 or more carbon atoms but less than 6 carbon atoms, or a -CH2CH(CH3)NH2 group. EO and PO exist randomly or in block form. 'a' represents 0 or a positive number indicating the average number of moles added to EO, and 'b' represents 0 or a positive number indicating the average number of moles added to PO. (Note that 'a' and 'b' are not both 0).

[0099] In R 1 When the alkyl group is a straight-chain or branched alkyl group having 1 or more but 6 or fewer carbon atoms, the alkyl group is preferably methyl, ethyl, n-propyl, or sec-propyl. 1 It can also be a hydrogen atom.

[0100] From the viewpoint of improving dispersion stability, α is preferably 0 or more, more preferably 1 or more, even more preferably 3 or more, even more preferably 6 or more, even more preferably 11 or more, even more preferably 15 or more, even more preferably 20 or more, even more preferably 25 or more, even more preferably 30 or more. From the same viewpoint, α is preferably 100 or less, more preferably 70 or less, even more preferably 60 or less, even more preferably 50 or less, even more preferably 40 or less.

[0101] From the viewpoint of improving dispersion stability, b is preferably 0 or more, more preferably 1 or more, further preferably 3 or more, and even more preferably 5 or more. Similarly, from the viewpoint of improving dispersion stability, b is preferably 50 or less, more preferably 40 or less, further preferably 30 or less, further preferably 25 or less, further preferably 20 or less, further preferably 15 or less, and even more preferably 10 or less.

[0102] In the above formula, a+b represents the total average number of moles added to EO and PO, preferably 4 or more, more preferably 6 or more, more preferably 8 or more, and by the same opinion, preferably 100 or less, more preferably 70 or less.

[0103] Examples of alkylene groups having 1 to 3 carbon atoms include methylene, ethylene, and propylene.

[0104] The PO content (mol%) in the (EO / PO) chain can be calculated based on a and b above, specifically, it can be obtained by b × 100 / (a ​​+ b). From the viewpoint of further improving dispersibility, the PO content is preferably 1 mol% or more, more preferably 5 mol% or more, even more preferably 7 mol% or more, and even more preferably 10 mol% or more. Similarly, it is preferably 100 mol% or less, more preferably 90 mol% or less, even more preferably 85 mol% or less, even more preferably 75 mol% or less, even more preferably 60 mol% or less, even more preferably 50 mol% or less, even more preferably 40 mol% or less, and even more preferably 30 mol% or less.

[0105] From the viewpoint of improving dispersion stability, the molecular weight (molecular weight) of the polyoxyalkylene structure is preferably 100 or more, more preferably 200 or more, even more preferably 300 or more, even more preferably 500 or more, even more preferably 1,000 or more, and even more preferably 1,500 or more. Similarly, it is preferably 10,000 or less, more preferably 7,000 or less, even more preferably 5,000 or less, even more preferably 4,000 or less, even more preferably 3,500 or less, and even more preferably 2,500 or less.

[0106] (c) Further substituents

[0107] It should be noted that the modifying group may be further substituented. Examples of substituents include: alkoxy groups with 1 to 6 carbon atoms, such as methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, sec-butoxy, tert-butoxy, pentoxy, isopentoxy, and hexoxy; alkoxycarbonyl groups with 1 to 6 carbon atoms, such as methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl, butoxycarbonyl, isobutoxycarbonyl, sec-butoxycarbonyl, tert-butoxycarbonyl, pentoxycarbonyl, and isopentoxycarbonyl; halogen atoms, such as fluorine, chlorine, bromine, and iodine; acyl groups with 1 to 6 carbon atoms, such as acetyl and propionyl; aralkyl groups; aralkyloxy groups; alkylamino groups with 1 to 6 carbon atoms; dialkylamino groups with 1 to 6 carbon atoms of alkyl groups; and hydroxyl groups.

[0108] [Methods for bonding modifying groups other than silanol groups]

[0109] Step 1 can be carried out by mixing cellulose fibers having ionic groups and the aforementioned compound having a modifying group other than a silanol group (hereinafter referred to as the "modifying compound"), and reacting the two. As a specific method for Step 1, a known method can be used, such as the method described in Japanese Patent Application Publication No. 2015-143336. According to this method, the modifying group and the ionic group are bonded by ionic bonds. Alternatively, Step 1 can also be carried out, for example, by the method described in Japanese Patent Application Publication No. 2015-143337. In this case, the modifying group and the ionic group are bonded by amide bonds.

[0110] (Compounds for modification)

[0111] From the perspective of improving dispersion stability, compounds for modification can be described as compounds having modification groups other than silanol groups and that can bond with cellulose fibers having ionic groups.

[0112] When using TEMPO-oxidized cellulose fibers as cellulose fibers with ionic groups, compounds having both a modifying group and a cationic group are preferred as modifying compounds, and compounds having both a modifying group and an amino or quaternary ammonium group are even more preferred. As preferred examples of modifying compounds, from the viewpoint of improving dispersion stability, amine compounds having a modifying group and at least one amino group within the molecule are preferred; more specifically, amine compounds having a hydrocarbon group, amine compounds having a polysiloxane structure, or amine compounds having a polyoxyalkylene structure are preferred.

[0113] The amine compound can be any of the primary, secondary, tertiary, and quaternary ammonium compounds. From a reactivity point of view, the following are preferred anionic components of the quaternary ammonium compound: halide ions such as chloride or bromide ions, hydrogen sulfate ions, perchlorate ions, tetrafluoroborate ions, hexafluorophosphate ions, trifluoromethanesulfonate ions, and hydroxide ions.

[0114] (a) Amine compounds with hydrocarbon groups

[0115] Specific examples of amine compounds having a hydrocarbon group, such as primary, secondary, and tertiary amines, include: ethylamine, diethylamine, triethylamine, propylamine, dipropylamine, butylamine, dibutylamine, hexylamine, 2-ethylhexylamine, dihexylamine, trihexylamine, octylamine, dioctylamine, trioctylamine, dodecylamine, di(dodecyl)amine, stearylamine, distearate, monoethanolamine, diethanolamine, triethanolamine, oleylamine, aniline, octadecylamine, dimethylbenzylamine, benzylamine, dibenzylamine, triphenylmethylamine, naphthylamine, imidazole, 2-methylimidazolium, 2-ethylimidazolium, 2-phenylimidazolium, 2-ethyl-4-methylimidazolium, 2-phenyl-4-methylimidazolium, 1-(3-aminopropyl)imidazolium, etc.

[0116] Examples of quaternary ammonium compounds include: tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetraethylammonium chloride, tetrapropylammonium hydroxide (TPAH), tetrabutylammonium hydroxide (TBAH), tetrabutylammonium chloride, lauryltrimethylammonium chloride, dilauryldimethylammonium chloride, stearyltrimethylammonium chloride, distearyldimethylammonium chloride, cetyltrimethylammonium chloride, and alkylbenzyldimethylammonium chloride.

[0117] Amine compounds with hydrocarbon groups can be commercially available or prepared using known methods.

[0118] It should be noted that hydrocarbon compounds with cationic groups may have substituents. Specific examples of substituents can be found in "(c) Further Substituents" above.

[0119] (b-1) Amine compounds with a polysiloxane structure

[0120] Examples of amine compounds include those having a backbone of a polysiloxane structure with an amino group bonded to it via an alkylene group. In this specification, the amine compound is sometimes referred to as an "amino-modified silicone." Amino-modified silicones can be commercially available or prepared using known methods. Only one type of amino-modified silicone may be used, or two or more types may be used.

[0121] In terms of performance, the preferred amino-modified silicones are: TSF4703 (kinematic viscosity: 1000, amino equivalent: 1600), TSF4708 (kinematic viscosity: 1000, amino equivalent: 2800) manufactured by Momentive Advanced Materials Co., Ltd.; SS-3551 (kinematic viscosity: 1000, amino equivalent: 1600) manufactured by Dow Corning Toray Silicone Co., Ltd.; SF8457C (kinematic viscosity: 1200, amino equivalent: 1800); SF8417 (kinematic viscosity: 1200, amino equivalent: 1700); BY16-209 (kinematic viscosity: 500, amino equivalent: 1800); BY16-892 (kinematic viscosity: 1500, amino equivalent: 2000); and BY16-898 (kinematic viscosity: 2000, amino equivalent: 2800). 900), FZ-3760 (kinematic viscosity: 220, amino equivalent: 1600), KF8002 (kinematic viscosity: 1100, amino equivalent: 1700) manufactured by Shin-Etsu Chemical Industry Co., Ltd., KF867 (kinematic viscosity: 1300, amino equivalent: 1700), KF-864 (kinematic viscosity: 1700, amino equivalent: 3800), BY16-213 (kinematic viscosity: 55, amino equivalent: 2700), BY16-853U (kinematic viscosity: 14, amino equivalent: 450). Within ( ), kinematic viscosity represents the measured value at 25°C (unit: mm). 2 / s), the unit of amino equivalent is g / mol.

[0122] (b-2) Amine compounds with polyoxyalkylene structures

[0123] The polyoxyalkylene structure in the amine compound is preferably bonded directly or via a linker to the nitrogen atom of the amine compound. As the linker, a hydrocarbon group is preferred, and examples include alkylene groups with 1 or more carbon atoms and 6 or less, more preferably 1 or more carbon atoms and 3 or less. Examples of such alkylene groups are ethylene and propylene.

[0124] Examples of amine compounds having a polyoxyalkylene structure include those represented by formula (i):

[0125] [Chemical Formula 2]

[0126]

[0127] R in equation (i) 1 a and b, and R in the formula representing an example of the above polyoxyalkylene structure. 1 a and b are the same.

[0128] Amine compounds having a polyoxyalkylene structure are compounds used to introduce the modifying group represented by the aforementioned polyoxyalkylene structure, and can be prepared according to known methods. For example, after adding the required amount of ethylene oxide or propylene oxide to a propylene glycol alkyl ether, the hydroxyl terminus is aminated. If necessary, the alkyl ether can be cleaved by acid to make the terminus a hydrogen atom. These manufacturing methods can be found in Japanese Patent Application Publication No. 3-181448, and details of the amine compound are described, for example, in Japanese Patent Application Publication No. 6105139.

[0129] Amine compounds having a polyoxyalkylene structure may be suitable for use, for example, in commercially available products.

[0130] Specific examples of amine compounds that contain the aforementioned EO or PO chains and may have hydrocarbon groups include: SUNBRIGHT MEPA-10H, SUNBRIGHT MEPA-20H, SUNBRIGHT MEPA-50H, SUNBRIGHT MEPA-10T, SUNBRIGHT MEPA-12T, SUNBRIGHT MEPA-20T, SUNBRIGHT MEPA-30T, and SUNBRIGHT MEPA-40T manufactured by Nippon Oil Co., Ltd.

[0131] Specific examples of amine compounds that contain the aforementioned EO / PO chains and may have hydrocarbon groups include: Jeffamine M-2070, Jeffamine M-2005, Jeffamine M-2095, Jeffamine M-1000, Jeffamine M-600, Surfoamine B200, Surfoamine L100, Surfoamine L200, Surfoamine L207, Surfoamine L300, Surfoamine B-100, XTJ-501, XTJ-506, XTJ-507, XTJ-508, M3000, Jeffamine ED-600, Jeffamine ED-900, Jeffamine ED-2003, Jeffamine D-230, Jeffamine D-400, Jeffamine D-2000, and Jeffamine D-2000 manufactured by HUNTSMAN. D-4000, XTJ-510, Jeffamine T-3000, Jeffamine T-5000, XTJ-502, XTJ-509, XTJ-510, etc. These can be used individually or in combination of two or more.

[0132] (Mixed conditions)

[0133] From the viewpoint of reactivity, the mixing temperature, i.e., the reaction temperature, is less than 25°C, preferably less than 20°C, and more preferably less than 10°C. Furthermore, from the viewpoint of product yield, the temperature is preferably -20°C or higher, more preferably -10°C or higher, and more preferably -5°C or higher.

[0134] The mixing time is preferably 0.1 hours or more, more preferably 0.5 hours or more, even more preferably 1 hour or more, and from a productive point of view, preferably 120 hours or less, more preferably 72 hours or less, even more preferably 48 hours or less, and even more preferably 24 hours or less.

[0135] A solvent may be used during mixing in step 1. Preferably, a solvent that dissolves the compound being used is selected, such as methanol, ethanol, isopropanol (IPA), N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N,N-dimethylacetamide, tetrahydrofuran (THF), acetone, methyl ethyl ketone (MEK), cyclohexanone, ethyl acetate, acetonitrile, dichloromethane, chloroform, toluene, acetic acid, 1-methoxy-2-propanol (PGME), water, etc. One of these may be used alone, or two or more may be used in combination.

[0136] Furthermore, in order to make the components in step 1 more evenly dispersed, a high-pressure homogenizer or similar device can be used for dispersion treatment after mixing is completed.

[0137] A condensing agent may be used during mixing in step 1. By using a condensing agent, the modifying group can be bonded to the ionic group via an amide bond. There are no particular limitations on the condensing agent, but examples include: the condensing agents described in the Synthetic Chemistry Series Peptide Synthesis (Maruzen Co., Ltd.) P116; or the condensing agents described in Tetrahedron, 57, 1551, (2001), such as 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholine hydrochloride.

[0138] (Amount of modifying compound used)

[0139] The amount of the modifying compound used in step 1 is preferably within the following range, for example.

[0140] That is, the range of the amount used can be expressed as the range of the equivalent amount of the functional group of the modifying compound (which can react with the ionic group) relative to the ionic group of the cellulose fiber having the ionic group. Specifically, from the viewpoint of improving dispersion stability, it is preferably 0.10 equivalents or more, more preferably 0.15 equivalents or more, and even more preferably 0.2 equivalents or more. In addition, from the viewpoint of film-forming properties, it is preferably 20 equivalents or less, more preferably 5 equivalents or less, even more preferably 1 equivalent or less, and even more preferably 0.7 equivalents or less.

[0141] [Cellulose fibers with bonded modification groups]

[0142] The main properties of the cellulose fibers with bonded modification groups obtained in step 1 are described below.

[0143] (Average fiber diameter)

[0144] Cellulose fibers bonded with modifying groups are preferably micronized to achieve nanoscale dimensions. Therefore, from the viewpoints of processability, availability, and cost, the average fiber diameter of the cellulose fibers bonded with modifying groups is preferably 1 nm or more, more preferably 2 nm or more, and from the viewpoints of improving processability and dispersibility, preferably 300 nm or less, more preferably 200 nm or less, further preferably 150 nm or less, and even more preferably 120 nm or less.

[0145] (Average fiber length)

[0146] From the viewpoint of the strength performance of the cured resin, the average fiber length of the cellulose fibers bonded with the modified groups is preferably 10 nm or more, more preferably 30 nm or more, and even more preferably 50 nm or more. On the other hand, from the viewpoint of sprayability and processability, it is preferably 1000 nm or less, more preferably 500 nm or less, and even more preferably 300 nm or less.

[0147] The average fiber diameter and average fiber length of the cellulose fibers bonded with the modification groups were determined by the methods described in the following examples.

[0148] (Bonding amount and introduction rate of modifying groups)

[0149] From the viewpoint of affinity with resin components, the amount of modified groups bonded in the cellulose fibers with the modified groups is preferably 0.01 mmol / g or more, and more preferably 3.0 mmol / g or less. When any two or more modified groups are simultaneously introduced into the cellulose fibers, the total amount of modified groups bonded is preferably within the above range.

[0150] From the viewpoint of dispersibility, the introduction rate of the modifying group in the cellulose fiber bonded with the modifying group is preferably 10 mol% or more, the higher the better, and preferably 100 mol%. When any two or more modifying groups are introduced simultaneously, the total introduction rate is preferably within the range of 100 mol%, which is within the range mentioned above.

[0151] The amount of modification group bonded and the introduction rate can be adjusted by the type or amount of the modifying compound, reaction temperature, reaction time, and type of solvent. The amount of modification group bonded (mmol / g) and the introduction rate (mol%) are the amount and proportion of the modification group introduced onto the ionic group in the cellulose fiber bonded with the modification group. For example, when the ionic group is a carboxyl group, the amount of modification group bonded and the introduction rate in the cellulose fiber bonded with the modification group are calculated by the method described in the following examples.

[0152] [Process 2]

[0153] Step 2 in this invention comprises the following steps: mixing the cellulose fibers with the modified groups obtained in step 1 with a specific silane compound, namely, one or more silane compounds selected from chlorosilane compounds, alkoxysilane compounds, acetoxysilane compounds and silanol compounds.

[0154] It is presumed that through mixing, at least a portion of the functional groups of the silane compound are converted into silanol groups, at least a portion of which react with at least a portion of the hydroxyl groups of the cellulose fiber bonded with the modified group, thereby bonding the silane compound to the cellulose fiber bonded with the modified group.

[0155] [Silane compounds]

[0156] The silane compound used in this process is one or more silane compounds selected from chlorosilane compounds, alkoxysilane compounds, acetoxysilane compounds, and silanol compounds.Specifically, examples include: tetrachlorosilane, methyltrichlorosilane, phenyltrichlorosilane, dimethyldichlorosilane, diphenyldichlorosilane, methylvinyldichlorosilane, trimethylchlorosilane, methyldiphenylchlorosilane, and other chlorosilane compounds; tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, tetrabutoxysilane, methyltrimethoxysilane, methyltriethoxysilane, octyltrimethoxysilane, decyltrimethoxysilane, hexadecyltrimethoxysilane, polyethylene glycol-modified alkoxysilane, trimethoxyvinylsilane, triethoxyvinylsilane, 7-octenyltrimethoxysilane, n-propyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, [8-(glycidoxypropyltrimethoxysilane)]... [Oxyl]trimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-chloropropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-(2-aminoethylamino)propyltrimethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, p-styryltrimethoxysilane, 3-methacryloyloxypropylmethyldimethoxysilane, 3-methacryloyloxypropylmethyldiethoxysilane, 3-methacryloyloxypropylmethyldiethoxysilane, 3-methacryloyloxypropyltriethoxysilane, 8-methacryloyloxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-... Glyceryl oxypropylmethyl diethoxysilane, 3-chloropropylmethyldimethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, dimethoxydiethoxysilane, trimethylmethoxysilane, trimethylethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldimethoxymethylsilane, 3-aminopropyldiethoxymethylsilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropyltriethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-8-aminooctyltrimethoxysilane, [3-(methylamino)propyl]trimethoxy Alkoxysilane compounds such as silanes, [3-(butylamino)propyl]trimethoxysilane, N-[3-(trimethoxysilyl)propyl]hexamethylenediamine, 3-triethoxysilyl-N-(1,3-dimethyl-butylene)propylamine, N,N-dimethyl-3-(trimethoxysilyl)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, 3-ureopropyltriethoxysilane, and 3-ureopropyltrialkoxysilane; acetoxysilane compounds such as tetraacetoxysilane, methyltriacetoxysilane, phenyltriacetoxysilane, dimethyldiacetoxysilane, diphenyldiacetoxysilane, and trimethylacetoxysilane; and silanol compounds such as dimethylsilanediol, diphenylsilanediol, and trimethylsilanol.Of the silane compounds exemplified above, alkoxysilane compounds are preferred from the viewpoints of availability and reactivity.

[0157] More preferred examples of this silane compound include, for example, 3-aminopropyltrimethoxysilane, n-propyltrimethoxysilane, and N-phenyl-3-aminopropyltrimethoxysilane.

[0158] [Mixed conditions]

[0159] From the viewpoint of suppressing the condensation reaction between silane compounds, the mixing temperature, i.e., the reaction temperature, is preferably 70°C or lower, more preferably 50°C or lower, and even more preferably 30°C or lower. Furthermore, from the viewpoint of the yield of modified cellulose fibers, the temperature is preferably -20°C or higher, more preferably -10°C or higher, and more preferably -5°C or higher.

[0160] The mixing time is preferably 0.1 hours or more, more preferably 0.5 hours or more, even more preferably 1 hour or more, and from a productive point of view, preferably 120 hours or less, more preferably 72 hours or less, even more preferably 48 hours or less, and even more preferably 24 hours or less.

[0161] A solvent may be used during mixing in step 2. Preferably, a solvent suitable for dissolving the compound being used is selected, such as methanol, ethanol, isopropanol (IPA), N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N,N-dimethylacetamide, tetrahydrofuran (THF), acetone, methyl ethyl ketone (MEK), cyclohexanone, ethyl acetate, acetonitrile, dichloromethane, chloroform, toluene, acetic acid, 1-methoxy-2-propanol (PGME), water, etc. One of these may be used alone, or two or more may be used in combination.

[0162] Furthermore, in order to make the components in step 2 more evenly dispersed, a high-pressure homogenizer or similar device can be used for dispersion treatment after mixing is completed.

[0163] (Amount of silane compound)

[0164] The amount of silane compound in step 2 is 50 parts by mass or more, relative to 100 parts by mass of cellulose fibers bonded with the modifying group. Here, the mass of the cellulose fibers bonded with the modifying group is defined as the mass of the cellulose fiber portion only in the cellulose fibers bonded with the modifying group, that is, the mass of the cellulose fiber portion from which the modifying group has been removed.

[0165] From the viewpoint of improving the heat resistance of the resin when incorporated into the resin, the amount of silane compound incorporated is preferably 60 parts by mass or more, more preferably 70 parts by mass or more, and even more preferably 80 parts by mass or more. On the other hand, from the viewpoint of cost, the amount of silane compound incorporated is preferably 1000 parts by mass or less, more preferably 800 parts by mass or less, and even more preferably 500 parts by mass or less.

[0166] [Miniaturization process]

[0167] By micronizing cellulose fibers at any stage of the manufacturing method of the present invention, micron-scale cellulose fibers can be micronized to nanoscale. This is preferred because reducing the average fiber diameter to the nanoscale improves dispersibility in the resin.

[0168] The micronization process can employ well-known micronization methods. For example, in obtaining modified cellulose fibers with an average fiber diameter of nanometers, processing methods using a grinding mill such as a microparticle mill or a high-pressure homogenizer in a medium can be implemented.

[0169] Specific examples of devices used in media or miniaturization processes are described in paragraphs 0079 to 0080 of Japanese Patent Application Publication No. 2022-001634.

[0170] [Short fiber treatment]

[0171] In any stage of the manufacturing method of the present invention, a shortening treatment of the cellulose fibers may be further performed, that is, a treatment to shorten the fiber length. The shortening treatment can be achieved by subjecting the cellulose fibers to a known treatment, such as one or more treatment methods selected from alkali treatment, acid treatment, heat treatment, ultraviolet treatment, electron beam treatment, mechanical treatment, and enzyme treatment.

[0172] B. Method for manufacturing modified cellulose fibers including steps 3 and 4

[0173] A further embodiment of the method for manufacturing modified cellulose fibers of the present invention is a method for manufacturing modified cellulose fibers, which includes the following steps:

[0174] Step 3: A step of mixing cellulose fibers with ionic groups with one or more silane compounds selected from chlorosilane compounds, alkoxysilane compounds, acetoxysilane compounds, and silanol compounds to obtain cellulose fibers bonded with silane compounds; and

[0175] Step 4: A step of bonding modifying groups other than silanol groups to the ionic groups of the cellulose fibers bonded with silane compounds, thereby obtaining modified cellulose fibers; and

[0176] The amount of the silane compound in step 3 is 50 parts by mass or more, relative to 100 parts by mass of the cellulose fiber portion of the cellulose fiber with ionic groups.

[0177] [Process 3]

[0178] Step 3 in this invention is the following step: mixing cellulose fibers with ionic groups with the above-mentioned specific silane compound to obtain cellulose fibers bonded with the silane compound.

[0179] It is presumed that through mixing, at least a portion of the functional groups of the silane compound are converted into silanol groups, and at least a portion of these silanol groups react with at least a portion of the hydroxyl groups of the cellulose fibers having ionic groups, thereby bonding the cellulose fibers to the silane compound. Furthermore, it is presumed that the ionic groups in the cellulose fibers having ionic groups do not react with the silanol groups.

[0180] [Cellulose fibers with ionic groups]

[0181] The main properties of the "cellulose fibers with ionic groups" supplied to process 3 are the same as those in method A above.

[0182] [Preparation of cellulose fibers with ionic groups]

[0183] The preparation method of the "cellulose fiber with ionic groups" supplied to step 3 is the same as the preparation method in method A above.

[0184] [Silane compounds]

[0185] The "silane compound" supplied in step 3 is the same as the silane compound in method A above.

[0186] [Mixed conditions]

[0187] The mixing temperature, mixing time, and solvents used during mixing are the same as those in step 2 above. Furthermore, in order to make the components in step 3 more uniformly dispersed, a dispersion treatment such as a high-pressure homogenizer can be performed after mixing.

[0188] (Amount of silane compound)

[0189] The amount of silane compound in step 3 is 50 parts by mass or more, relative to 100 parts by mass of cellulose fibers with ionic groups. Here, the mass of cellulose fibers with ionic groups is defined as the mass of the cellulose fiber portion only in the cellulose fibers with ionic groups, that is, the mass of the cellulose fiber portion from which the ionic groups have been removed.

[0190] From the viewpoint of improving the heat resistance of the resin when incorporated into the resin, the amount of silane compound incorporated is preferably 60 parts by mass or more, more preferably 70 parts by mass or more, and even more preferably 80 parts by mass or more. On the other hand, from the viewpoint of cost, the amount of silane compound incorporated is preferably 1000 parts by mass or less, more preferably 800 parts by mass or less, and even more preferably 500 parts by mass or less.

[0191] Cellulose fibers bonded with silane compounds

[0192] The main properties of the cellulose fibers bonded with silane compounds obtained in step 3, such as the average fiber diameter and average fiber length, are the same as those of the "cellulose fibers bonded with modified groups" obtained in step 1 above.

[0193] [Process 4]

[0194] Step 4 is the following step: bonding a modification group other than a silanol group to the ionic group of the cellulose fiber bonded with the silane compound, thereby obtaining modified cellulose fiber.

[0195] The "modifying groups other than silanol groups" introduced in step 4 are the same as the modifying groups other than silanol groups in method A above.

[0196] The "method for bonding modification groups other than silanol groups" in step 4, or the "modification compound" or "amount used", the "mixing conditions" during bonding, and the "bonding amount and introduction rate of modification groups" are the same as those in method A above.

[0197] In any stage of the manufacturing method of this method, the cellulose fibers can be micronized and / or shortened in the same manner as in Method A above.

[0198] C. Modified cellulose fibers manufactured by the manufacturing method described in method A or method B above.

[0199] Method C of the present invention is a modified cellulose fiber, which is manufactured by the manufacturing method of Method A or Method B described above.

[0200] As described above, modified cellulose fibers can be obtained by a manufacturing method including steps 1 and 2, or by a manufacturing method including steps 3 and 4. At least a portion of the modified cellulose fibers is bonded to the silane compound.

[0201] It is presumed that through the mixing in step 2 or step 3, at least a portion of the functional groups of the silane compound is converted into silanol groups, and at least a portion of the silanol groups react with at least a portion of the hydroxyl groups of the cellulose fiber bonded with the modifying group or at least a portion of the hydroxyl groups of the cellulose fiber having an ionic group, thereby bonding the cellulose fiber to the silane compound. Therefore, the modified cellulose fiber manufactured by the manufacturing method of method A or method B has modifying groups and groups derived from the silane compound.

[0202] The preferred contents of each component in the modified cellulose fiber of the present invention are as follows.

[0203] As for the content of cellulose fibers, that is, the amount of cellulose fiber portion other than the bonded modifying groups and the bonded silane compounds, from the viewpoint of improving the heat resistance of the resin, it is preferably 5% by mass or more, more preferably 10% by mass or more, and even more preferably 15% by mass or more. On the other hand, from the same viewpoint, it is preferably 90% by mass or less, more preferably 80% by mass or less, and even more preferably 70% by mass or less.

[0204] From the viewpoint of improving the heat resistance of the resin, the content of silane compounds is preferably 1% by mass or more, more preferably 5% by mass or more, and even more preferably 10% by mass or more. On the other hand, from the same viewpoint, it is preferably 80% by mass or less, more preferably 70% by mass or less, and even more preferably 60% by mass or less.

[0205] From the viewpoint of improving the heat resistance of the resin, the content of the modifying group is preferably 0.1% by mass or more, more preferably 1% by mass or more, and even more preferably 5% by mass or more. On the other hand, from the same viewpoint, it is preferably 80% by mass or less, more preferably 70% by mass or less, and even more preferably 60% by mass or less.

[0206] It should be noted that the content of each component can be calculated based on the proportions of each component.

[0207] D. Compositions containing modified cellulose fibers

[0208] Embodiment D of the present invention is a composition containing modified cellulose fibers. The composition of the present invention comprises modified cellulose fibers and may further comprise an organic solvent and / or a resin.

[0209] [Organic solvents]

[0210] As organic solvents, it is preferable to choose solvents that can dissolve modified cellulose fibers or the aforementioned silane compounds, such as methanol, ethanol, isopropanol (IPA), N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N,N-dimethylacetamide, tetrahydrofuran (THF), acetone, methyl ethyl ketone (MEK), cyclohexanone, ethyl acetate, acetonitrile, dichloromethane, chloroform, toluene, acetic acid, 1-methoxy-2-propanol (PGME), etc., and these can be used alone or in combination of two or more.

[0211] The preferred amounts of each component in the composition of the present invention when it contains an organic solvent are as follows.

[0212] The content of cellulose fibers in the composition of the present invention, that is, the amount of cellulose fiber portion other than the bonded modifying groups and the bonded silane compounds, is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1% by mass or more, from the viewpoint of improving the heat resistance of the resin. On the other hand, from the same viewpoint, it is preferably 20% by mass or less, more preferably 10% by mass or less, and even more preferably 5% by mass or less.

[0213] The content of silane compounds in the composition of the present invention, that is, the total amount of silane compounds bonded to the modified cellulose fibers and silane compounds not bonded to the modified cellulose fibers, is preferably 0.03% by mass or more, more preferably 0.15% by mass or more, and even more preferably 0.3% by mass or more, from the viewpoint of improving the heat resistance of the resin. On the other hand, from the same viewpoint, it is preferably 40% by mass or less, more preferably 20% by mass or less, and even more preferably 10% by mass or less.

[0214] From the viewpoint of improving the heat resistance of the resin, the content of the modifying group in the composition of the present invention is preferably 0.02% by mass or more, more preferably 0.1% by mass or more, and even more preferably 0.2% by mass or more. On the other hand, from the same viewpoint, it is preferably 70% by mass or less, more preferably 35% by mass or less, and even more preferably 20% by mass or less.

[0215] The content of organic solvent in the composition of the present invention is preferably 1% by mass or more, more preferably 5% by mass or more, and even more preferably 10% by mass or more. On the other hand, it is preferably 95% by mass or less, more preferably 90% by mass or less, even more preferably 80% by mass or less, even more preferably 60% by mass or less, and even more preferably 40% by mass or less.

[0216] It should be noted that the content of each component can be calculated based on the proportions of each component.

[0217] [Resin]

[0218] Examples of resins include those described in Method F below. The compositions of the present invention may optionally include a curing agent and a curing accelerator, as needed.

[0219] From the viewpoint of improving the heat resistance of resin, the content or amount of modified cellulose fiber in the composition of the present invention, more specifically, is preferably 4.0% by mass or more, more preferably 5.0% by mass or more, and even more preferably 6.0% by mass or more. On the other hand, from the same viewpoint, it is preferably 20% by mass or less, more preferably 15% by mass or less, and even more preferably 10% by mass or less.

[0220] The preferred amounts or proportions of each component in the composition of the present invention, when containing organic solvents and resins, are as follows.

[0221] More specifically, the content or amount of cellulose fibers in the resin composition of the present invention, that is, the amount of cellulose fiber portion other than the bonded modifying groups and the bonded silane compounds, is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1% by mass or more, from the viewpoint of improving the heat resistance of the resin. On the other hand, from the same viewpoint, it is preferably 20% by mass or less, more preferably 10% by mass or less, and even more preferably 5% by mass or less.

[0222] More specifically, the content or amount of silane compound in the resin composition of the present invention, that is, the total amount of silane compound bonded to the modified cellulose fiber and silane compound not bonded to the modified cellulose fiber, is preferably 0.03% by mass or more, more preferably 0.15% by mass or more, and even more preferably 0.3% by mass or more, from the viewpoint of improving the heat resistance of the resin. On the other hand, from the same viewpoint, it is preferably 40% by mass or less, more preferably 20% by mass or less, and even more preferably 10% by mass or less.

[0223] As a composition of the present invention, more specifically, the content or amount of modifying group in the resin composition of the present invention, from the viewpoint of improving the heat resistance of the resin, is preferably 0.02% by mass or more, more preferably 0.1% by mass or more, and even more preferably 0.2% by mass or more. On the other hand, from the same viewpoint, it is preferably 70% by mass or less, more preferably 35% by mass or less, and even more preferably 20% by mass or less.

[0224] More specifically, the content or amount of organic solvent in the resin composition of the present invention is preferably 1% by mass or more, more preferably 5% by mass or more, and even more preferably 10% by mass or more. On the other hand, it is preferably 49% by mass or less, more preferably 45% by mass or less, and even more preferably 40% by mass or less.

[0225] More specifically, the resin content or amount in the resin composition of the present invention is preferably 70% by mass or more, more preferably 75% by mass or more, and even more preferably 80% by mass or more, from the viewpoint of improving resin moldability. On the other hand, from the viewpoint of improving resin heat resistance, it is preferably 95% by mass or less, more preferably 94% by mass or less, and even more preferably 93% by mass or less.

[0226] It should be noted that the content of each component can be calculated based on the proportions of each component.

[0227] From the viewpoint of improving the heat resistance of the resin, in the composition of the present invention, more specifically, the mass ratio of the amount of modified cellulose fiber in the resin composition to the amount of resin (amount of modified cellulose fiber / amount of resin) is preferably 5 / 95 or more, more preferably 6 / 94 or more, and even more preferably 7 / 93 or more. On the other hand, from the same viewpoint, it is preferably 20 / 80 or less, more preferably 15 / 85 or less, and even more preferably 10 / 90 or less.

[0228] From the viewpoint of improving the heat resistance of the resin, in the composition of the present invention, more specifically, the mass ratio of the amount of cellulose fiber in the resin composition to the amount of resin (amount of cellulose fiber / amount of resin) is preferably 0.1 / 99.9 or more, more preferably 0.5 / 99.5 or more, and even more preferably 1 / 99 or more. On the other hand, from the same viewpoint, it is preferably 20 / 80 or less, more preferably 10 / 90 or less, and even more preferably 5 / 95 or less. Here, the above-mentioned amount of cellulose fiber refers to the amount of cellulose fiber portion other than the bonded modifying group and the bonded silane compound.

[0229] [Other ingredients]

[0230] Within the scope of not impairing the effects of the present invention, the composition may include, for example, plasticizers, crystal nucleating agents, fillers (inorganic fillers, organic fillers), hydrolysis inhibitors, flame retardants, antioxidants, lubricants as hydrocarbon waxes or anionic surfactants, ultraviolet absorbers, antistatic agents, antifogging agents, light stabilizers, pigments, mildew inhibitors, antibacterial agents, foaming agents, surfactants; starches, alginic acid and other polysaccharides; gelatin, animal glue, casein and other natural proteins; tannins, zeolites, ceramics, metal powders and other inorganic compounds; fragrances; flow regulators; leveling agents; conductive agents; ultraviolet dispersants; deodorizers, etc. Furthermore, other polymeric materials and other compositions may be added within the scope of not hindering the effects of the present invention.

[0231] E. Additives for resins containing the modified cellulose fibers described in method C above.

[0232] The resin additive of Method E of the present invention comprises the modified cellulose fiber described in Method C above, and may also comprise an organic solvent.

[0233] By adding the resin additives of the present invention to the resin, the heat resistance and strength of the resin during curing are improved.

[0234] [Organic solvents]

[0235] As an organic solvent, the solvent described in method D above is preferred.

[0236] [composition]

[0237] The preferred amounts of each component in the resin additive of the present invention are the same as those in the composition of the present invention described above when it contains an organic solvent.

[0238] It should be noted that the content of each component can be calculated based on the proportions of each component.

[0239] [Other ingredients]

[0240] Without impairing the effects of the present invention, the resin additives may include, for example, plasticizers, crystal nucleating agents, fillers (inorganic fillers, organic fillers), hydrolysis inhibitors, flame retardants, antioxidants, lubricants as hydrocarbon waxes or anionic surfactants, ultraviolet absorbers, antistatic agents, antifogging agents, light stabilizers, pigments, mildew inhibitors, antibacterial agents, foaming agents, surfactants; starches, alginic acid and other polysaccharides; gelatin, animal glue, casein and other natural proteins; tannins, zeolites, ceramics, metal powders and other inorganic compounds; fragrances; flow regulators; leveling agents; conductive agents; ultraviolet dispersants; deodorizers, etc. Furthermore, without hindering the effects of the present invention, other polymer materials and other compositions may also be added.

[0241] F. Method for manufacturing the resin composition including steps 5 and 6

[0242] One embodiment of the method for manufacturing the resin composition of the present invention is a method for manufacturing a resin composition, which includes the following steps:

[0243] Step 5: A step of bonding a modifying group other than a silanol group to the ionic group of a cellulose fiber, thereby obtaining a cellulose fiber bonded with the modified group; and

[0244] Step 6: A step of mixing one or more silane compounds selected from chlorosilane compounds, alkoxysilane compounds, acetoxysilane compounds, and silanol compounds, the aforementioned cellulose fibers with bonded modification groups, and the resin; and

[0245] The amount of the silane compound in step 6 is 50 parts by mass or more, relative to 100 parts by mass of the cellulose fiber portion of the cellulose fiber bonded with the modified group.

[0246] [Cellulose fibers with ionic groups]

[0247] The main properties of the "cellulose fibers with ionic groups" supplied to process 5 are the same as those in method A above.

[0248] [Preparation of cellulose fibers with ionic groups]

[0249] The preparation method of the "cellulose fiber with ionic group" supplied to step 5 is the same as the preparation method in method A above.

[0250] [Step 5]

[0251] Step 5 in this invention is the same as step 1 in method A above.

[0252] [Step 6]

[0253] Step 6 in this invention comprises the following steps: mixing a specific silane compound, namely, one or more silane compounds selected from chlorosilane compounds, alkoxysilane compounds, acetoxysilane compounds and silanol compounds; the cellulose fibers with the modified groups obtained in step 5; and the resin.

[0254] It is presumed that through mixing, at least a portion of the functional groups of the silane compound are converted into silanol groups, and at least a portion of these silanol groups react with at least a portion of the hydroxyl groups of the cellulose fiber bonded with the modified group, thereby bonding the silane compound to the cellulose fiber bonded with the modified group. Therefore, the modified cellulose fiber obtained through step 6 has the modified group and groups derived from the silane compound.

[0255] [Silane compounds]

[0256] The silane compound used in this process is the same as the silane compound in method A above.

[0257] [Resin]

[0258] The resin used in this process is preferably a curable resin. Examples of curable resins include polyurethane resin, (meth)acrylic resin, epoxy resin, urea resin, melamine resin, and phenolic resin. It is preferred to select one or more of polyurethane resin, (meth)acrylic resin, and epoxy resin.

[0259] When the curing resin is a polyurethane resin, examples of curing monomers include: aromatic monomers such as toluene diisocyanate and diphenylmethane diisocyanate; aliphatic monomers such as hexamethylene diisocyanate, phenyl dimethyl diisocyanate, isophorone diisocyanate, and tetramethylphenyl dimethyl diisocyanate; and polyols such as ethylene glycol, diethylene glycol, butanediol, hexanediol, neopentyl glycol, hydroxyethyl acrylate, trimethylolpropane, dimethylolpropionic acid, and isophorone diamine. The reaction product of isocyanate and polyol becomes a polyurethane resin, but is not limited to this. Oligomers of the listed polyols, or polyols such as polyether polyols, polyester polyols, and polycarbonate polyols, can be used as curing prepolymers.

[0260] When the curing resin is a (meth)acrylate resin, examples of curing monomers include: methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, n-hexyl acrylate, n-hexyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, nonanediol diacrylate, phenoxyethyl acrylate, bisphenol A-epoxyalkylene adduct (meth)acrylates, epoxy (meth)acrylates (bisphenol A type epoxy (meth)acrylates, phenolic varnish type epoxy (meth)acrylates, etc.), polyester (meth)acrylates (e.g., aliphatic polyester type (meth)acrylates, aromatic polyester type (meth)acrylates, etc.), urethane (meth)acrylates (polyester type urethane (meth)acrylates, polyether type urethane (meth)acrylates, etc.), silicone (meth)acrylates, cyanoacrylates, and other (meth)acrylate monoesters. Oligomers of the listed (meth)acrylate monoesters can be used as curing prepolymers.

[0261] When the curing resin is epoxy resin, examples of curing monomers include bisphenol A type, phenolic varnish type, glycidyl ether type, alicyclic type, glycidyl amine type, and glycidyl ester type monomers. Oligomers of the listed monomers can be used as curing prepolymers.

[0262] When the curing resin is a urea resin, urea and formaldehyde can be cited as curing monomers. When the curing resin is a melamine resin, melamine and formaldehyde can be cited as curing monomers. When the curing resin is a phenol resin, phenol, cresol, xylenol, resorcinol, and formaldehyde can be cited as curing monomers.

[0263] [Curing agents and curing accelerators]

[0264] When using thermosetting resins as the resin, curing agents and / or curing accelerators may be used.

[0265] The type of curing agent can be appropriately selected depending on the type of resin. For example, when the resin is epoxy resin, examples of curing agents include: amine-based curing agents, phenolic resin-based curing agents, acid anhydride-based curing agents, polythiol-based curing agents, and latent curing agents (boron trifluoride-amine complex, dicyandiamide, carboxylic acid hydrazide, etc.). Curing agents can be used alone or in combination of two or more. It should be noted that curing agents sometimes also function as curing accelerators.

[0266] The proportion of the curing agent can be appropriately selected according to the type of curing agent, for example, it is preferably 0.1 to 300 parts by weight relative to 100 parts by weight of the resin.

[0267] Curing accelerators can be appropriately selected according to the type of resin. For example, when the resin is epoxy resin, phosphine derivatives and amine derivatives can be used as curing accelerators. Curing accelerators can be used alone or in combination of two or more.

[0268] The proportion of curing accelerator can be appropriately selected according to the type of curing agent, etc. For example, it is preferably 0.01 to 100 parts by weight relative to 100 parts by weight of resin.

[0269] [Mixed conditions]

[0270] The mixing temperature, mixing time, and solvents used during mixing are the same as in step 2. In step 6, the silane compound, the cellulose fibers bonded with the modified groups, and the resin can be mixed simultaneously, or two components can be mixed first, followed by the remaining component. For example, the cellulose fibers bonded with the modified groups and the resin can be mixed first, and then the silane compound can be added to the mixture for further mixing. Furthermore, to ensure more uniform dispersion of the components in step 6, a dispersion treatment such as a high-pressure homogenizer can be performed after mixing.

[0271] (Amount of silane compound)

[0272] The amount of silane compound in step 6 is 50 parts by mass or more, relative to 100 parts by mass of cellulose fibers bonded with the modifying group. Here, the mass of the cellulose fibers bonded with the modifying group is defined as the mass of the cellulose fiber portion only in the cellulose fibers bonded with the modifying group, that is, the mass of the cellulose fiber portion from which the modifying group has been removed.

[0273] From the viewpoint of improving the heat resistance of the resin when incorporated into the resin, the amount of silane compound incorporated is preferably 60 parts by mass or more, more preferably 70 parts by mass or more, and even more preferably 80 parts by mass or more. On the other hand, from the viewpoint of cost, the amount of silane compound incorporated is preferably 1000 parts by mass or less, more preferably 800 parts by mass or less, and even more preferably 500 parts by mass or less.

[0274] (Amount of resin)

[0275] Regarding the amount of resin incorporated in step 6, from the viewpoint of improving resin moldability, it is preferably 1000 parts by mass or more, more preferably 2000 parts by mass or more, and even more preferably 5000 parts by mass or more, relative to 100 parts by mass of cellulose fibers bonded with modifying groups. On the other hand, from the viewpoint of improving heat resistance, the amount of resin incorporated is preferably 100,000 parts by mass or less, more preferably 50,000 parts by mass or less, and even more preferably 10,000 parts by mass or less. Here, the mass of cellulose fibers bonded with modifying groups is defined as the mass of only the cellulose fiber portion of the cellulose fibers bonded with modifying groups, that is, the mass of the cellulose fiber portion from which the modifying groups have been removed from the cellulose fibers bonded with modifying groups.

[0276] [Micronization process and short fiber processing]

[0277] Similar to method A above, the micronization process of cellulose fibers and / or the short fiberization process of cellulose fibers can be carried out at any stage of the manufacturing method of the present invention.

[0278] G. Method for manufacturing the resin composition including steps 7 and 8

[0279] A further embodiment of the method for manufacturing the resin composition of the present invention is a method for manufacturing a resin composition, which includes the following steps:

[0280] Step 7: A step of mixing cellulose fibers with ionic groups with one or more silane compounds selected from chlorosilane compounds, alkoxysilane compounds, acetoxysilane compounds, and silanol compounds to obtain cellulose fibers bonded with silane compounds; and

[0281] Step 8: A step of bonding modifying groups other than silanol groups to the ionic groups present in the cellulose fibers bonded with silane compounds, thereby obtaining modified cellulose fibers; and

[0282] The amount of the silane compound in step 7 is 50 parts by mass or more, relative to 100 parts by mass of the cellulose fiber portion of the cellulose fiber with ionic groups.

[0283] [Cellulose fibers with ionic groups]

[0284] The main properties of the "cellulose fibers with ionic groups" supplied to process 7 are the same as those in method A above.

[0285] [Preparation of cellulose fibers with ionic groups]

[0286] The preparation method of the "cellulose fiber with ionic groups" supplied to step 7 is the same as the preparation method in method A above.

[0287] [Step 7]

[0288] Step 7 in this invention is the same as step 3 in method B described above.

[0289] It is presumed that through mixing, at least a portion of the functional groups of the silane compound are converted into silanol groups, at least a portion of which react with at least a portion of the hydroxyl groups of the cellulose fiber having ionic groups, thereby bonding the cellulose fiber to the silane compound.

[0290] [Silane compounds]

[0291] The silane compound used in this process is the same as the silane compound in method A above.

[0292] (Amount of silane compound)

[0293] The amount of silane compound in step 7 is 50 parts by mass or more, relative to 100 parts by mass of cellulose fibers with ionic groups. Here, the mass of cellulose fibers with ionic groups is defined as the mass of the cellulose fiber portion only in the cellulose fibers with ionic groups, that is, the mass of the cellulose fiber portion from which the ionic groups have been removed.

[0294] From the viewpoint of improving the heat resistance of the resin composition and the resin molded article, the amount of silane compound is preferably 60 parts by mass or more, more preferably 70 parts by mass or more, and even more preferably 80 parts by mass or more. On the other hand, from the viewpoint of cost, the amount of silane compound is preferably 1000 parts by mass or less, more preferably 800 parts by mass or less, and even more preferably 500 parts by mass or less.

[0295] [Step 8]

[0296] Step 7 in this invention is the same as step 4 in method B described above.

[0297] [Resin]

[0298] The resin, curing agent, and curing accelerator used in method G are the same as those used in step 6 of method F above.

[0299] In method G, the resin can be compounded in step 7 or step 8.

[0300] When the resin is incorporated in step 7, the mixing temperature, mixing time, and solvents that can be used during mixing are the same as those in step 6.

[0301] (Amount of resin)

[0302] Regarding the amount of resin incorporated in step 7, from the viewpoint of improving resin moldability, it is preferably 1000 parts by weight or more, more preferably 2000 parts by weight or more, and even more preferably 5000 parts by weight or more, relative to 100 parts by weight of cellulose fibers with ionic groups. On the other hand, from the viewpoint of improving heat resistance, the amount of resin incorporated is preferably 100,000 parts by weight or less, more preferably 50,000 parts by weight or less, and even more preferably 10,000 parts by weight or less. Here, the mass of cellulose fibers with ionic groups is defined as the mass of only the cellulose fiber portion of the cellulose fibers with ionic groups, that is, the mass of the cellulose fiber portion with ionic groups removed from the cellulose fibers with ionic groups.

[0303] [Micronization process and short fiber processing]

[0304] Similar to method A above, the micronization process of cellulose fibers and / or the short fiberization process of cellulose fibers can be carried out at any stage of the manufacturing method of the present invention.

[0305] H. Resin Composition

[0306] The resin composition of the present invention is a resin composition formulated with the following components:

[0307] Modified cellulose fibers are cellulose fibers bonded with silane compounds and modified with groups other than silanol groups; and

[0308] Resin.

[0309] As a preferred example of the silane compound in the resin composition of the present invention, it is one or more silane compounds selected from chlorosilane compounds, alkoxysilane compounds, acetoxysilane compounds and silanol compounds. More specifically, the silane compounds mentioned in the item of "step 2" above can be cited.

[0310] From the viewpoint of improving the heat resistance of the resin composition and the resin molded article, the amount of the silane compound in the resin composition of the present invention is preferably 50 parts by mass or more relative to 100 parts by mass of the cellulose fiber portion of the cellulose fiber bonded with modification groups other than silanol groups. More specifically, from the same viewpoint, the amount of the silane compound is preferably 60 parts by mass or more, more preferably 70 parts by mass or more, and even more preferably 80 parts by mass or more. On the other hand, from the viewpoint of cost, the amount of the silane compound is preferably 1000 parts by mass or less, more preferably 800 parts by mass or less, and even more preferably 500 parts by mass or less.

[0311] In addition, details regarding the modified cellulose fibers or resins, and the proportions of each component constituting the resin composition, are as described in items A through D above.

[0312] The resin composition of the present invention can be manufactured, for example, by the manufacturing method of method F or method G described above.

[0313] The resin composition manufactured by the methods of F or G described above contains modified cellulose fibers and a resin. The resin composition may or may not contain a solvent. At least a portion of the modified cellulose fibers is bonded to the silane compound. Furthermore, unreacted products of the silane compound or oligomers thereof may be present in the resin composition.

[0314] The preferred contents of each component in the resin composition manufactured by the manufacturing method of method F or method G described above are as follows.

[0315] The content of cellulose fibers in the resin composition, that is, the amount of cellulose fiber portion other than the bonded modifying groups and the bonded silane compounds, is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1% by mass or more, from the viewpoint of improving the heat resistance of the resin. On the other hand, from the same viewpoint, it is preferably 20% by mass or less, more preferably 10% by mass or less, and even more preferably 5% by mass or less.

[0316] The content of silane compounds in the resin composition, that is, the total amount of silane compounds bonded to the modified cellulose fibers and silane compounds not bonded to the modified cellulose fibers, is preferably 0.03% by mass or more, more preferably 0.15% by mass or more, and even more preferably 0.3% by mass or more, from the viewpoint of improving the heat resistance of the resin. On the other hand, from the same viewpoint, it is preferably 40% by mass or less, more preferably 20% by mass or less, and even more preferably 10% by mass or less.

[0317] From the viewpoint of improving the heat resistance of the resin, the content of the modifying group in the resin composition is preferably 0.02% by mass or more, more preferably 0.1% by mass or more, and even more preferably 0.2% by mass or more. On the other hand, from the same viewpoint, it is preferably 70% by mass or less, more preferably 35% by mass or less, and even more preferably 20% by mass or less.

[0318] Regarding the resin content in the resin composition, from the viewpoint of improving the moldability of the resin, it is preferably 70% by mass or more, more preferably 75% by mass or more, and even more preferably 80% by mass or more. On the other hand, from the viewpoint of improving the heat resistance of the resin, it is preferably 95% by mass or less, more preferably 94% by mass or less, and even more preferably 93% by mass or less.

[0319] It should be noted that the content of each component can be calculated based on the proportions of each component.

[0320] The resin composition may or may not contain a solvent.

[0321] The preferred amounts of each component when the resin composition includes a solvent and a resin are as follows.

[0322] The content of cellulose fibers in the resin composition, that is, the amount of cellulose fiber portion other than the bonded modifying groups and the bonded silane compounds, is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1% by mass or more, from the viewpoint of improving the heat resistance of the resin. On the other hand, from the same viewpoint, it is preferably 20% by mass or less, more preferably 10% by mass or less, and even more preferably 5% by mass or less.

[0323] The content of silane compounds in the resin composition, that is, the total amount of silane compounds bonded to the modified cellulose fibers and silane compounds not bonded to the modified cellulose fibers, is preferably 0.03% by mass or more, more preferably 0.15% by mass or more, and even more preferably 0.3% by mass or more, from the viewpoint of improving the heat resistance of the resin. On the other hand, from the same viewpoint, it is preferably 40% by mass or less, more preferably 20% by mass or less, and even more preferably 10% by mass or less.

[0324] From the viewpoint of improving the heat resistance of the resin, the content of the modifying group in the resin composition is preferably 0.02% by mass or more, more preferably 0.1% by mass or more, and even more preferably 0.2% by mass or more. On the other hand, from the same viewpoint, it is preferably 70% by mass or less, more preferably 35% by mass or less, and even more preferably 20% by mass or less.

[0325] The solvent content in the resin composition is preferably 1% by mass or more, more preferably 5% by mass or more, and even more preferably 10% by mass or more. On the other hand, it is preferably 49% by mass or less, more preferably 45% by mass or less, and even more preferably 40% by mass or less.

[0326] Regarding the resin content in the resin composition, from the viewpoint of improving the moldability of the resin, it is preferably 70% by mass or more, more preferably 75% by mass or more, and even more preferably 80% by mass or more. On the other hand, from the viewpoint of improving the heat resistance of the resin, it is preferably 95% by mass or less, more preferably 94% by mass or less, and even more preferably 93% by mass or less.

[0327] It should be noted that the content of each component can be calculated based on the proportions of each component.

[0328] Solvents that may be used herein include, for example, methanol, ethanol, isopropanol (IPA), N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N,N-dimethylacetamide, tetrahydrofuran (THF), acetone, methyl ethyl ketone (MEK), cyclohexanone, ethyl acetate, acetonitrile, dichloromethane, chloroform, toluene, acetic acid, 1-methoxy-2-propanol (PGME), and water, which are preferred. These may be used alone or in combination of two or more.

[0329] [Other ingredients]

[0330] Without impairing the effects of the present invention, the resin composition may include, for example, plasticizers, crystal nucleating agents, fillers (inorganic fillers, organic fillers), hydrolysis inhibitors, flame retardants, antioxidants, lubricants as hydrocarbon waxes or anionic surfactants, ultraviolet absorbers, antistatic agents, antifogging agents, light stabilizers, pigments, mildew inhibitors, antibacterial agents, foaming agents, surfactants; starches, alginic acid and other polysaccharides; gelatin, animal glue, casein and other natural proteins; tannins, zeolites, ceramics, metal powders and other inorganic compounds; fragrances; flow regulators; leveling agents; conductive agents; ultraviolet dispersants; deodorizers, etc. Furthermore, without hindering the effects of the present invention, other polymeric materials or other compositions may also be added.

[0331] [Resin Molded Body]

[0332] Resin molded articles can be manufactured by molding cured products such as coatings formed from the resin composition. Resin molded articles can be manufactured by appropriately applying known molding methods such as coating molding, extrusion molding, injection molding, pressure molding, casting molding, or solvent casting to the composition of the present invention. From a productive point of view, coating molding and casting molding are preferred among these known molding methods.

[0333] The preferred contents of each component in the resin molded article are as follows.

[0334] The content of cellulose fibers in the resin molded body, that is, the amount of cellulose fiber portion other than the bonded modification groups and the bonded silane compounds, is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1% by mass or more, from the viewpoint of improving the heat resistance of the resin. On the other hand, from the same viewpoint, it is preferably 20% by mass or less, more preferably 10% by mass or less, and even more preferably 5% by mass or less.

[0335] The content of silane compounds in the resin molded body, that is, the total amount of silane compounds bonded to the modified cellulose fibers and silane compounds not bonded to the modified cellulose fibers, is preferably 0.03% by mass or more, more preferably 0.15% by mass or more, and even more preferably 0.3% by mass or more, from the viewpoint of improving the heat resistance of the resin. On the other hand, from the same viewpoint, it is preferably 40% by mass or less, more preferably 20% by mass or less, and even more preferably 10% by mass or less.

[0336] From the viewpoint of improving the heat resistance of the resin, the content of the modifying group in the resin molded article is preferably 0.02% by mass or more, more preferably 0.1% by mass or more, and even more preferably 0.2% by mass or more. On the other hand, from the same viewpoint, it is preferably 70% by mass or less, more preferably 35% by mass or less, and even more preferably 20% by mass or less.

[0337] Regarding the resin content in the resin molded article, from the viewpoint of improving the moldability of the resin, it is preferably 70% by mass or more, more preferably 75% by mass or more, and even more preferably 80% by mass or more. On the other hand, from the viewpoint of improving the heat resistance of the resin, it is preferably 99% by mass or less, more preferably 95% by mass or less, even more preferably 94% by mass or less, even more preferably 93% by mass or less, even more preferably 90% by mass or less, even more preferably 80% by mass or less, and even more preferably 70% by mass or less.

[0338] It should be noted that the content of each component can be calculated based on the proportions of each component.

[0339] I. Applications of the Invention

[0340] The modified cellulose fibers obtained by the manufacturing method of the present invention, compositions comprising the modified cellulose fibers, resin additives, and resin compositions obtained by the manufacturing method of the present invention are suitable for use in the following fields: Semiconductor applications, specifically photoresist, buffer coatings, redistribution materials, back-grinding tapes, die-cutting tapes, die-attach films, epoxy sealants, film sealants, underfill adhesives, mold underfill adhesives, CMP pads, printed circuit board materials, etc. Display applications, specifically polarizing element protective films, surface treatment films, backlight film films, QD sheets, protective films, transparent conductive films, cover sheets, back panels, foldable cover sheets, phase reversal films for circular polarizers, OLED substrates, OLED sealants, OLED shielding materials, etc. Automotive applications, specifically millimeter-wave radar-related trim materials, LiDAR interference filters, automotive lens materials, automotive OCA, OCR, interlayer films, connector terminals, motor insulating sheets, etc. Passive component applications include, specifically, aluminum electrolytic capacitors, film capacitors, multilayer ceramic capacitors, inductors, and rheostats. Electromagnetic wave material applications include, specifically, electromagnetic wave shielding and noise suppression shielding. Optical material applications include, specifically, dimming glass / films, projector screen films, graphite sheets, LED phosphor materials, and optical fibers. Heat dissipation material applications include, specifically, heat dissipation metals, heat dissipation resin substrates, heat dissipation sheets, phase change sheets, thermal greases, thermal gap fillers, and thermally dissipative adhesives. Transportation equipment material applications include, specifically, exterior components, engine components, and structural materials for automobiles, trains, ships, and aircraft.

[0341] In relation to the above embodiments, the present invention also discloses the following resin composition, resin molded body, method for manufacturing modified cellulose fiber, method for manufacturing resin composition, and modified cellulose fiber.

[0342] <1> A resin composition comprising: modified cellulose fibers, which are formed by bonding cellulose fibers with modification groups other than silanol groups to a silane compound; and

[0343] Resin.

[0344] <2> The resin composition described in <1> above, wherein the modifying groups other than silanol groups are bonded to cellulose fibers by means of ionic and / or covalent bonds.

[0345] <3> The resin composition described in <1> or <2> above, wherein the modifying groups other than silanol groups are hydrocarbon groups and / or polymer groups.

[0346] <4> The resin composition described in any one of <1> to <3> above, wherein the modifying group other than the silanol group is a hydrocarbon group, and the carbon number is 1 or more, preferably 3 or more, more preferably 8 or more, and even more preferably 10 or more, on the other hand, preferably 30 or less, more preferably 22 or less, and even more preferably 18 or less.

[0347] <5> The resin composition described in any one of <1> to <4> above, wherein the modifying group other than the silanol group is a polymer group, and its molecular weight is preferably 100 or more, more preferably 200 or more, more preferably 300 or more, more preferably 400 or more, even more preferably 600 or more, even more preferably 1,000 or more, even more preferably 1,500 or more, on the other hand, preferably 10,000 or less, more preferably 7,000 or less, even more preferably 5,000 or less, even more preferably 4,000 or less, even more preferably 3,500 or less, even more preferably 2,500 or less.

[0348] <6> The resin composition described in any one of <1> to <5> above, wherein the modifying group other than the silanol group is a polymer group, which preferably has functional groups with repeating structures connected by structures having oxygen atoms, more preferably functional groups with repeating structures connected by oxygen atoms such as polyoxyalkylene structures (epoxyalkylene chains) and polysiloxane structures (silicone chains), further preferably functional groups with polyoxyalkylene structures, and even more preferably alkoxy polyoxyalkylene structures.

[0349] <7> The resin composition described in any one of <1> to <6> above, wherein the content or amount of modified cellulose fiber in the resin composition is preferably 4.0% by mass or more, more preferably 5.0% by mass or more, and even more preferably 6.0% by mass or more, and on the other hand, preferably 20% by mass or less, more preferably 15% by mass or less, and even more preferably 10% by mass or less.

[0350] <8> The resin composition described in any one of <1> to <7> above, wherein the content or amount of cellulose fiber in the resin composition is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1% by mass or more. On the other hand, it is preferably 20% by mass or less, more preferably 10% by mass or less, and even more preferably 5% by mass or less.

[0351] <9> The resin composition described in any one of <1> to <8> above, wherein the mass ratio of the amount of modified cellulose fiber in the resin composition to the amount of resin (amount of modified cellulose fiber / amount of resin) is preferably 5 / 95 or more, more preferably 6 / 94 or more, and even more preferably 7 / 93 or more. On the other hand, it is preferably 20 / 80 or less, more preferably 15 / 85 or less, and even more preferably 10 / 90 or less.

[0352] <10> The resin composition as described in any one of <1> to <9> above, wherein the mass ratio of the amount of cellulose fiber in the resin composition to the amount of resin (amount of cellulose fiber / amount of resin) is preferably 0.1 / 99.9 or more, more preferably 0.5 / 99.5 or more, and even more preferably 1 / 99 or more. On the other hand, it is preferably 20 / 80 or less, more preferably 10 / 90 or less, and even more preferably 5 / 95 or less.

[0353] <11> The resin composition described in any one of <1> to <10> above, wherein the resin content in the resin composition is preferably 70% by mass or more, more preferably 75% by mass or more, even more preferably 80% by mass or more, and on the other hand, preferably 95% by mass or less, more preferably 94% by mass or less, and even more preferably 93% by mass or less.

[0354] <12> The resin composition described in any one of <1> to <11> above, wherein the content or amount of modified cellulose fiber in the resin composition is preferably 4.0% by mass or more, more preferably 5.0% by mass or more, and even more preferably 6.0% by mass or more, and on the other hand, preferably 20% by mass or less, more preferably 15% by mass or less, and even more preferably 10% by mass or less, and the content or amount of cellulose fiber in the resin composition is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1% by mass or more, and on the other hand, preferably 20% by mass or less, more preferably 10% by mass or less, and even more preferably 5% by mass or less, and the mass ratio of the amount of modified cellulose fiber in the resin composition to the amount of resin (amount of modified cellulose fiber / amount of resin) is preferably 5 / 9. The ratio of the amount of cellulose fiber in the resin composition to the amount of resin (the mass ratio of the amount of cellulose fiber to the amount of resin) is preferably 0.1 / 99.9 or more, more preferably 0.5 / 99.5 or more, and more preferably 1 / 99 or more. Alternatively, the ratio is preferably 20 / 80 or less, more preferably 10 / 90 or less, and more preferably 5 / 95 or less. The resin content in the resin composition is preferably 70% by mass or more, more preferably 75% by mass or more, and more preferably 80% by mass or more. Alternatively, the ratio is preferably 95% by mass or less, more preferably 94% by mass or less, and more preferably 93% by mass or less.

[0355] <13> The resin composition described in any one of <1> to <12> above, wherein the modifying group other than the silanol group is a functional group having a polyoxyalkylene structure, the polyoxyalkylene structure preferably being a (co)polymer structure of one or more oxyalkylene groups having 2 or more and 8 or fewer carbon atoms, more preferably a (co)polymer structure of one or more oxyalkylene groups having 2 or more and 4 or fewer carbon atoms, even more preferably a (co)polymer structure of one or two oxyalkylene groups selected from ethylene oxide (EO) and propylene oxide (PO), and even more preferably a copolymer structure formed by random or block polymerization of ethylene oxide (EO) and propylene oxide (PO) (also called (EO / PO) structure).

[0356] <14> A method for manufacturing modified cellulose fibers, comprising the following steps:

[0357] Step 1: A step of bonding a modifying group other than a silanol group to the ionic group of a cellulose fiber, thereby obtaining a cellulose fiber bonded with the modified group; and

[0358] Step 2: A step of mixing the cellulose fibers with the above-mentioned modified groups with one or more silane compounds selected from chlorosilane compounds, alkoxysilane compounds, acetoxysilane compounds, and silanol compounds; and

[0359] The amount of the silane compound in step 2 is 50 parts by mass or more, relative to 100 parts by mass of the cellulose fiber portion of the cellulose fiber bonded with the modified group.

[0360] <15> A method for manufacturing modified cellulose fibers, comprising the following steps:

[0361] Step 3: A step of mixing cellulose fibers with ionic groups with one or more silane compounds selected from chlorosilane compounds, alkoxysilane compounds, acetoxysilane compounds, and silanol compounds to obtain cellulose fibers bonded with silane compounds; and

[0362] Step 4: A step of bonding modifying groups other than silanol groups to the ionic groups of the cellulose fibers bonded with silane compounds, thereby obtaining modified cellulose fibers; and

[0363] The amount of the silane compound in step 3 is 50 parts by mass or more, relative to 100 parts by mass of the cellulose fiber portion of the cellulose fiber with ionic groups.

[0364] <16> A method for manufacturing a resin composition, comprising the following steps:

[0365] Step 5: A step of bonding a modifying group other than a silanol group to the ionic group of a cellulose fiber, thereby obtaining a cellulose fiber bonded with the modified group; and

[0366] Step 6: A step of mixing one or more silane compounds selected from chlorosilane compounds, alkoxysilane compounds, acetoxysilane compounds, and silanol compounds, the aforementioned cellulose fibers with bonded modification groups, and the resin; and

[0367] The amount of the silane compound in step 6 is 50 parts by mass or more, relative to 100 parts by mass of the cellulose fiber portion of the cellulose fiber bonded with the modified group.

[0368] <17> A method for manufacturing a resin composition, comprising the following steps:

[0369] Step 7: A step of mixing cellulose fibers with ionic groups with one or more silane compounds selected from chlorosilane compounds, alkoxysilane compounds, acetoxysilane compounds, and silanol compounds to obtain cellulose fibers bonded with silane compounds; and

[0370] Step 8: A step of bonding modifying groups other than silanol groups to the ionic groups present in the cellulose fibers bonded with silane compounds, thereby obtaining modified cellulose fibers; and

[0371] The amount of the silane compound in step 7 is 50 parts by mass or more, relative to 100 parts by mass of the cellulose fiber portion of the cellulose fiber with ionic groups.

[0372] <18> The method for manufacturing modified cellulose fibers or resin compositions as described in any of <14> to <17> above, wherein the modifying groups other than silanol groups are bonded to the cellulose fibers by ionic and / or covalent bonds.

[0373] <19> The method for manufacturing modified cellulose fibers or resin compositions as described in any of <14> to <18> above, wherein the modifying groups other than silanol groups are hydrocarbon groups and / or polymer groups.

[0374] <20> The method for manufacturing modified cellulose fibers or resin compositions as described in any one of <14> to <19> above, wherein the modifying group other than the silanol group is a hydrocarbon group, and the number of carbon atoms is 1 or more, preferably 3 or more, more preferably 8 or more, and even more preferably 10 or more. On the other hand, it is preferably 30 or less, more preferably 22 or less, and even more preferably 18 or less.

[0375] <21> The method for manufacturing modified cellulose fibers or resin compositions as described in any one of <14> to <20> above, wherein the modifying group other than the silanol group is a polymer group, and its molecular weight is preferably 100 or more, more preferably 200 or more, more preferably 300 or more, more preferably 400 or more, even more preferably 600 or more, even more preferably 1,000 or more, even more preferably 1,500 or more, on the other hand, preferably 10,000 or less, more preferably 7,000 or less, even more preferably 5,000 or less, even more preferably 4,000 or less, even more preferably 3,500 or less, even more preferably 2,500 or less.

[0376] <22> The method for manufacturing modified cellulose fibers or resin compositions as described in any of <14> to <21> above, wherein the modifying group other than the silanol group is a polymer group, which preferably has functional groups with repeating structures connected by structures having oxygen atoms, more preferably functional groups with repeating structures connected by oxygen atoms such as polyoxyalkylene structures (epoxyalkylene chains) and polysiloxane structures (silicone chains), further preferably functional groups with polyoxyalkylene structures, and even more preferably alkoxy polyoxyalkylene structures.

[0377] <23> The method for manufacturing modified cellulose fibers or resin compositions as described in any of <14> to <22> above, wherein the modifying group other than the silanol group is a functional group having a polyoxyalkylene structure, the polyoxyalkylene structure preferably being a (co)polymer structure of one or more oxyalkylene groups having 2 or more and 8 or fewer carbon atoms, more preferably a (co)polymer structure of one or more oxyalkylene groups having 2 or more and 4 or fewer carbon atoms, even more preferably a (co)polymer structure of one or two oxyalkylene groups selected from ethylene oxide (EO) and propylene oxide (PO), and even more preferably a copolymer structure formed by random or block polymerization of ethylene oxide (EO) and propylene oxide (PO) (also called (EO / PO) structure).

[0378] <24> The method for manufacturing modified cellulose fibers or resin compositions as described in any of <14> to <23> above, wherein the modifying compound is preferably a compound having a modifying group and a cationic group, and more preferably a compound having a modifying group and an amino or quaternary ammonium group.

[0379] <25> The method for manufacturing modified cellulose fibers or the method for manufacturing resin compositions as described in any one of <14> to <24> above, wherein the amount of the modifying compound used in step 1 is preferably 0.10 equivalents or more, more preferably 0.15 equivalents or more, and even more preferably 0.2 equivalents or more. On the other hand, it is preferably 20 equivalents or less, more preferably 5 equivalents or less, even more preferably 1 equivalent or less, and even more preferably 0.7 equivalents or less.

[0380] <26> The method for manufacturing modified cellulose fibers or the method for manufacturing resin compositions as described in any one of <14> to <25> above, wherein the crystallinity of the cellulose fibers having ionic groups is preferably 10% or more, more preferably 15% or more, even more preferably 20% or more, even more preferably 30% or more, even more preferably 40% or more, even more preferably 50% or more, and on the other hand, preferably 90% or less, more preferably 85% or less, even more preferably 80% or less.

[0381] <27> The method for manufacturing modified cellulose fibers or the method for manufacturing resin compositions as described in any one of <14> to <26> above, wherein the average fiber diameter of the cellulose fibers bonded with the modification group is preferably 1 nm or more, more preferably 2 nm or more, and on the other hand, preferably 300 nm or less, more preferably 200 nm or less, further preferably 150 nm or less, and even more preferably 120 nm or less.

[0382] <28> The method for manufacturing modified cellulose fibers or the method for manufacturing resin compositions as described in any one of <14> to <27> above, wherein the average fiber length of the cellulose fibers bonded with the modification group is preferably 10 nm or more, more preferably 30 nm or more, and even more preferably 50 nm or more, and on the other hand, preferably 1000 nm or less, more preferably 500 nm or less, and even more preferably 300 nm or less.

[0383] <29> The method for manufacturing modified cellulose fibers or resin compositions as described in any one of <14> to <28> above, wherein the amount of the modified group bonded in the cellulose fiber bonded with the modified group is preferably 0.01 mmol / g or more, and on the other hand, preferably 3.0 mmol / g or less.

[0384] <30> The method for manufacturing modified cellulose fibers or resin compositions as described in any of <14> to <29> above, wherein the temperature during mixing, i.e. the reaction temperature, is preferably 70°C or lower, more preferably 50°C or lower, and even more preferably 30°C or lower. On the other hand, it is preferably -20°C or higher, more preferably -10°C or higher, and more preferably -5°C or higher.

[0385] <31> The method for manufacturing modified cellulose fibers or resin compositions as described in any one of <14> to <30> above, wherein the mixing time is preferably 0.1 hours or more, more preferably 0.5 hours or more, and even more preferably 1 hour or more, and on the other hand, preferably 120 hours or less, more preferably 72 hours or less, even more preferably 48 hours or less, and even more preferably 24 hours or less.

[0386] <32> In the method for manufacturing modified cellulose fibers or resin compositions as described in any one of <14> to <31> above, the amount of silane compound is preferably 60 parts by mass or more, more preferably 70 parts by mass or more, and even more preferably 80 parts by mass or more. On the other hand, it is preferably 1,000 parts by mass or less, more preferably 800 parts by mass or less, and even more preferably 500 parts by mass or less.

[0387] <33> A modified cellulose fiber manufactured by a method for manufacturing modified cellulose fibers as described in any one of <14> to <32> above.

[0388] <34> A resin molded article comprising a resin composition as described in any one of <1> to <13> above.

[0389] [Example]

[0390] The present invention will now be specifically described with reference to embodiments. It should be noted that the following embodiments are merely illustrative of the invention and are not intended to limit it in any way. It should also be noted that "atmospheric pressure" means 101.3 kPa and "room temperature" means 25°C.

[0391] [Average fiber diameter and average fiber length of (short fiber) anion-modified cellulose fibers]

[0392] A dispersion containing 0.01% by mass was prepared by adding deionized water to the cellulose fibers of the test subject or a suspension containing the cellulose fibers of the test subject. The dispersion was measured using a wet dispersion image analysis particle size analyzer (JASCO INTERNATIONAL, trade name: IF-3200) under the following conditions: front lens: 2x, telecentric variable focal length lens: 1x, image resolution: 0.835 μm / pixel, syringe inner diameter: 6515 μm, spacer thickness: 500 μm, image recognition mode: ghosting, threshold: 8, sample volume: 1 mL, and sampling rate: 15%. Furthermore, the cellulose fibers were approximated as rectangles, with the length of the minor axis defined as the fiber diameter and the length of the major axis defined as the fiber length. The values ​​were measured for 100 cellulose fibers, and the average value was calculated.

[0393] [Average fiber diameter and average fiber length of cellulose fibers after micronization treatment]

[0394] To prepare a dispersion containing 1% by mass, deionized water was added to the cellulose fibers of the test subject or a dispersion containing the cellulose fibers of the test subject. After preparing the dispersion to pH = 9 using sodium hydroxide, it was dispersed five times at 150 MPa using a high-pressure homogenizer (Yoshida Machinery Kogyo Co., Ltd., NanoVater L-ES). Deionized water was added to the dispersion to achieve a cellulose fiber content of 0.01% by mass. The dispersion was dropped onto mica, and the resulting sample, after removing the water droplets with air and drying, was used as the observation sample. Measurements were performed using an atomic force microscope (AFM) (Hitachi High-Tech Co., Ltd., AFM-5100N; probe used was Hitachi High-Tech Co., Ltd., SI-DF20P2) in dynamic force mode. At this point, more than 100 cellulose fibers were extracted from the microscope image where the cellulose fibers could be identified, and the average fiber diameter was calculated based on the fiber height. The average fiber length was calculated based on the distance along the fiber direction.

[0395] [Carboxyl content in TEMPO oxidized cellulose fibers]

[0396] Take 0.5 g of the dried cellulose fiber of the test subject and place it in a 100 mL beaker. Add ion-exchanged water or a methanol / water mixture of 2 / 1, making the total volume 55 mL. Add 5 mL of 0.01 M sodium chloride aqueous solution to prepare a dispersion. Stir the dispersion until the cellulose fiber of the test subject is fully dispersed. Add 0.1 M hydrochloric acid to the dispersion to adjust the pH to 2.5–3. Using an automatic titrator (manufactured by Toa DKK Corporation, trade name "AUT-701"), add 0.05 M sodium hydroxide aqueous solution dropwise to the dispersion after a 60-second waiting time, and measure the conductivity and pH value every minute. Continue the measurement until the pH value reaches approximately 11 to obtain a conductivity curve. Calculate the sodium hydroxide titration amount based on the conductivity curve, and calculate the anionic group content of the cellulose fiber of the test subject according to the following formula.

[0397] Carboxyl content (mmol / g) = sodium hydroxide titration volume × sodium hydroxide aqueous solution concentration (0.05M) / mass of cellulose fiber of the test subject (0.5g)

[0398] [Content of each ingredient]

[0399] The content of each component other than water is calculated based on the proportions of each component.

[0400] The water content in the dispersion or suspension was determined by Karl von Schüco titration using a CA-200 manufactured by MITSUBISHI ANALYTECH.

[0401] Regarding the concentration of solid components in various cellulose fibers, the moisture concentration in the sample was measured using an infrared moisture meter (manufactured by Shimadzu Corporation, MC-120H), and calculated based on the difference from 100% by mass. For a 1g sample, the moisture concentration was measured every 30 seconds at a constant temperature of 150°C, and the value displayed was the moment when the mass decreased to less than 0.1% within 30 seconds.

[0402] [Determination of the conductivity of the filtrate]

[0403] The conductivity of the filtrate was measured using a small conductivity meter (manufactured by Horiba Seisakusho Co., Ltd., LAQUAtwin EC-33B).

[0404] [Determination of the average degree of polymerization of anionic modified cellulose fibers]

[0405] The average degree of polymerization of anionic modified cellulose fibers was determined by the following method.

[0406] (1) Preparation of the solution for determination

[0407] Accurately weigh 0.06 g (dry weight) of the anion-modified cellulose fiber to be tested and place it in a 50 mL beaker. Add water to make the solid content concentration 1% by mass. Add 0.006 g of sodium borohydride, stir at room temperature for 2 hours, then add 18 g of acetone. Centrifuge using a high-speed refrigerated centrifuge (Koki Holdings, CR21G III) at 10°C, 10,000 G, for 1 minute and remove the supernatant. Add 18 g of ethanol to the residue, and repeat the centrifugation and supernatant removal process three times to obtain a precipitate washed with ethanol. Dry the obtained precipitate under vacuum at 40°C for 12 hours to obtain reduced pulp in which the aldehyde groups in the anion-modified cellulose fiber are reduced. Add 15 mL of deionized water and 15 mL of 1M copper ethylenediamine solution to 0.06 g of the obtained reduced pulp, stir at room temperature for 1 hour, and obtain the test solution.

[0408] (2) Determination of average degree of polymerization

[0409] The solution obtained in (1) above is placed in the Ubbelohde viscometer and left to stand in a constant temperature bath at (20±0.1)℃ for 1 hour. The flow time of the liquid (t (seconds)) and the flow time of the copper ethylenediamine solution without cellulose (t0 (seconds)) are measured, and the intrinsic viscosity [η] (dL / g) is calculated according to the following formula.

[0410] [η]=[(t / t0-1) / c] / [1+0.28×(t / t0-1)]

[0411] (c: cellulose concentration (g / dL))

[0412] Based on the obtained intrinsic viscosity [η], the average degree of polymerization (DP) of the anion-modified cellulose fiber is calculated according to the following formula. v ).

[0413] [η] = 0.094 × 162 × DP v 0.67

[0414] [Bonding amount and introduction rate of modifying groups in various cellulose fibers]

[0415] The bonding amount of the modifying group is determined by the following IR measurement method, and its bonding amount and absorption rate are calculated according to the following formulas. Regarding the IR measurement, for example, when the modifying group is bonded to TEMPO oxidized cellulose fibers, an infrared absorption spectrometer (IR) (manufactured by Thermo Fisher Scientific, trade name: Nicolet 6700) is used to measure the dried TEMPO oxidized cellulose fibers or cellulose fibers bonded with the modifying group by the ATR method, and the bonding amount and absorption rate of the modifying group are calculated according to the following formulas A and B.

[0416] <Form A>

[0417] The amount of modified group bonded (mmol / g) = a × (b - c) ÷ d

[0418] a: Carboxyl group content (mmol / g) of TEMPO oxidized cellulose fiber

[0419] b: 1720cm of TEMPO oxidized cellulose fiber -1 peak intensity

[0420] c: 1720 cm of cellulose fiber with bonded modification groups -1 peak intensity

[0421] d: 1720cm of TEMPO oxidized cellulose fiber -1 peak intensity

[0422] 1720cm -1 Peak intensity: Peak intensity derived from the carbonyl group of a carboxylic acid

[0423] <Form B>

[0424] The introduction rate of the modifying group (mol%) = 100 × e / f

[0425] e: Amount of the modifying group bonded (mmol / g)

[0426] f: Carboxyl content of TEMPO oxidized cellulose fibers (mmol / g)

[0427] [Cellulose fiber content (converted amount) in various cellulose fibers]

[0428] The amount of cellulose fiber (converted amount) in various cellulose fibers refers to the amount of cellulose fiber alone after removing the modifying groups. In this invention, the modified cellulose fibers have modifying groups with considerably large molecular weights (e.g., greater than the molecular weight of glucose). Therefore, in this specification, where it is more appropriate to describe the process excluding differences in the molecular weights of the modifying groups, the amount of cellulose fiber constituting the modified cellulose fiber is not expressed as the amount of modified cellulose fiber, but rather as the amount of cellulose fiber (converted amount) constituting the modified cellulose fiber.

[0429] Cellulose fiber content (converted content) is determined by the following method.

[0430] (a) The case where only one "modifying compound" is added.

[0431] The amount of cellulose fiber (converted quantity) is calculated according to the following formula E.

[0432] <Formula E>: Cellulose fiber weight (converted weight) (g) = Mass of cellulose fibers bonded with modifying groups (g) / [1 + Molecular weight of the modifying compound (g / mol) × Bonding amount of modifying groups (mmol / g) × 0.001]

[0433] (b) The case where two or more "modifying compounds" are added.

[0434] Considering the molar ratio of each compound (i.e., the molar ratio when the total molar amount of the added modifying compounds is set to 1), the amount of cellulose fiber (converted amount) is calculated.

[0435] [Confirmation of the crystalline structure in various cellulose fibers]

[0436] The crystal structure of various cellulose fibers, including cellulose fiber raw materials, cellulose fibers with ionic groups, or modified cellulose fibers, was confirmed by the following method: using a diffractometer (manufactured by Rigaku Corporation, trade name: MiniFlexII), the determination was performed under the following conditions.

[0437] Granulation preparation conditions were determined: using a tablet forming machine, pressure was applied to the cellulose fibers to be freeze-dried within the range of 10–20 MPa, thereby preparing granules with an area of ​​320 mm². 2 Smooth particles with a thickness of 1mm.

[0438] X-ray diffraction analysis conditions: step angle 0.01°, scanning speed 10° / min, measurement range: diffraction angle 2θ = 5–40°

[0439] X-ray source: Cu / Kα-rays, tube voltage: 15 kV, tube current: 30 mA

[0440] Peak segmentation condition: After removing background noise, fit using a Gaussian function with an error of 2θ = 13-23° within 5%.

[0441] The crystalline structures of various cellulose fibers were confirmed by the following method: measurements were performed using the diffractometer described above under the conditions described above.

[0442] The crystallinity of the type I cellulose crystal structure is calculated using the area of ​​the X-ray diffraction peaks obtained by the above peak division, based on the following formula (A).

[0443] Type I cellulose crystallinity (%) = [I cr / (I cr +I am )]×100 (A)

[0444] [In the formula, I] cr I represents the area of ​​the diffraction peak of the lattice plane (002 plane) (diffraction angle 2θ = 22-23°) in X-ray diffraction. am [This represents the area of ​​the diffraction peak in the amorphous region (diffraction angle 2θ = 18.5°)]

[0445] Preparation Example 1 (Preparation of Short Fiber Anion-Modified Cellulose Fibers)

[0446] [Anion-modified cellulose fiber]

[0447] Anionic modified cellulose fibers with the physical properties listed in Table 1 were used as raw materials.

[0448] [Table 1]

[0449]

[0450] The anion-modified cellulose fiber can be prepared, for example, by the TEMPO oxidation treatment described below.

[0451] [TEMPO oxidation treatment]

[0452] 10g of bleached kraft pulp fiber from coniferous trees (natural cellulose fiber) and 990g of deionized water were measured and placed in a 2L PP beaker equipped with a mechanical stirrer and stirring blades. The mixture was stirred at 25°C and 100 rpm for 30 minutes. Then, relative to the 10g of pulp fiber, 0.13g of 2,2,6,6-tetramethyl-1-piperidin-N-hydroxyl (TEMPO), 1.3g of sodium bromide, and 35.5g of a 10.5% (w / w) sodium hypochlorite aqueous solution were added sequentially. A fixed pH value was then maintained at 10.5 by adding 0.5M sodium hydroxide aqueous solution. The reaction was carried out at 25°C with stirring at 100 rpm for 120 minutes. Then, while stirring, 0.01M hydrochloric acid was added to adjust the pH of the suspension to 2. Finally, the solid components were separated by vacuum filtration. Repeat the following steps until the conductivity of the filtrate is below 200 μS / cm: disperse the solid components in deionized water and separate them by vacuum filtration. Dehydrate the obtained solid components to obtain anion-modified cellulose fibers.

[0453] [Preparation of Short-Fiber Anion-Modified Cellulose Fibers]

[0454] Short-fiber anion-modified cellulose fibers with the physical properties listed in Table 1 were prepared by alkaline hydrolysis and hot water treatment.

[0455] [Table 2]

[0456]

[0457] The short-fiber anion-modified cellulose fiber can be prepared, for example, by alkaline hydrolysis and hot water treatment.

[0458] [Alkaline hydrolysis treatment]

[0459] A suspension of anionic modified cellulose fibers with 144.5 g of solids and the properties listed in Table 1 was diluted with 1000 g of deionized water. 1.4 g of 35% hydrogen peroxide solution was added (1 part by mass of hydrogen peroxide per 100 parts by mass of the raw cellulose fibers), and the pH was adjusted to 12 using a 1M sodium hydroxide aqueous solution. Then, an alkaline hydrolysis treatment was performed at 80°C for 2 hours (solids concentration of the anionic modified cellulose fiber suspension was 4.3% by mass). After cooling the suspension to room temperature, 0.01M hydrochloric acid was added to set the pH to 2. The solids were separated from the suspension by vacuum filtration.

[0460] [Hot Water Treatment]

[0461] The solid components obtained through the above alkaline hydrolysis treatment were dispersed in deionized water, and the solid components were repeatedly separated by vacuum filtration until the conductivity of the filtrate was below 200 μS / cm. Deionized water was added to the suspension at a solid component concentration of 5% by mass, and the mixture was stirred at 95°C for 12 hours. Afterward, it was cooled to room temperature, thereby obtaining an aqueous suspension of short-fiber anion-modified cellulose fibers. Short-fiber anion-modified cellulose fibers were obtained by centrifugation of the obtained aqueous suspension. It should be noted that, as a property of the short-fiber anion-modified cellulose fibers after micronization, the average fiber diameter was 3.9 nm and the average fiber length was 130 nm.

[0462] Preparation Example 2 (Preparation of a composition containing cellulose fibers 1 with bonded modifying groups and a resin)

[0463] Short-fibered anionic modified cellulose fibers having the properties listed in Table 2 were added to 1-methoxy-2-propanol (PGME) to obtain a dispersion with a solid content concentration of 2.0% by mass. 4.1 g of EO / PO amine was added relative to 300 g of the obtained dispersion, and the mixture was stirred at 25°C for 1 hour to obtain a dispersion of cellulose fibers bonded with the modified group. Here, the amount of EO / PO amine used as the modifying compound was 0.26 equivalents relative to the ionic group (carboxyl group) of the aforementioned short-fibered anionic modified cellulose fibers.

[0464] 300 g of epoxy resin was further added to the obtained cellulose fiber dispersion with bonded modified groups. After stirring at 25°C for 1 hour, the mixture was dispersed five times at 150 MPa using a high-pressure homogenizer (Yoshida Machinery Co., Ltd., NanoVater L-ES). Subsequently, PGME was removed from the cellulose fiber dispersion with bonded modified groups by distillation using an evaporator, thereby obtaining a composition containing cellulose fiber 1 with bonded modified groups and resin. The obtained composition is a liquid at room temperature.

[0465] Preparation Example 3 (Preparation of a composition containing cellulose fibers 2 with bonded modified groups and a resin)

[0466] Short-fibered anionic modified cellulose fibers having the properties listed in Table 2 were added to 1-methoxy-2-propanol (PGME) to obtain a dispersion with a solid content concentration of 2.0% by mass. 1.4 g of trioctylamine was added relative to 300 g of the obtained dispersion, and the mixture was stirred at 25°C for 1 hour to obtain a dispersion of cellulose fibers bonded with the modified group. Here, the amount of trioctylamine used as the modifying compound is 0.5 equivalents relative to the ionic group (carboxyl group) of the aforementioned short-fibered anionic modified cellulose fibers.

[0467] 300 g of epoxy resin was added to the obtained cellulose fiber dispersion with bonded modified groups. After stirring at 25°C for 1 hour, the mixture was dispersed five times at 150 MPa using a high-pressure homogenizer (Yoshida Machinery Co., Ltd., NanoVater L-ES). Subsequently, PGME was removed from the cellulose fiber dispersion with bonded modified groups by distillation using an evaporator, thereby obtaining a composition containing cellulose fibers 2 with bonded modified groups and resin. The obtained composition is a liquid at room temperature.

[0468] Example 1 (A composition containing modified cellulose fibers and resin)

[0469] In Preparation Example 2, 4 g of the composition (containing 0.13 g of cellulose fiber 1 with bonded modified groups (0.08 g of cellulose fiber portion from which the modified groups were removed) and 3.87 g of resin, 0.2 g of curing agent and 0.12 g of curing accelerator were added. The mixture was stirred for 10 minutes at 25°C and 2000 rpm using an automatic rotary mixer (Thinky Corporation, defoaming Rintaro), and then defoamed for 2 minutes at 25°C and 2200 rpm. Subsequently, 0.048 g of the silane compound 3-aminopropyltrimethoxysilane was added, and the mixture was stirred for 5 minutes at 25°C and 2000 rpm using an automatic rotary mixer (Thinky Corporation, defoaming Rintaro), and then defoamed for 2 minutes at 25°C and 2200 rpm to obtain the composition described in Table 3.

[0470] Example 2

[0471] Except for changing the amount of silane compound added to 0.16g, the same treatment as in Example 1 above was performed to obtain the composition described in Table 3.

[0472] Example 3

[0473] Except for changing the silane compound to N-phenyl-3-aminopropyltrimethoxysilane and changing its addition amount to 0.16g, the same treatment as in Example 1 above was performed to obtain the composition described in Table 4.

[0474] Example 4

[0475] Except for changing the silane compound to n-propyltrimethoxysilane and changing its addition amount to 0.16g, the same treatment as in Example 1 above was performed to obtain the composition described in Table 4.

[0476] Example 5

[0477] In Preparation Example 3, 3.97 g of the composition (containing 0.10 g of cellulose fiber 2 with bonded modified groups (0.08 g of cellulose fiber portion from which the modified groups were removed) and 3.87 g of resin) was mixed with 0.2 g of curing agent and 0.12 g of curing accelerator. The mixture was stirred for 10 minutes at 2000 rpm using an automatic rotary mixer (Thinky Corporation, defoaming Rintaro), and then defoamed for 2 minutes at 25°C and 2200 rpm. Subsequently, 0.16 g of the silane compound 3-aminopropyltrimethoxysilane was added, and the mixture was stirred for 5 minutes at 2000 rpm using an automatic rotary mixer (Thinky Corporation, defoaming Rintaro), and then defoamed for 2 minutes at 25°C and 2200 rpm to obtain the composition described in Table 4.

[0478] Comparative Example 1 and Comparative Example 2

[0479] Except for changing the amount of silane compound added to 0g (Comparative Example 1) or 0.016g (Comparative Example 2), the same treatment as in Example 1 was performed to obtain the composition described in Table 3.

[0480] Comparative Example 3

[0481] Adding short fibrous anionic modified cellulose fibers with the physical properties listed in Table 2 to PGME, i.e., cellulose fibers with ionic groups, yields a dispersion with a solid content concentration of 2.0% by mass.

[0482] 300g of epoxy resin was added to 300g of the obtained dispersion. After stirring at 25°C for 1 hour, the mixture was dispersed five times at 150MPa using a high-pressure homogenizer (Yoshida Machinery Kogyo Co., Ltd., NanoVater L-ES). The resulting cellulose fiber dispersion immediately agglomerated and precipitated after the dispersion treatment, making it unsuitable for resin membrane fabrication.

[0483] Comparative Example 4

[0484] Except that no silane compound was used, the same treatment as in Example 5 above was performed to obtain the composition described in Table 4.

[0485] Reference Example 1

[0486] Except for the absence of cellulose fibers, the same treatment as in Example 1 above was performed to obtain the composition described in Table 3.

[0487] Experimental Example 1 (Evaluation of Dispersion)

[0488] The dispersibility of cellulose fibers with bonded modification groups was evaluated in the following manner.

[0489] Regarding Examples 1-2 and Comparative Examples 1-2, the "PGME dispersion of cellulose fibers with bonded modification groups" obtained as an intermediate in Preparation Example 2 was used as the evaluation object. Regarding Comparative Example 3, the "PGME dispersion of short-fiber anion-modified cellulose fibers" prepared as an intermediate was used as the evaluation object. Each was allowed to stand at room temperature for one day, and the presence or absence of precipitates was visually confirmed. Evaluations were conducted based on the following criteria. In cases where the evaluation result was A or B, the dispersibility was considered good, and the dispersibility was considered superior to that of the evaluation result A.

[0490] A: No precipitate was produced.

[0491] B: It has been confirmed that some precipitate has been produced.

[0492] F: The liquid components are completely separated from the solids, and all the solids precipitate.

[0493] nt: No evaluation performed.

[0494] Experimental Example 2 (Evaluation of Resin Membrane)

[0495] [Preparation of Resin Membranes]

[0496] Using a coating applicator (manufactured by TESTER SANGYO), a composition containing modified cellulose fibers and resin obtained in the various examples was applied to a copper foil to a coating thickness of 170 μm, and then cured by heating at 130°C for 2 hours, thereby producing a resin film.

[0497] [Determination of storage modulus]

[0498] Peel the resin film off the copper foil and cut a short strip sample with a width of 5 mm and a length of 40 mm.

[0499] Using a dynamic viscoelastic apparatus (manufactured by SII, "DMS6100"), under a nitrogen atmosphere, the temperature was increased from 30°C to 300°C at a frequency of 1 Hz, in a 1°C increment over 1 minute, and the storage modulus of the sample was measured in tensile mode with a clamping distance of 20 mm. The storage modulus values ​​at 30°C and 200°C are used.

[0500] The storage modulus (E') listed in Tables 3 and 4 are values ​​at 30°C or 200°C, in GPa. The higher the value, the better the strength; therefore, a higher storage modulus at high temperatures indicates better heat resistance.

[0501] [Determination of glass transition temperature (Tg)]

[0502] Peel the resin film off the copper foil and cut a short strip sample with a width of 5 mm and a length of 20 mm.

[0503] Using a dynamic viscoelastic apparatus (manufactured by SII, "DMS6100"), under a nitrogen atmosphere, the temperature was increased from 30°C to 300°C at a frequency of 1 Hz, in a 10°C increment over 1 minute, and measured in tensile mode. The peak temperature of tanδ was used as the glass transition point (Tg).

[0504] A high glass transition temperature (°C) indicates excellent heat resistance.

[0505] [Table 3]

[0506]

[0507] [Table 4]

[0508]

[0509] In Tables 3 and 4, "Silane compound amount relative to CNF" refers to the mass fraction of the (compounded) silane compound relative to 100 parts by mass of the cellulose fiber (CNF) portion of the cellulose fiber bonded with the modified group.

[0510] Details of the main components used in the above embodiments are as follows.

[0511] [Resin]

[0512] Epoxy resin (manufactured by Mitsubishi Chemical Corporation, JER828, epoxy equivalent = 184-194, weight average molecular weight = 370)

[0513] [Curing agent]

[0514] The product is made by crushing dicyandiamide (manufactured by Mitsubishi Chemical Co., Ltd.) using a small mixer (manufactured by Osaka Chemical Co., Ltd.).

[0515] [Curing Accelerator]

[0516] The product is made by pulverizing 3-(3,4-chlorophenyl)-1,1-dimethylurea (DCMU) (manufactured by Thermo Scientific) using a small blender (manufactured by Osaka Chemical Co., Ltd.).

[0517] [Silane compounds]

[0518] 3-Aminopropyltrimethoxysilane (abbreviated as "amino" in the table) (KBM-903 manufactured by Shin-Etsu Silicones)

[0519] n-Propyltrimethoxysilane (abbreviated as "propyl" in the table) (manufactured by Shin-Etsu Silicones, KBM-3033)

[0520] N-Phenylacetyl-3-aminopropyltrimethoxysilane (abbreviated as "N-phenyl" in the table) (manufactured by Shin-EtsuSilicones, KBM-573)

[0521] [other]

[0522] PGME: 1-Methoxy-2-propanol (manufactured by Daicel)

[0523] EO / PO amine: Methoxylated poly(ethylene oxide / propylene oxide)-2-propylamine (manufactured by HUNTSMAN, JEFFAMINE M2070, Mw=2000, EO:PO=4:1)

[0524] Industrial availability

[0525] The modified cellulose fiber of the present invention can be used in various molded product fields such as home appliance parts, electronic equipment, aerospace, civil engineering, automobiles, and vehicle applications.

Claims

1. A resin composition comprising the following components: Modified cellulose fibers are cellulose fibers bonded with silane compounds and modified with groups other than silanol groups; and Resin.

2. The resin composition according to claim 1, wherein, The silane compound is selected from one or more silane compounds chosen from chlorosilane compounds, alkoxysilane compounds, acetoxysilane compounds, and silanol compounds.

3. The resin composition according to claim 1 or 2, wherein, The amount of the silane compound is 50 parts by mass or more relative to 100 parts by mass of the cellulose fiber portion of the cellulose fiber bonded with modification groups other than silanol groups.

4. The resin composition according to any one of claims 1 to 3, wherein, The amount of modified cellulose in the resin composition is 4.0% by mass or more and 20% by mass or less.

5. The resin composition according to any one of claims 1 to 4, wherein, The amount of cellulose fiber in the resin composition is more than 0.1% by mass and less than 20% by mass.

6. The resin composition according to any one of claims 1 to 5, wherein, The resin content in the resin composition is 70% by mass or more and 95% by mass or less.

7. The resin composition according to any one of claims 1 to 6, wherein, The mass ratio of the amount of modified cellulose in the resin composition to the amount of resin, i.e., the amount of modified cellulose fiber / the amount of resin, is 5 / 95 or more and 20 / 80 or less.

8. The resin composition according to any one of claims 1 to 7, wherein, The mass ratio of the amount of cellulose fiber in the resin composition to the amount of resin, i.e., the amount of cellulose fiber / the amount of resin, is 0.1 / 99.9 or more and 20 / 80 or less.

9. A resin molded article comprising the resin composition according to any one of claims 1 to 8.

10. A method for manufacturing modified cellulose fibers, comprising the following steps: Step 1: A step of bonding a modifying group other than a silanol group to the ionic group of a cellulose fiber, thereby obtaining a cellulose fiber bonded with the modified group; and Step 2: A step of mixing cellulose fibers bonded with the modified group with one or more silane compounds selected from chlorosilane compounds, alkoxysilane compounds, acetoxysilane compounds, and silanol compounds; and The amount of the silane compound in step 2 is 50 parts by mass or more, relative to 100 parts by mass of the cellulose fiber portion of the cellulose fiber to which the modified group is bonded.

11. A method for manufacturing modified cellulose fibers, comprising the following steps: Step 3: A step of mixing cellulose fibers with ionic groups with one or more silane compounds selected from chlorosilane compounds, alkoxysilane compounds, acetoxysilane compounds, and silanol compounds to obtain cellulose fibers bonded with silane compounds; and Step 4: A step of bonding modifying groups other than silanol groups to the ionic groups of the cellulose fibers bonded with silane compounds, thereby obtaining modified cellulose fibers; and The amount of the silane compound in step 3 is 50 parts by mass or more, relative to 100 parts by mass of the cellulose fiber portion having the ionic group.

12. A modified cellulose fiber manufactured by the manufacturing method of claim 10 or 11.

13. A composition comprising the modified cellulose fiber of claim 12.

14. The composition according to claim 13, further comprising an organic solvent and / or a resin.

15. A resin additive comprising the modified cellulose fiber as described in claim 12.

16. The resin additive according to claim 15, further comprising an organic solvent.

17. A method for manufacturing a resin composition, comprising the following steps: Step 5: A step of bonding a modifying group other than a silanol group to the ionic group of a cellulose fiber, thereby obtaining a cellulose fiber bonded with the modified group; and Step 6: A step of mixing one or more silane compounds selected from chlorosilane compounds, alkoxysilane compounds, acetoxysilane compounds, and silanol compounds, cellulose fibers bonded with the modified group, and resin; and The amount of the silane compound in step 6 is 50 parts by mass or more, relative to 100 parts by mass of the cellulose fiber portion of the cellulose fiber to which the modified group is bonded.

18. A method for manufacturing a resin composition, comprising the following steps: Step 7: A step of mixing cellulose fibers with ionic groups with one or more silane compounds selected from chlorosilane compounds, alkoxysilane compounds, acetoxysilane compounds, and silanol compounds to obtain cellulose fibers bonded with silane compounds; and Step 8: A step of bonding a modification group other than a silanol group to the ionic group of the cellulose fiber bonded with the silane compound, thereby obtaining modified cellulose fiber. and The amount of the silane compound in step 7 is 50 parts by mass or more, relative to 100 parts by mass of the cellulose fiber portion having the ionic group.

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