JP2018145571A - Method for producing modified cellulose fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a modified cellulose fiber that shows excellent mechanical strength and toughness of a molding with a resin.SOLUTION: A method for producing a modified cellulose fiber includes a step of introducing one or more compound selected from an aromatic ring-containing alkylene oxide compound and an aromatic ring-containing glycidyl ether compound, into a cellulose raw material, through ether linkage, in the presence of a base, and then performing a finely dividing treatment. The modified cellulose fiber is one in which a specific substituent is bound to a cellulose fiber through ether linkage, to form a cellulose I type crystal structure.SELECTED DRAWING: None

Description

  The present invention relates to a method for producing a modified cellulose fiber.

  Conventionally, plastic materials derived from petroleum, which is a finite resource, have been widely used, but in recent years, technologies with less environmental impact have come to the spotlight. Materials using cellulose fibers have attracted attention.

  For example, U.S. Patent No. 6,057,049, specific surface substitutions wherein the hydroxyl functional group is etherified with an organic compound for the purpose of providing cellulose microfibrils with significantly reduced hydrophilicity while retaining advantageous mechanical properties. Cellulose microfibrils having a degree are disclosed.

JP-T-2002-524618

  However, the cellulose microfibrils of Patent Document 1 are not sufficiently satisfactory with respect to the mechanical strength and toughness of a molded product produced by being combined with a resin.

  The present invention relates to a method for producing a modified cellulose fiber excellent in mechanical strength and toughness in a molded body with a resin.

The present invention relates to the following [1] to [6].
[1] After introducing one or two or more compounds selected from an aromatic ring-containing alkylene oxide compound and an aromatic ring-containing glycidyl ether compound through an ether bond in the presence of a base into a cellulose-based raw material, a refinement treatment A method for producing a modified cellulose fiber, comprising:
The modified cellulose fiber has one or more substituents selected from the substituent represented by the following general formula (1) and the substituent represented by the following general formula (2) via an ether bond. A method for producing a modified cellulose fiber, which is bonded to a cellulose fiber and has a cellulose I-type crystal structure.
—CH ₂ —CH (OH) —R ₁ (1)
—CH ₂ —CH (OH) —CH ₂ — (OA) _n —O—R ₁ (2)
[Wherein, R ₁ in the general formula (1) and the general formula (2) each independently represents a functional group having 6 to 30 carbon atoms having at least one aromatic ring, and n in the general formula (2) Represents a number of 0 to 50, and A represents a linear or branched divalent saturated hydrocarbon group having 1 to 6 carbon atoms. ]
[2] A resin composition comprising a modified cellulose fiber obtained by the production method according to [1] and a resin.
[3] A modified cellulose fiber having an average fiber diameter of 5 μm or more, which is selected from the substituent represented by the following general formula (1) and the substituent represented by the following general formula (2) or A modified cellulose fiber having two or more types of substituents bonded to a cellulose fiber through an ether bond and having a cellulose I-type crystal structure.
—CH ₂ —CH (OH) —R ₁ (1)
—CH ₂ —CH (OH) —CH ₂ — (OA) _n —O—R ₁ (2)
[Wherein, R ₁ in the general formula (1) and the general formula (2) each independently represents a functional group having 6 to 30 carbon atoms having at least one aromatic ring, and n in the general formula (2) Represents a number of 0 to 50, and A represents a linear or branched divalent saturated hydrocarbon group having 1 to 6 carbon atoms. ]
[4] One or more substituents selected from the substituent represented by the following general formula (1) and the substituent represented by the following general formula (2), and the following general formula (3) And one or more substituents selected from the substituent represented by the following general formula (4) are bonded to the cellulose fiber via an ether bond and have a cellulose I-type crystal structure. Cellulose fiber.
—CH ₂ —CH (OH) —R ₁ (1)
—CH ₂ —CH (OH) —CH ₂ — (OA) _n —O—R ₁ (2)
[Wherein, R ₁ in the general formula (1) and the general formula (2) each independently represents a functional group having 6 to 30 carbon atoms having at least one aromatic ring, and n in the general formula (2) Represents a number of 0 to 50, and A represents a linear or branched divalent saturated hydrocarbon group having 1 to 6 carbon atoms. ]
—CH ₂ —CH (OH) —R ₂ (3)
—CH ₂ —CH (OH) —CH ₂ — (OA) _n —O—R ₂ (4)
[Wherein, R ₂ in general formula (3) and general formula (4) each independently represents hydrogen or a linear or branched alkyl group having 1 to 20 carbon atoms, and n in general formula (4) Represents a number of 0 to 50, and A represents a linear or branched divalent saturated hydrocarbon group having 1 to 6 carbon atoms. ]
[5] One or more compounds selected from an aromatic ring-containing alkylene oxide compound and an aromatic ring-containing glycidyl ether compound in the presence of a base with respect to a cellulose-based raw material, and an alkylene oxide compound represented by the general formula (3A) And a method for producing a modified cellulose fiber, wherein one or two or more compounds selected from glycidyl ether compounds represented by the general formula (4A) are introduced via an ether bond,
The modified cellulose fiber is one or more substituents selected from the substituent represented by the following general formula (1) and the substituent represented by the following general formula (2), and the following general formula ( 1 type or 2 or more types of substituents chosen from the substituent represented by 3) and the substituent represented by following General formula (4) couple | bonded with a cellulose fiber via an ether bond, and cellulose I type crystal structure The manufacturing method of the modified cellulose fiber which has this.
—CH ₂ —CH (OH) —R ₁ (1)
—CH ₂ —CH (OH) —CH ₂ — (OA) _n —O—R ₁ (2)
[Wherein, R ₁ in the general formula (1) and the general formula (2) each independently represents a functional group having 6 to 30 carbon atoms having at least one aromatic ring, and n in the general formula (2) Represents a number of 0 to 50, and A represents a linear or branched divalent saturated hydrocarbon group having 1 to 6 carbon atoms. ]
—CH ₂ —CH (OH) —R ₂ (3)
—CH ₂ —CH (OH) —CH ₂ — (OA) _n —O—R ₂ (4)

[Wherein, R ₂ in the general formulas (3), (3A), (4) and (4A) each independently represents hydrogen or a linear or branched alkyl group having 1 to 20 carbon atoms; In formulas (4) and (4A), n represents a number of 0 to 50, and A represents a linear or branched divalent saturated hydrocarbon group having 1 to 6 carbon atoms. ]
[6] A resin composition comprising the modified cellulose fiber according to [4] or the modified cellulose fiber obtained by the production method according to [5] and a resin.

  According to the production method of the present invention, it is possible to provide a method for producing a modified cellulose fiber excellent in mechanical strength and toughness in a molded body with a resin.

  The molded body using the modified cellulose fiber produced by the production method of the present invention surprisingly exhibits excellent mechanical strength and toughness. Since there is no prior art that suggests such effects, it is difficult for those skilled in the art to predict the effects.

[Method for producing modified cellulose fiber]
Specifically, the production method of the present invention includes the following two embodiments. A 1st aspect introduce | transduces the 1 type, or 2 or more types of compound chosen from an aromatic ring containing alkylene oxide compound and an aromatic ring containing glycidyl ether compound through an ether bond with respect to a cellulose raw material in the presence of a base, It is the manufacturing method of the modified cellulose fiber which performs a refinement | miniaturization process. And a 2nd aspect is shown with the general formula (3A) with 1 type, or 2 or more types of compounds chosen from an aromatic ring containing alkylene oxide compound and an aromatic ring containing glycidyl ether compound with respect to a cellulose raw material in the presence of a base. This is a method for producing a modified cellulose fiber, wherein one or two or more compounds selected from an alkylene oxide compound and a glycidyl ether compound represented by formula (4A) are introduced via an ether bond. In the present specification, “bonded via an ether bond” means a state in which the modifying group reacts with a hydroxyl group on the surface of the cellulose fiber to form an ether bond. Further, in the present specification, a compound for introducing a predetermined substituent into a cellulosic raw material via an ether bond is referred to as an etherifying agent.

[Method for Producing Modified Cellulose Fiber of First Aspect]
The modified cellulose fiber produced by the method of the first aspect is one or more selected from the substituent represented by the following general formula (1) and the substituent represented by the following general formula (2). Are bonded to the cellulose fiber via an ether bond and have a cellulose I-type crystal structure.
—CH ₂ —CH (OH) —R ₁ (1)
—CH ₂ —CH (OH) —CH ₂ — (OA) _n —O—R ₁ (2)
[Wherein, R ₁ in the general formula (1) and the general formula (2) each independently represents a functional group having 6 to 30 carbon atoms having at least one aromatic ring, and n in the general formula (2) Represents a number of 0 to 50, and A represents a linear or branched divalent saturated hydrocarbon group having 1 to 6 carbon atoms. ]

(Cellulosic material)
The cellulosic raw material used in the present invention is not particularly limited, and is based on woody (coniferous and broadleaf), herbaceous (grass, mallow, legumes, non-woody raw materials of palms), pulp (Such as cotton linter pulp obtained from fibers around cotton seeds), paper (newspaper, cardboard, magazines, fine paper, etc.) and the like. Of these, woody and herbaceous are preferred from the viewpoints of availability and cost.

  The shape of the cellulosic raw material is not particularly limited, but is preferably a fiber, powder, sphere, chip, or flake from the viewpoint of handleability. Moreover, these mixtures may be sufficient.

  In addition, the cellulosic raw material can be subjected in advance to at least one pretreatment selected from biochemical treatment, chemical treatment, and mechanical treatment from the viewpoint of handleability and the like. The biochemical treatment is not particularly limited to the drug used, and examples thereof include treatment using an enzyme such as endoglucanase, exoglucanase, or betaglucosidase. The chemical treatment is not particularly limited as to the chemical used, and examples thereof include acid treatment with hydrochloric acid and sulfuric acid, and oxidation treatment with hydrogen peroxide and ozone. As the mechanical treatment, there is no particular limitation on the machine to be used and the treatment conditions, for example, a high pressure compression roll mill, a roll mill such as a roll rotating mill, a vertical roller mill such as a ring roller mill, a roller race mill or a ball race mill, Rolling ball mill, vibrating ball mill, vibrating rod mill, vibrating tube mill, planetary ball mill, centrifugal fluidizing mill and other container driven medium mills, tower type grinder, stirring tank type mill, flow tank type mill or annular type mill, etc. Condensation shearing mills such as type mills, high-speed centrifugal roller mills and ong mills, mortars, millstones, mass colloiders, fret mills, edge runner mills and other grinding machines, knife mills, pin mills, cutter mills and the like.

  In the above mechanical treatment, water, ethanol, isopropyl alcohol, t-butyl alcohol, toluene, xylene and other solvents, phthalic acid-based, adipic acid-based, trimellitic acid-based plasticizers, urea and alkali (earth) ) It is possible to promote shape change by mechanical treatment by adding auxiliary agents such as metal hydroxides and hydrogen bond inhibitors such as amine compounds. By adding the shape change in this manner, the handling property of the cellulose-based raw material is improved, the introduction of the substituent is improved, and the physical properties of the resulting modified cellulose fiber can be improved. The amount of the additive aid used varies depending on the additive aid used, the mechanical processing technique used, and the like, but from the viewpoint of expressing the effect of promoting the shape change, preferably 5 parts by mass or more with respect to 100 parts by mass of the raw material. More preferably, it is 10 parts by mass or more, more preferably 20 parts by mass or more, and preferably 10,000 parts by mass or less, more preferably 5000 parts by mass, from the viewpoint of expressing the effect of promoting shape change and economical efficiency. Part or less, more preferably 3000 parts by weight or less.

  The average fiber diameter of the cellulosic raw material is not particularly limited, but is preferably 5 μm or more, more preferably 7 μm or more, still more preferably 10 μm or more, and still more preferably 15 μm or more from the viewpoints of handleability and cost. In addition, the upper limit is not particularly set, but from the viewpoint of handleability, it is preferably 10,000 μm or less, more preferably 5,000 μm or less, still more preferably 1,000 μm or less, still more preferably 500 μm or less, and even more preferably 100 μm or less. It is.

  The average fiber diameter of the cellulosic raw material is, for example, stirring the completely dried cellulose fiber in ion-exchanged water using a household mixer etc. to dissolve the fiber, and then adding ion-exchanged water and stirring it uniformly. A method of analyzing a part of the obtained aqueous dispersion with “Kajaani Fiber Lab” manufactured by Metso Automation Co., Ltd. can be mentioned. By this method, a fiber diameter having an average fiber diameter of micro order can be measured. The detailed measurement method is as described in the examples.

  The composition of the cellulosic raw material is not particularly limited, but the cellulose content in the cellulosic raw material is preferably 30% by mass or more, more preferably 50% by mass or more, and still more preferably 70% by mass from the viewpoint of obtaining cellulose fibers. From the viewpoint of availability, it is preferably 99% by mass or less, more preferably 98% by mass or less, still more preferably 95% by mass or less, and still more preferably 90% by mass or less. Here, the cellulose content in the cellulosic raw material is the cellulose content in the remaining components excluding moisture in the cellulosic raw material.

  Further, the moisture content in the cellulosic material is preferably as small as possible from the viewpoint of handleability. For example, it is preferably 50% by mass or less, more preferably 40% by mass or less, still more preferably 30% by mass or less, still more preferably 20% by mass or less, still more preferably 10% by mass or less.

(base)
The introduction of the substituent is performed in the presence of a base. Although there is no restriction | limiting in particular as a base used here, From a viewpoint of advancing etherification reaction, an alkali metal hydroxide, an alkaline-earth metal hydroxide, a 1-3 tertiary amine, a quaternary ammonium salt, imidazole, and One or more selected from the group consisting of derivatives thereof, pyridine and derivatives thereof, and alkoxides are preferred.

  Examples of the alkali metal hydroxide and alkaline earth metal hydroxide include sodium hydroxide, potassium hydroxide, lithium hydroxide, calcium hydroxide, and barium hydroxide.

  The primary to secondary amines are primary amines, secondary amines, and tertiary amines. Specific examples include ethylenediamine, diethylamine, proline, N, N, N ′, N′-tetramethylethylenediamine, N, N, N ′, N′-tetramethyl-1,3-propanediamine, N, N, N ′, N′-tetramethyl-1,6-hexanediamine, tris (3-dimethylaminopropyl) amine, N, N-dimethylcyclohexylamine, triethylamine and the like can be mentioned.

  Quaternary ammonium salts include tetrabutylammonium hydroxide, tetrabutylammonium chloride, tetrabutylammonium fluoride, tetrabutylammonium bromide, tetraethylammonium hydroxide, tetraethylammonium chloride, tetraethylammonium fluoride, tetraethylammonium bromide, water Examples thereof include tetramethylammonium oxide, tetramethylammonium chloride, tetramethylammonium fluoride, and tetramethylammonium bromide.

  Examples of imidazole and derivatives thereof include 1-methylimidazole, 3-aminopropylimidazole, carbonyldiimidazole and the like.

  Examples of pyridine and derivatives thereof include N, N-dimethyl-4-aminopyridine and picoline.

  Examples of the alkoxide include sodium methoxide, sodium ethoxide, potassium t-butoxide and the like.

  The amount of the base is preferably 0.01 equivalents or more, more preferably 0.05 equivalents or more, still more preferably 0.1 from the viewpoint of allowing the etherification reaction to proceed with respect to the anhydroglucose unit of the cellulosic raw material. Equal amount or more, more preferably 0.2 equivalent or more, and from the viewpoint of production cost, it is preferably 10 equivalents or less, more preferably 8 equivalents or less, still more preferably 5 equivalents or less, still more preferably 3 etc. Less than the amount. The anhydroglucose unit is abbreviated as “AGU”. AGU is calculated on the assumption that all cellulosic materials are composed of anhydroglucose units.

  You may perform mixing of a cellulose raw material and a base in presence of a solvent. The solvent is not particularly limited, and examples thereof include water, isopropanol, t-butanol, dimethylformamide, toluene, methyl isobutyl ketone, acetonitrile, dimethyl sulfoxide, dimethylacetamide, 1,3-dimethyl-2-imidazolidinone, hexane, 1,4-dioxane, and mixtures thereof.

  The mixing of the cellulosic raw material and the base is not particularly limited as long as it can be uniformly mixed.

(Aromatic ring-containing alkylene oxide compound and aromatic ring-containing glycidyl ether compound)
Next, one or more compounds selected from an aromatic ring-containing alkylene oxide compound and an aromatic ring-containing glycidyl ether compound are added to the cellulose-based raw material and base mixture obtained above, and the substituent is added. Bond to cellulose fiber.

  The aromatic ring-containing alkylene oxide compound is used for bonding the substituent represented by the general formula (1) to the cellulose fiber. Examples of the aromatic ring-containing alkylene oxide compound include an alkylene oxide compound having an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, or a heteroaromatic ring having 6 to 20 carbon atoms. Specific examples include styrene oxide and derivatives thereof. Among these, styrene oxide is preferable from the viewpoints of availability and reactivity.

  The aromatic ring-containing glycidyl ether compound is used for bonding the substituent represented by the general formula (2) to the cellulose fiber. Examples of the aromatic ring-containing glycidyl ether compound include glycidyl ether compounds having an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, or a heteroaromatic ring having 6 to 20 carbon atoms. Specific examples include phenyl glycidyl ether, trityl glycidyl ether, benzyl glycidyl ether, and derivatives thereof. Among these, phenyl glycidyl ether and trityl glycidyl ether are preferable from the viewpoint of availability and reactivity, and phenyl glycidyl ether is more preferable.

  The amount of the aromatic ring-containing alkylene oxide compound and the aromatic ring-containing glycidyl ether compound can be determined by the desired introduction rate of substituents in the resulting modified cellulose fiber. For example, from the viewpoint of the mechanical strength of the obtained molded product, the amount of such a compound is preferably 10.0 equivalents or less, more preferably 8.0, etc. with respect to 1 unit of anhydroglucose unit of the cellulosic raw material. Or less, more preferably 7.0 equivalents or less, still more preferably 6.0 equivalents or less, preferably 0.02 equivalents or more, more preferably 0.05 equivalents or more, still more preferably 0.1 equivalents. More preferably, it is 0.3 equivalent or more, more preferably 1.0 equivalent or more. Here, when using both an aromatic-ring containing alkylene oxide compound and an aromatic-ring containing glycidyl ether compound, the quantity of a compound is a total amount of both.

(Ether reaction)
The ether reaction between the compound and the cellulose-based raw material can be carried out by mixing both in the presence of a solvent. There is no restriction | limiting in particular as a solvent, The said solvent illustrated that it can be used when a base is made to exist can be used.

  The amount of the solvent used is not generally determined depending on the type of the cellulose-based raw material or the compound for introducing the substituent, but is preferably 30 parts by mass with respect to 100 parts by mass of the cellulose-based raw material from the viewpoint of reactivity. Or more, more preferably 50 parts by mass or more, still more preferably 75 parts by mass or more, further preferably 100 parts by mass or more, further preferably 200 parts by mass or more, and from the viewpoint of productivity, preferably 10,000 parts by mass or less. More preferably, it is 7,500 mass parts or less, More preferably, it is 5,000 mass parts or less, More preferably, it is 2,500 mass parts or less, More preferably, it is 1,000 mass parts or less.

  The mixing conditions are not particularly limited as long as the cellulose-based raw material and the compound for introducing a substituent are uniformly mixed and the reaction can proceed sufficiently, whether or not continuous mixing is performed. Good. In the case of using a relatively large reaction vessel exceeding 1 L, stirring may be appropriately performed from the viewpoint of controlling the reaction temperature.

  The reaction temperature is not determined unconditionally depending on the type of the cellulose-based raw material and the compound for introducing the substituent and the target introduction rate, but is preferably 30 ° C. or more, more preferably from the viewpoint of improving the reactivity. 35 ° C or higher, more preferably 40 ° C or higher. From the viewpoint of suppressing thermal decomposition, it is preferably 120 ° C or lower, more preferably 110 ° C or lower, still more preferably 100 ° C or lower, still more preferably 90 ° C or lower, still more preferably. Is 80 ° C. or lower, more preferably 70 ° C. or lower.

  The reaction time is not unconditionally determined depending on the type of the cellulosic raw material and the compound for introducing the substituent and the target introduction rate, but from the viewpoint of reactivity, preferably 0.1 hour or more, more preferably 0.5 hours or more, more preferably 1 hour or more, more preferably 3 hours or more, further preferably 6 hours or more, more preferably 10 hours or more. From the viewpoint of productivity, preferably 60 hours or less, more preferably Is 48 hours or less, more preferably 36 hours or less.

  After the reaction, an appropriate post-treatment can be performed to remove unreacted compounds, bases and the like. As the post-treatment method, for example, an unreacted base can be neutralized with an acid (organic acid, inorganic acid, etc.), and then washed with a solvent in which the unreacted compound or base dissolves. If desired, further drying (such as vacuum drying) may be performed.

  Thus, the modified cellulose before the refining treatment in which one or more substituents selected from the substituent represented by the general formula (1) and the substituent represented by the general formula (2) are introduced. Fiber is obtained.

[Modified cellulose fiber before refinement]
The modified cellulose fiber before the refining treatment in the method of the first aspect is one or more selected from the substituent represented by the general formula (1) and the substituent represented by the general formula (2). Are bonded to the cellulose fiber via an ether bond and have a cellulose I-type crystal structure, and the specific structure can be represented, for example, by the general formula (5).

[Wherein, R is the same or different and represents a substituent selected from hydrogen and substituents represented by the general formulas (1) to (2); m is preferably an integer of 20 or more and 3000 or less; Except where all R are simultaneously hydrogen. ]

  M in the general formula (5) is preferably an integer of 20 or more and 3000 or less, and more preferably an integer of 100 or more and 2000 or less from the viewpoint of mechanical strength and toughness expression.

The substituent represented by the general formula (1) and the substituent represented by the general formula (2) in the general formula (5) are as follows. In addition, even if it is a case where the substituent represented by General formula (1) and the substituent represented by General formula (2) in a modified cellulose fiber are any one, in each substituent, the same substituent Even two or more of them may be introduced in combination.
—CH ₂ —CH (OH) —R ₁ (1)
—CH ₂ —CH (OH) —CH ₂ — (OA) _n —O—R ₁ (2)
[Wherein, R ₁ in the general formula (1) and the general formula (2) each independently represents a functional group having 6 to 30 carbon atoms having at least one aromatic ring, and n in the general formula (2) Represents a number of 0 to 50, and A represents a linear or branched divalent saturated hydrocarbon group having 1 to 6 carbon atoms. ]

R ₁ in the general formula (1) and the general formula (2) is a functional group having 6 to 30 carbon atoms and having at least one aromatic ring. The carbon number of R ₁ is preferably 6 or more from the viewpoint of mechanical strength and toughness expression, and is preferably 25 or less, more preferably 20 or less from the viewpoint of reactivity and availability. Specific examples of R ₁ include phenyl groups, trityl groups, naphthyl groups, aryl groups such as tolyl groups and xylyl groups, and aralkyl groups such as benzyl groups and phenethyl groups.

  N in the general formula (2) represents the number of added moles of alkylene oxide. n is a number of 0 or more and 50 or less, and is preferably 0 from the viewpoint of availability and cost, and from the same viewpoint, preferably 40 or less, more preferably 30 or less, still more preferably 20 or less, and still more preferably. Is 15 or less.

  A in the general formula (2) is a linear or branched divalent saturated hydrocarbon group having 1 to 6 carbon atoms, and forms an oxyalkylene group with an adjacent oxygen atom. The carbon number of A is 1 or more and 6 or less, but from the viewpoint of availability and cost, it is preferably 2 or more, and from the same viewpoint, it is preferably 4 or less, more preferably 3 or less. Specific examples include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, and a hexylene group. Among them, an ethylene group and a propylene group are preferable, and an ethylene group is more preferable.

  As a combination of A and n in the general formula (2), from the viewpoint of availability and cost, A is preferably a linear or branched divalent saturated hydrocarbon group having 2 to 3 carbon atoms, and n is A combination of 0 or more and 20 or less, more preferably A is a linear or branched divalent saturated hydrocarbon group having 2 or more and 3 or less carbon atoms, and n is a combination of numbers of 0 or more and 15 or less. .

(Average fiber diameter)
The average fiber diameter of the modified cellulose fiber before the refining treatment in the method of the first aspect is preferably 5 μm or more regardless of the type of the substituent. From the viewpoints of handleability, availability, and cost, it is more preferably 7 μm or more, further preferably 10 μm or more, and further preferably 15 μm or more. In addition, the upper limit is not particularly set, but from the viewpoint of handleability, it is preferably 10,000 μm or less, more preferably 5,000 μm or less, still more preferably 1,000 μm or less, still more preferably 500 μm or less, and even more preferably 100 μm or less. It is. In addition, the average fiber diameter of the modified cellulose fiber can be measured in the same manner as the above-described cellulose raw material. Details are as described in the examples.

(Crystallinity)
The crystallinity of the modified cellulose fiber is preferably 10% or more, more preferably 15% or more, and still more preferably 20% or more from the viewpoint of strength development. Moreover, from a viewpoint of raw material availability, Preferably it is 90% or less, More preferably, it is 85% or less, More preferably, it is 80% or less, More preferably, it is 75% or less. In the present specification, the crystallinity of cellulose is a cellulose I-type crystallinity calculated from a diffraction intensity value obtained by an X-ray diffraction method, and can be measured according to a method described in Examples described later. Cellulose type I is a crystalline form of natural cellulose, and cellulose type I crystallinity means the proportion of the total amount of crystal region in the whole cellulose. The presence or absence of the cellulose type I crystal structure can be determined by a peak at 2θ = 22.6 ° in the X-ray diffraction measurement.

(Introduction rate)
In the modified cellulose fiber before the refinement treatment in the method of the first aspect, the substituent represented by the general formula (1) and / or the substitution represented by the general formula (2) with respect to 1 mol of anhydroglucose unit of cellulose. The group introduction ratio (MS) is preferably 0.001 mol or more, more preferably 0.005 mol or more, and further preferably 0.03 mol or more, from the viewpoint of mechanical strength and toughness expression. In addition, it has a cellulose type I crystal structure, and from the viewpoint of mechanical strength and toughness expression, it is preferably 1.5 mol or less, more preferably 1.3 mol or less, still more preferably 1.0 mol or less, still more preferably 0.8 mol or less, more preferably 0.6 mol or less, and still more preferably 0.5 mol or less. Here, when both the substituent represented by the general formula (1) and the substituent represented by the general formula (2) are introduced, it means the total introduction molar ratio. In the present specification, the introduction rate can be measured according to the method described in the examples described later, and may be described as the introduction molar ratio or the modification rate.

(Miniaturization processing)
The method for producing a modified cellulose fiber according to the first aspect includes a step of refining the modified cellulose fiber before the refining treatment. The refinement process can be performed by a known refinement process method. For example, when obtaining finely modified cellulose fibers having an average fiber diameter of 1 nm or more and 500 nm or less, it is refined by performing a treatment using a grinding machine such as a mass collider or a treatment using a high-pressure homogenizer in an organic solvent. be able to. Alternatively, as described later, the resin and the modified cellulose fiber can be refined simultaneously with mixing. In addition, the modified cellulose fiber in the present invention is subjected to the same treatment as the pretreatment performed on the cellulose-based raw material after the reaction, for example, in the form of chips or flakes. You may make it into a powder form. The shape change caused by such treatment can improve the efficiency of the refinement treatment when the resulting modified cellulose fiber of the present invention is refined in an organic solvent or a resin composition. In the present specification, from the viewpoint of distinguishing from the modified cellulose fiber before the refinement treatment, the modified cellulose fiber after the refinement treatment may be referred to as “finely modified cellulose fiber”.

  Although it does not specifically limit as an organic solvent used for the refinement | miniaturization process at the time of obtaining the fine modified cellulose fiber whose average fiber diameter is 1 nm or more and 500 nm or less, For example, C1-C6, such as methanol, ethanol, a propanol, Preferably Alcohol having 1 to 3 carbon atoms; Ketone having 3 to 6 carbon atoms such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; Linear or branched saturated hydrocarbon or unsaturated hydrocarbon having 1 to 6 carbon atoms; benzene, toluene, and the like Aromatic hydrocarbons; halogenated hydrocarbons such as methylene chloride and chloroform; lower alkyl ethers having 2 to 5 carbon atoms; N, N-dimethylformamide (DMF), N, N-dimethylacetamide, dimethyl sulfoxide, and succinic acid Examples include polar solvents such as diesters with triethylene glycol monomethyl ether It is. These can be used alone or in admixture of two or more, but from the viewpoint of the operability of the refinement treatment, alcohols having 1 to 6 carbon atoms, ketones having 3 to 6 carbon atoms, and 2 to 5 carbon atoms. Preferred are lower alkyl ethers, N, N-dimethylformamide, succinic acid methyltriglycol diester, toluene and the like. The amount of the solvent used is not particularly limited as long as it is an effective amount capable of dispersing the modified cellulose fiber, but is preferably 1 mass times or more, more preferably 2 mass times or more, preferably with respect to the modified cellulose fiber. Is more preferably 500 mass times or less, more preferably 200 mass times or less.

  In addition to the high-pressure homogenizer, a known disperser is preferably used as an apparatus used in the miniaturization process. For example, a disaggregator, a beater, a low pressure homogenizer, a grinder, a mass collider, a cutter mill, a ball mill, a jet mill, a short screw extruder, a twin screw extruder, an ultrasonic stirrer, a household juicer mixer, and the like can be used. Further, the solid content concentration of the modified cellulose fiber in the refining treatment is preferably 50% by mass or less.

  The average fiber diameter of the refined modified cellulose fiber may be, for example, about 1 to 500 nm, and is preferably 3 nm or more, more preferably 10 nm or more, and still more preferably 20 nm from the viewpoints of handleability, availability, and cost. From the viewpoint of mechanical strength and toughness expression, it is preferably 300 nm or less, more preferably 200 nm or less, still more preferably 150 nm or less, and still more preferably 120 nm or less.

  Thus, the finely modified cellulose fiber produced by the method of the first aspect is obtained.

[Fine modified cellulose fiber in the first embodiment]
The finely modified cellulose fiber in the method of the first aspect is a substituent represented by the general formula (1) and a substitution represented by the general formula (2), similarly to the above-described modified cellulose fiber before the refinement treatment. One or two or more substituents selected from the group are bonded to the cellulose fiber via an ether bond and have a cellulose I-type crystal structure. The specific structure is, for example, the above general formula (5) Can be shown.

(Average fiber diameter)
The average fiber diameter of the finely modified cellulose fibers in the first aspect is preferably nano-order regardless of the type of substituent.

  The average fiber diameter of the finely modified cellulose fiber is preferably 1 nm or more, more preferably 3 nm or more, still more preferably 10 nm or more, and further preferably 20 nm or more from the viewpoints of handleability, availability, and cost. From the viewpoint of mechanical strength and toughness expression, it is preferably 500 nm or less, more preferably 300 nm or less, still more preferably 200 nm or less, still more preferably 150 nm or less, and still more preferably 120 nm or less. In the present specification, the average fiber diameter of the finely modified cellulose fibers can be measured according to the following method.

  Specifically, an atomic force microscope (AFM, Nanoscope III Tapping mode AFM) was prepared by using, as an observation sample, a dispersion obtained by performing the micronization treatment by dropping it on mica (mica) and drying it. The measurement can be carried out using a digital instrument (manufactured by Nanosensors, Point Probe (NCH)). In general, the smallest unit of cellulose nanofibers prepared from higher plants is a 6 × 6 molecular chain packed in a nearly square shape, so the height analyzed by AFM images is regarded as the fiber width. Can do. The detailed measurement method is as described in the examples.

  In addition, since the crystallinity of the modified cellulose fiber, the introduction rate of substituents, and the like are hardly affected by the refinement treatment, these properties are the same as those of the modified cellulose fiber before the refinement treatment.

[Method for Producing Modified Cellulose Fiber of Second Aspect]
The modified cellulose fiber produced by the method of this embodiment is one or more kinds of substituents selected from the substituent represented by the following general formula (1) and the substituent represented by the following general formula (2). 1 type, or 2 or more types of substituents chosen from the substituent represented by the following general formula (3) and the following general formula (4) are bonded to the cellulose fiber via an ether bond And has a cellulose I-type crystal structure.
—CH ₂ —CH (OH) —R ₁ (1)
—CH ₂ —CH (OH) —CH ₂ — (OA) _n —O—R ₁ (2)
[Wherein, R ₁ in the general formula (1) and the general formula (2) each independently represents a functional group having 6 to 30 carbon atoms having at least one aromatic ring, and n in the general formula (2) Represents a number of 0 to 50, and A represents a linear or branched divalent saturated hydrocarbon group having 1 to 6 carbon atoms. ]
—CH ₂ —CH (OH) —R ₂ (3)
—CH ₂ —CH (OH) —CH ₂ — (OA) _n —O—R ₂ (4)
[Wherein, R ₂ in general formula (3) and general formula (4) each independently represents hydrogen or a linear or branched alkyl group having 1 to 20 carbon atoms, and n in general formula (4) Represents a number of 0 to 50, and A represents a linear or branched divalent saturated hydrocarbon group having 1 to 6 carbon atoms. ]

R ₁ in general formula (1) and general formula (2) is the same as in the first embodiment.

Furthermore, R ₂ in the general formulas (3) and (4) is hydrogen or a linear or branched alkyl group having 1 to 20 carbon atoms. The number of carbon atoms of the alkyl group is preferably 3 or more, more preferably 6 or more, still more preferably 10 or more from the viewpoint of mechanical strength or toughness expression, and preferably 25 or less, more preferably from the viewpoint of reactivity and availability. 20 or less. Specifically, methyl, ethyl, propyl, isopropyl, butyl, pentyl, hexyl, heptyl, octyl, 2-ethylhexyl, nonyl, decyl, undecyl, dodecyl, hexadecyl Group, octadecyl group, isostearyl group, icosyl group and the like.

  N in the general formula (4) represents the number of added moles of alkylene oxide. n is a number of 0 or more and 50 or less, preferably 0 from the viewpoint of availability and cost, and preferably 40 or less from the same viewpoint and from the viewpoint of the mechanical strength and toughness expression of the resulting resin composition. More preferably, it is 30 or less, More preferably, it is 20 or less, More preferably, it is 15 or less, More preferably, it is 10 or less, More preferably, it is 5 or less.

  A in the general formula (4) is a linear or branched divalent saturated hydrocarbon group having 1 to 6 carbon atoms and forms an oxyalkylene group with an adjacent oxygen atom. The carbon number of A is 1 or more and 6 or less, but from the viewpoint of availability and cost, it is preferably 2 or more, and from the same viewpoint, it is preferably 4 or less, more preferably 3 or less. Specific examples include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, and a hexylene group. Among them, an ethylene group and a propylene group are preferable, and an ethylene group is more preferable.

  As a combination of A and n in the general formula (4), from the viewpoint of availability and cost, A is preferably a linear or branched divalent saturated hydrocarbon group having 2 to 3 carbon atoms, and n is A combination of 0 or more and 20 or less, more preferably A is a linear or branched divalent saturated hydrocarbon group having 2 or more and 3 or less carbon atoms, and n is a combination of numbers of 0 or more and 15 or less. .

  The introduction of the substituent can be carried out according to a known method without any particular limitation. Specifically, one or more compounds selected from an aromatic ring-containing alkylene oxide compound and an aromatic ring-containing glycidyl ether compound (referred to as “(b) compound”) in the presence of a base with respect to the cellulose-based raw material. And one or more compounds selected from an alkylene oxide compound represented by the following general formula (3A) and a glycidyl ether compound represented by the following general formula (4A) (referred to as “(a) compound”). May be introduced simultaneously or separately via an ether bond. Here, the introduction of these compounds is “simultaneously or separately” means that in this embodiment, the order of introduction of the compounds is not particularly limited. For example, the introduction of the compounds (a) and (b) Or (b) compound may be introduced after compound (a) is introduced first, or (a) compound may be introduced after compound (b) is introduced first. Means. In this embodiment, from the viewpoint of the mechanical strength and toughness expression of the obtained resin composition, a method of introducing the compound (a) after introducing the compound (b) is preferable. Hereinafter, the details will be described by taking such a method as an example.

  (B) As the modified cellulose fiber into which the compound has been previously introduced, those produced in the above first embodiment can be used regardless of the presence or absence of the refinement treatment.

  As a compound for introducing the substituent represented by the general formula (3), for example, an alkylene oxide compound represented by the general formula (3A) is preferable. As such a compound, one prepared according to a known technique may be used, or a commercially available product may be used. The total carbon number of the compound is 2 or more, preferably 3 or more, more preferably 4 or more, from the viewpoint of the mechanical strength and toughness expression of the resulting resin composition, and 22 or less from the same viewpoint. Preferably, it is 18 or less, more preferably 14 or less, and still more preferably 12 or less.

[Wherein, R ₂ represents hydrogen or a linear or branched alkyl group having 1 to 20 carbon atoms. ]

The carbon number and specific examples of the alkyl group represented by R ₂ in the general formula (3A) are the same as R ₂ in the general formula (3).

  Specific examples of the compound represented by the general formula (3A) include propylene oxide, butylene oxide, 1,2-epoxyhexane, 1,2-epoxyoctane, 1,2-epoxydecane, 1,2-epoxydodecane, , 2-epoxytetradecane, 1,2-epoxyoctadecane and the like.

  As a compound for introducing the substituent represented by the general formula (4), for example, a glycidyl ether compound represented by the general formula (4A) is preferable. As such a compound, one prepared according to a known technique may be used, or a commercially available product may be used. The total number of carbon atoms of the compound is 4 or more, preferably 5 or more, more preferably 6 or more, and still more preferably 10 or more, from the viewpoint of the mechanical strength and toughness expression of the obtained resin composition. From the viewpoint of the mechanical strength and toughness expression of the obtained resin composition, it is 100 or less, preferably 75 or less, more preferably 50 or less, and still more preferably 25 or less.

[Wherein R ₂ represents hydrogen or a linear or branched alkyl group having 1 to 20 carbon atoms, n is a number from 0 to 50, and A is a linear or branched chain having 1 to 6 carbon atoms. Of the divalent saturated hydrocarbon group. ]

The carbon number and specific examples of the alkyl group represented by R ₂ in the general formula (4A) are the same as R ₂ in the general formula (4).

  N in the general formula (4A) represents the number of added moles of alkylene oxide. The specific number of n is the same as n in the general formula (4).

  The carbon number and specific examples of A in the general formula (4A) are the same as A in the general formula (4).

  Specific examples of the compound represented by the general formula (4A) include butyl glycidyl ether, 2-ethylhexyl glycidyl ether, dodecyl glycidyl ether, (iso) stearyl glycidyl ether, and polyoxyalkylene alkyl ether-added glycidyl ether.

  The amount of the compound represented by the general formula (3A) and the compound represented by the general formula (4A) is the substituent represented by the general formula (3) and / or the general formula (4) in the obtained modified cellulose fiber. However, from the viewpoint of reactivity, it is preferably 0.01 equivalents or more, more preferably 0.1 equivalents, relative to the anhydroglucose unit of the cellulose-based raw material. Equivalent or more, more preferably 0.3 equivalent or more, still more preferably 0.5 equivalent or more, still more preferably 1.0 equivalent or more, and from the viewpoint of production cost, preferably 10 equivalent or less, More preferably, it is 8 equivalents or less, More preferably, it is 6.5 equivalents or less, More preferably, it is 5 equivalents or less.

(Ether reaction)
The ether reaction between the compound represented by the general formula (3A) or the compound represented by the general formula (4A) and the modified cellulose fiber obtained in the first aspect is the same as in the first aspect. It can be carried out by mixing both in the presence. The first embodiment can be referred to for various conditions such as the type of solvent used, the amount used, mixing conditions, and reaction temperature.

  After the reaction, an appropriate post-treatment can be performed to remove unreacted compounds, bases and the like. As the post-treatment method, for example, an unreacted base can be neutralized with an acid (organic acid, inorganic acid, etc.), and then washed with a solvent in which the unreacted compound or base dissolves. If desired, further drying (such as vacuum drying) may be performed.

  Thus, one or more substituents selected from the substituent represented by the general formula (1) and the substituent represented by the general formula (2), and the substituent represented by the general formula (3) And the modified cellulose fiber in which the 1 type (s) or 2 or more types of substituent chosen from the substituent represented by General formula (4) was introduce | transduced is obtained.

[Modified cellulose fiber]
The modified cellulose fiber in the method of the second aspect includes one or more substituents selected from the substituent represented by the general formula (1) and the substituent represented by the general formula (2), and One or more substituents selected from the substituent represented by the general formula (3) and the substituent represented by the general formula (4) are bonded to the cellulose fiber via an ether bond, and cellulose I A specific structure can be represented by, for example, the general formula (6).

[In the formula, R is the same or different and is represented by hydrogen, a substituent selected from the substituent represented by the general formula (1) and the substituent represented by the general formula (2), or the general formula (3). And m is preferably an integer of 20 or more and 3000 or less, provided that when all Rs are hydrogen at the same time, When the substituent is selected from the substituent represented by the general formula (1) and the substituent represented by the general formula (2), and the substituent represented by the general formula (3) and the general formula ( The case where it is a substituent selected from the substituent represented by 4) is excluded. ]

  M in the general formula (6) is preferably an integer of 20 or more and 3000 or less, and more preferably an integer of 100 or more and 2000 or less from the viewpoint of availability and cost.

  In the second aspect, the average fiber diameter of the cellulose fiber, the degree of crystallinity, the introduction rate of the substituent selected from the substituent represented by the general formula (1) and the substituent represented by the general formula (2) Such a range is the same as in the first embodiment, and can be determined by the same measurement method.

(Introduction rate)
Moreover, the introduction rate of the substituent selected from the substituent represented by the general formula (3) and the substituent represented by the general formula (4) with respect to 1 mol of anhydroglucose unit of the modified cellulose fiber in this embodiment is: From the viewpoint of mechanical strength and toughness expression, it has a cellulose I type crystal structure, and is preferably 1.5 mol or less, more preferably 1.0 mol or less, still more preferably 0.8 mol or less, preferably 0 0.01 mol or more, more preferably 0.02 mol or more, still more preferably 0.04 mol or more. Here, when both the substituent represented by the general formula (3) and the substituent represented by the general formula (4) are introduced, the total molar ratio of introduction.

(Miniaturization processing)
The production method of the second aspect may include a step of refining the modified cellulose fiber having the substituent introduced therein as described above. The miniaturization process can employ the processing method described in the manufacturing method of the first aspect described above.

  Thus, finely modified cellulose fibers produced by the method of this embodiment are obtained.

  The average fiber diameter of the finely modified cellulose fiber in this embodiment is preferably nano-order regardless of the type of substituent.

  The finely modified cellulose fiber is preferably 1 nm or more, more preferably 3 nm or more, further preferably 10 nm or more, and further preferably 20 nm or more from the viewpoints of handleability, availability, and cost, and exhibits mechanical strength and toughness. From this viewpoint, it is preferably 500 nm or less, more preferably 300 nm or less, still more preferably 200 nm or less, still more preferably 150 nm or less, and still more preferably 120 nm or less.

[Resin composition]
The modified cellulose fiber produced by the method of the present invention is excellent in affinity with a low-polarity medium regardless of whether or not the refinement treatment is performed. can do. Accordingly, the present invention also provides a resin composition comprising a thermoplastic resin or a curable resin and such modified cellulose fibers. The obtained resin composition can be processed according to the characteristics of the resin to be mixed.

  Hereinafter, the types of resin in the resin composition are roughly divided into two, and are described as Aspect A and Aspect B, respectively.

(Aspect A)
As the resin in the resin composition of aspect A, a thermoplastic resin or a curable resin can be used.

  As thermoplastic resins, saturated polyester resins such as polylactic acid resins; olefin resins such as polyethylene resins, polypropylene resins, and ABS resins; cellulose resins such as triacetylated cellulose and diacetylated cellulose; nylon resins; Vinyl resin; styrene resin; vinyl ether resin; polyvinyl alcohol resin; polyamide resin; polycarbonate resin; As the curable resin, a photocurable resin and / or a thermosetting resin is preferable. Specifically, epoxy resin; (meth) acrylic resin; phenol resin; unsaturated polyester resin; polyurethane resin; These resins may be used alone or as a mixed resin of two or more. In addition, in this specification, (meth) acrylic resin means what contains methacrylic resin and acrylic resin.

  Depending on the type of resin, photocuring and / or thermosetting can be performed.

  In the photocuring treatment, a polymerization reaction proceeds by using a photopolymerization initiator that generates radicals and cations by irradiation with active energy rays such as ultraviolet rays and electron beams.

  Examples of the photopolymerization initiator include acetophenones, benzophenones, ketals, anthraquinones, thioxanthones, azo compounds, peroxides, 2,3-dialkylcion compounds, disulfide compounds, thiuram compounds, fluoroamines. Compounds and the like. More specifically, 1-hydroxy-cyclohexyl-phenyl-ketone, 2-methyl-1 [4- (methylthio) phenyl] -2-morpholinopropan-1-one, benzylmethylketone, 1- (4-dodecyl) Phenyl) -2-hydroxy-2-methylpropan-1-one, 1- (4-isopropylphenyl) -2-hydroxy-2-hydroxy-2-methylpropan-1-one, benzophenone, and the like.

  With a photopolymerization initiator, for example, a monomer (monofunctional monomer or polyfunctional monomer), an oligomer having a reactive unsaturated group, a resin, or the like can be polymerized.

  When using an epoxy resin for the resin component, it is preferable to use a curing agent. By blending the curing agent, the molding material obtained from the resin composition can be firmly molded, and the mechanical strength can be improved. In addition, what is necessary is just to set content of a hardening | curing agent suitably with the kind of hardening | curing agent to be used.

  The resin in the embodiment A is one selected from the group consisting of a thermoplastic resin and a curable resin selected from an epoxy resin, a (meth) acrylic resin, a phenol resin, an unsaturated polyester resin, a polyurethane resin, or a polyimide resin. Alternatively, it is preferable to use two or more kinds of resins.

  The content of each component in the resin composition of aspect A is as follows, although it depends on the type of resin.

  The content of the resin in the resin composition of aspect A is preferably 50% by mass or more, more preferably 60% by mass or more, still more preferably 70% by mass or more, and further preferably 80% by mass, from the viewpoint of producing a molded body. % Or more, more preferably 85% by mass or more, and preferably 99.5% by mass or less, more preferably 99% by mass or less, still more preferably 98% by mass or less, more preferably from the viewpoint of containing the modified cellulose fiber. Is 95 mass% or less.

  The content of the modified cellulose fiber in the resin composition of aspect A is preferably 0.5% by mass or more, more preferably 1% by mass or more, from the viewpoint of the mechanical strength and toughness expression of the obtained resin composition. More preferably, it is 2% by mass or more, more preferably 5% by mass or more. From the viewpoint of moldability and cost of the resulting resin composition, it is preferably 50% by mass or less, more preferably 40% by mass or less, further preferably. It is 30 mass% or less, More preferably, it is 20 mass% or less, More preferably, it is 15 mass% or less.

  The amount of the modified cellulose fiber in the resin composition of aspect A is preferably 0.5 parts by mass or more, more preferably from the viewpoint of the mechanical strength and toughness expression of the resin composition obtained with respect to 100 parts by mass of the resin. Is 1 part by mass or more, more preferably 2 parts by mass or more, still more preferably 5 parts by mass or more, and from the viewpoint of moldability and cost of the resulting resin composition, preferably 100 parts by mass or less, more preferably Is 70 parts by mass or less, more preferably 45 parts by mass or less, still more preferably 25 parts by mass or less, and still more preferably 20 parts by mass or less.

  The resin composition of the embodiment A includes a compatibilizer; a plasticizer; a crystal nucleating agent; a filler (inorganic filler, organic filler); a hydrolysis inhibitor; a flame retardant; Lubricants such as hydrocarbon waxes and anionic surfactants; UV absorbers; antistatic agents; antifogging agents; light stabilizers; pigments; antifungal agents; Polysaccharides such as alginic acid; natural proteins such as gelatin, glue, casein; inorganic compounds such as tannin, zeolite, ceramics, metal powder; fragrances; flow regulators; leveling agents; conductive agents; An agent etc. can be contained in the range which does not impair the effect of this invention. Examples of the compatibilizer include a compound composed of a polar group having a high affinity for cellulose and a hydrophobic group having a high affinity for the resin. More specifically, examples of the polar group include maleic anhydride, maleic acid, and glycidyl methacrylate, and examples of the hydrophobic group include polypropylene and polyethylene. Similarly, other polymer materials and other resin compositions can be added within a range that does not impair the effects of the present invention. As a content ratio of an arbitrary additive, it may be appropriately contained as long as the effects of the present invention are not impaired. For example, in the resin composition, preferably 20% by mass or less, more preferably about 10% by mass or less. More preferably, it is about 5% by mass or less.

  The resin composition of Aspect A can be prepared without any particular limitation as long as it contains the resin and modified cellulose fibers. For example, the resin and modified cellulose fibers described above, and further contain various additives as necessary. The raw material to be prepared can be stirred by a Henschel mixer or the like, or can be prepared by a melt kneading or solvent casting method using a known kneader such as a closed kneader, a single or twin screw extruder, and an open roll kneader. .

The method for producing the resin composition of aspect A is not particularly limited as long as it includes a step of mixing the resin and finely modified cellulose fibers, or a step of simultaneously finely mixing the resin and modified cellulose fibers. Absent.
For example, the modified cellulose fiber obtained by the above-described production method, a thermoplastic resin, and a curable resin selected from an epoxy resin, a (meth) acrylic resin, a phenol resin, an unsaturated polyester resin, a polyurethane resin, or a polyimide resin The process of mixing with 1 type, or 2 or more types of resin chosen from the group which consists of is mentioned.
In this step, the modified cellulose fiber and the resin are mixed. For example, a raw material containing the resin, the modified cellulose fiber, and various additives as required can be prepared by a melt kneading or solvent casting method using a known kneader. The conditions (temperature, time) for melt kneading and solution mixing can be appropriately set according to known techniques depending on the type of resin used.

  Since the resin composition of aspect A thus obtained is excellent in mechanical strength and toughness, it can be suitably used for various applications such as household goods, household appliance parts, packaging materials for household appliance parts, and automobile parts.

(Aspect B)
In the present invention, a rubber-based resin can be used as the resin composition of aspect B. In order to increase the strength of rubber-based resin, a carbon black compounded product is widely used as a reinforcing material, but it is considered that the reinforcing effect is limited. However, in the present invention, it is considered that a resin composition excellent in mechanical strength and toughness can be provided by blending the finely modified cellulose fiber of the present invention with a rubber-based resin.

  The rubber used in the present invention is not particularly limited, but diene rubber is preferable from the viewpoint of reinforcement. In addition to diene rubbers, non-diene rubbers such as urethane rubber, silicone rubber, and polysulfide rubber can be used. Diene rubbers include natural rubber (NR), polyisoprene rubber (IR), polybutadiene rubber (BR), styrene-butadiene copolymer rubber (SBR), butyl rubber (IIR), butadiene-acrylonitrile copolymer rubber (NBR). ), Chloroprene rubber (CR) and modified rubber. Examples of the modified rubber include epoxidized natural rubber, hydrogenated natural rubber, hydrogenated butadiene-acrylonitrile copolymer rubber (HNBR), and the like. Among these, natural rubber (NR), polyisoprene rubber (IR), polybutadiene rubber (BR), styrene-butadiene copolymer rubber (from the viewpoint of achieving both good processability and high impact resilience of the rubber composition ( 1 type or 2 types or more selected from SBR), chloroprene rubber (CR) and modified rubber are preferable, and selected from natural rubber (NR), styrene-butadiene copolymer rubber (SBR), chloroprene rubber (CR) and modified rubber. One type or two or more types are more preferable. The diene rubbers can be used alone or in combination of two or more.

  When the resin composition of aspect B is a rubber composition, the content of each component is as follows.

  The rubber content in the rubber composition of aspect B is preferably 30% by mass or more, more preferably 45% by mass or more, and still more preferably 55% by mass or more, from the viewpoint of moldability of the composition. From the viewpoint of containing the modified cellulose fiber and the like, it is preferably 95% by mass or less, more preferably 90% by mass or less, still more preferably 80% by mass or less, and still more preferably 70% by mass or less.

  The content of the modified cellulose fiber in the rubber composition of the embodiment B is preferably 1% by mass or more, more preferably 2% by mass or more, and further preferably 5% by mass from the viewpoint of mechanical strength and toughness of the resulting composition. % Or more, more preferably 10% by mass or more, and from the viewpoint of operability during production, it is preferably 30% by mass or less, more preferably 20% by mass or less, and further 15% by mass or less.

  The amount of the modified cellulose fiber in the rubber composition of aspect B is preferably 1 part by mass or more, more preferably 5 parts by mass or more, and still more preferably from the viewpoint of mechanical strength and toughness obtained with respect to 100 parts by mass of rubber. Is 10 parts by mass or more, more preferably 15 parts by mass or more, and from the viewpoint of operability during production, it is preferably 30 parts by mass or less, more preferably 25 parts by mass or less, still more preferably 20 parts by mass or less. It is.

  In the rubber composition of aspect B, a reinforcing filler, a vulcanizing agent, a vulcanization accelerator, a vulcanization retarder, an aging agent which are usually used in the rubber industry, if desired, as long as the object of the present invention is not impaired. Various conventional additives for tires such as inhibitor, process oil, vegetable oil and fat, scorch inhibitor, zinc white, stearic acid, magnesium oxide, wax, phenolic resin, etc. Can be blended.

  As the reinforcing filler, carbon black, silica or the like is preferably used. As the carbon black, for example, channel black; SAF, ISAF, N-339, HAF, N-351, MAF, FEF, SRF, GPF, ECF Furnace black such as N-234; Thermal black such as FT and MT; Acetylene black and the like. Carbon black may be composed of a single species or a plurality of species.

  Examples of the vulcanizing agent include sulfur, sulfur compounds, oximes, nitroso compounds, polyamines, organic peroxides, and the like. Only one kind of vulcanizing agent may be used, or a plurality of kinds may be used in combination.

  Examples of the vulcanization accelerator include guanidine, aldehyde-amine, aldehyde-ammonia, thiazole, sulfenamide, thiourea, thiuram, dithiocarbamate, xanthate, and the like. Only one kind of vulcanization accelerator may be used, or a plurality of kinds may be used in combination.

  Examples of the vulcanization retarder include aromatic organic acids such as salicylic acid, phthalic anhydride, benzoic acid, N-nitrosodiphenylamine, N-nitroso-2,2,4-trimethyl-1,2-dihydroquinone, N- And nitroso compounds such as nitrosophenyl-β-naphthylamine. Only one kind of vulcanization retarder may be used, or a plurality of kinds may be used in combination.

  Examples of the anti-aging agent include amine-based, quinoline-based, hydroquinone derivatives, monophenol-based, polyphenol-based, thiobisphenol-based, hindered phenol-based, and phosphite-based compounds. Only one kind of anti-aging agent may be used, or a plurality of kinds may be used in combination.

  Examples of the process oil include paraffinic process oil, naphthenic process oil, and aromatic process oil. Only one kind of process oil may be used, or a plurality of kinds may be used in combination.

  Examples of vegetable oils include castor oil, cottonseed oil, linseed oil, rapeseed oil, soybean oil, palm oil, palm oil, fallen raw oil, wax, rosin, and pine oil. Only one kind of vegetable oil may be used, or a plurality of kinds may be used in combination.

  The rubber composition of aspect B can be prepared without particular limitation as long as it contains rubber and the modified cellulose fiber. For example, it can be prepared by mixing raw materials containing rubber and modified cellulose fiber and further various additives as necessary using, for example, an open kneader such as a roll or a closed kneader such as a Banbury mixer. it can. The temperature at the time of melt mixing is usually 10 to 200 ° C, preferably 20 to 180 ° C. Moreover, you may prepare by removing an organic-solvent component after preparing the solution which rubber | gum and the modified cellulose fiber melt | dissolved using the organic solvent.

The method for producing the rubber composition of aspect B is particularly suitable if it includes a step of mixing the rubber and the finely modified cellulose fiber of the present invention, or a step of refining the resin and the modified cellulose fiber simultaneously with mixing. There is no limitation.
The object to be mixed may be only rubber and modified cellulose fiber, but various additives can be used if necessary. The number of times of mixing may be one at a time, but it can also be mixed in several times, and raw materials can be added at each mixing step. For example, a step of mixing raw materials other than the vulcanizing agent (kneading step A) and a step of mixing the vulcanizing agent into the obtained mixture (kneading step B) may be performed. In addition, between the kneading step A and the kneading step B, for the purpose of lowering the viscosity of the mixture obtained in the kneading step A and for the purpose of improving the dispersibility of various additives, kneading is carried out without mixing the vulcanizing agent. The kneading step C may be performed in the same manner as in the step A. Mixing can be performed by a known method using, for example, an open kneader such as a roll or a closed kneader such as a Banbury mixer. Alternatively, the rubber composition can be obtained by dissolving the rubber using an organic solvent such as toluene, mixing the obtained rubber solution and the modified cellulose fiber, and then removing the organic solvent component by a drying process. .

  The rubber composition of Aspect B can be applied to various rubber product uses after performing an appropriate molding process as necessary using the rubber composition prepared by the above method and then vulcanizing or crosslinking. .

  Since the rubber composition of Aspect B is excellent in good mechanical strength and toughness, it can be suitably used for various uses such as household goods, household electrical appliance parts, automobile parts, among others, automobile applications.

  Moreover, as a rubber product using the rubber composition of aspect B, for example, an industrial rubber part will be described. Examples of industrial rubber parts include belts and hoses, which are extruded from the rubber composition of the present invention, which contains various additives as necessary, in accordance with the shape of each member in the unvulcanized stage. Then, after forming an unvulcanized rubber part, various industrial rubber parts can be produced by heating and pressing in a vulcanizer. Improvement of mechanical strength can improve basic performance, downsizing and thinning of parts, and improvement of durability from toughness.

  In addition, as a rubber product using the rubber composition of the aspect B, for example, when manufacturing a tire, the rubber composition of the present invention in which various additives are blended as necessary may be used as a tread at an unvulcanized stage. Extrusion processing according to the shape of each member of the tire, molding by a normal method on a tire molding machine, bonding together with other tire members, forming an unvulcanized tire, then heating in a vulcanizer A tire can be manufactured by applying pressure. From the improvement of mechanical strength, it is possible to reduce the size and thickness of each member, and from the toughness, the improvement of durability can be realized.

  Hereinafter, the present invention will be specifically described with reference to Production Examples, Preparation Examples, Examples, Comparative Examples, and Reference Examples. In addition, these Examples etc. are only illustrations of this invention, and do not mean limitation at all. The parts in the examples are parts by mass unless otherwise specified. “Normal pressure” indicates 101.3 kPa, and “room temperature” indicates 25 ° C.

Production Example 1 of Compound for Introducing Substituent <Production of Stearyl Glycidyl Ether>
A 100 liter reactor is charged with 10 kg of stearyl alcohol (Kao Co., Calcoal 8098), tetrabutylammonium bromide (Guangei Chemical Co., Ltd.) 0.36 kg, epichlorohydrin (Dow Chemical Co., Ltd.) 7.5 kg, hexane 10 kg, and nitrogen. Mixed under atmosphere. While maintaining the mixed solution at 50 ° C., 12 kg of 48 mass% sodium hydroxide aqueous solution (manufactured by Nankai Chemical Co., Ltd.) was added dropwise over 30 minutes. After completion of the dropwise addition, the mixture was further aged at 50 ° C. for 4 hours, and then repeatedly washed with 13 kg of water 8 times to remove salts and alkalis. Thereafter, the temperature in the tank was raised to 90 ° C., and hexane was distilled off from the upper layer. Under reduced pressure (6.6 kPa), steam was further blown to remove low-boiling compounds. After dehydration, 8.6 kg of white stearyl glycidyl ether was obtained by distillation under reduced pressure at an internal temperature of 250 ° C. and an internal pressure of 1.3 kPa.

Preparation Example 1 of Modified Cellulose Fiber <Addition of Phenyl Glycidyl Ether>
Softwood bleached kraft pulp (indicated as “NBKP”; average fiber diameter of 24 μm) was used as the cellulosic material.
First, 5.0 g of completely dried NBKP, 3.0 g of N, N-dimethyl-4-aminopyridine (manufactured by Wako Pure Chemical Industries, DMAP, 0.8 equivalent / AGU) and 20.0 g of acetonitrile (Wako Pure Chemical Industries, Ltd.) Product) was added and mixed uniformly, and then 13.9 g of phenylglycidyl ether (manufactured by Tokyo Chemical Industry Co., Ltd., 3.0 equivalents / AGU) was added and sealed, followed by standing reaction at 70 ° C. for 24 hours. . After the reaction, impurities are removed by washing thoroughly with toluene (Wako Pure Chemical Industries) and acetone (Wako Pure Chemical Industries), and further having an aromatic substituent by vacuum drying at 70 ° C. overnight. Modified cellulose fiber (1) was obtained.

Preparation Examples 2-5 of Modified Cellulose Fiber
Modified cellulose fibers (2) to (5) were obtained in the same manner as in Preparation Example 1 except that the aromatic ring-containing compound or the etherifying agent and the charged amount were changed as shown in Table 1.

Preparation Example 6 of Modified Cellulose Fiber <Addition of Phenyl Glycidyl Ether>
As a cellulose-based material, 5.0 g of microfibrillated cellulose (represented as “MFC”) previously substituted with acetonitrile (as solid content) (manufactured by Daicel Finechem, “Serisch FD100-G”, solid content concentration 10) Mass%, average fiber diameter of 100 nm or less, cellulose content 90 mass%, water content 3 mass%), and the same procedure as in Preparation Example 2 for modified cellulose fibers, except that no additional solvent was added. Was used to obtain a modified cellulose fiber (6) having an aromatic substituent.

Modified Cellulose Fiber Preparation Example 7 <Aromatic Dual Graft>
Stearyl obtained in Production Example 1 as an etherifying agent after adding 5.0 g of DMAP (1.1 equivalents / AGU) and 50.0 g of acetonitrile to 5.0 g of the modified cellulose fiber (1) 11.7 g (1.2 equivalents / AGU) of glycidyl ether was added and sealed, and then allowed to stand at 70 ° C. for 24 hours. After the reaction, impurities are removed by washing thoroughly with toluene and acetone, and further vacuum drying at 70 ° C. overnight to obtain a modified cellulose fiber (7) having an aromatic substituent and an aliphatic substituent. It was.

Preparation Example 8 of Modified Cellulose Fiber <Non-Aromatic Dual Graft>
A modified cellulose fiber (8) was obtained in the same manner as in Preparation Example 7, except that the modified cellulose fiber (1) was changed to the modified cellulose fiber (5).

Example 1 <Refining treatment and compounding with acrylic resin>
0.25 g of the modified cellulose fiber (1) was put into 49.75 g of DMF (manufactured by Wako Pure Chemical Industries, Ltd.), stirred at 3000 rpm for 30 minutes with a homogenizer (manufactured by Primics, TK Robotics), and then high pressure A finely modified cellulose dispersion (solid content concentration 0. 0) obtained by dispersing refined modified cellulose fibers in DMF by 10 passes at 100 MPa with a homogenizer (manufactured by Yoshida Kikai Co., Ltd., “Nanovita L-ES”). 5% by mass) was prepared. The average fiber diameter of the refined modified cellulose fiber was 24 nm.

20 g of the obtained dispersion and 2.0 g of UV-3310B (manufactured by Nippon Synthetic Chemical), which is a urethane acrylate resin, are mixed and mixed by using a high-pressure homogenizer for one pass at 60 MPa and one pass at 100 MPa. did. As a photopolymerization initiator, 0.08 g of 1-hydroxy-cyclohexyl-phenyl-ketone (manufactured by Wako Pure Chemical Industries, Ltd.) was added, and the mixture was stirred for 7 minutes using a revolving revolving stirrer Awatori Netaro (Sinky Corporation). Got. The obtained varnish was applied with a coating thickness of 2 mm using a bar coater. The solvent was removed by drying at 80 ° C. for 120 minutes. Using a UV irradiation device (Flight Systems Japan, Light Hammer 10), it is irradiated with 200 mJ / cm ² and photocured to contain 5 parts by mass of modified cellulose fiber (100 parts by mass of acrylic resin), and a thickness of about 0.1 mm. A sheet-like composite material molded body was produced.

Examples 2 to 4 and Comparative Examples 1 and 2 <Refining treatment and compounding with acrylic resin>
By replacing the modified cellulose fiber used with the modified cellulose fiber (1), except for changing to the modified cellulose fibers (2) to (6), respectively, by performing the same treatment as in Example 1, A sheet-shaped composite material molded body having a thickness of about 0.1 mm was manufactured.

Reference Example 1 <Acrylic resin blank>
Except that the modified cellulose fiber dispersion was replaced with 10 mL of DMF and the coating thickness was changed to 0.5 mm, a sheet-like acrylic resin molding having a thickness of about 0.1 mm was performed by performing the same treatment as in Example 1. The body was manufactured.

Example 5 <Compounding with rubber>
The modified cellulose fiber (7) 0.50 g was put into 49.50 g of toluene, stirred at 3000 rpm for 30 minutes with a homogenizer (Primics Co., Ltd., TK Robotics), and then a high-pressure homogenizer (Yoshida Kikai Co., Ltd., A modified cellulose dispersion (solid content concentration: 1.0% by mass) in which refined modified cellulose fibers were dispersed in toluene was obtained by performing 10 passes at 100 MPa with “NanoVita L-ES”). The average fiber diameter of the refined modified cellulose fiber was 15 nm. 10 g of the dispersion, 2.0 g of a styrene-butadiene copolymer (SBR), 0.04 g of stearic acid, 0.06 g of zinc oxide, 0.03 g of sulfur, (N- (tert-butyl) -2-benzothiazoli Add 0.01 g of rusulfenamine (TBBS), 0.01 g of di-2-benzothiazolyl disulfide (MBTS), 0.01 g of 1,3-diphenylguanidine (DPG) and 30 g of toluene at room temperature (25 ° C.). After stirring for 2 hours, the solution obtained was finely processed using a high-pressure homogenizer for 1 pass at 60 MPa and 1 pass at 100 MPa. Toluene was removed at room temperature and pressure for 2 days, then dried in a vacuum dryer (room temperature) for 12 hours and vulcanized at 150 ° C for 1 hour. In, it was prepared vulcanized rubber sheet having a thickness of about 0.2 mm.

Comparative Example 3 <Compounding with rubber>
5 parts by mass of the modified cellulose fiber is obtained by performing the same treatment as in Example 5 except that the modified cellulose fiber is changed to the modified cellulose fiber (8) instead of the modified cellulose fiber (7). A vulcanized rubber sheet having a thickness of about 0.2 mm containing (100 parts by mass of SBR) was prepared.

Reference Example 2 <SBR blank>
A vulcanized rubber sheet having a thickness of about 0.2 mm was produced by carrying out the same treatment as in Example 5 except that the modified cellulose fiber was not used.

  About the obtained modified cellulose fiber, the substituent introduction rate, the average fiber diameter (including the average fiber diameter of the cellulose-based raw material), and the confirmation (crystallinity) of the crystal structure are evaluated according to the methods of Test Examples 1 to 3. did. Further, the mechanical properties of the molded bodies were evaluated according to the method of Test Example 4. The average fiber diameter of the refined modified cellulose fibers was evaluated according to the method of Test Example 5. The results are shown in Tables 2-3.

Test Example 1 (Substituent introduction rate (substitution degree))
The content% (mass%) of the hydrophobic ether group contained in the obtained modified cellulose fiber was measured by Analytical Chemistry, Vol. 51, no. 13, 2172 (1979), Zeisel method known as a technique for analyzing the average number of moles of an alkoxy group added to cellulose ether, as described in “Fifteenth revised Japanese pharmacopoeia (hydroxypropylcellulose analysis method)”, etc. It calculated according to. The procedure is shown below.

(I) 0.1 g of n-octadecane was added to a 200 mL volumetric flask, and the volume was increased to the marked line with hexane to prepare an internal standard solution.
(Ii) Refined and dried modified cellulose fiber 100 mg and adipic acid 100 mg were precisely weighed into a 10 mL vial, and 2 mL of hydroiodic acid was added and sealed.
(Iii) The mixture in the vial was heated with a block heater at 160 ° C. for 1 hour while stirring with a stirrer chip.
(Iv) After heating, 3 mL of the internal standard solution and 3 mL of diethyl ether were sequentially injected into the vial and stirred at room temperature for 1 minute.
(V) The upper layer (diethyl ether layer) of the mixture separated into the two phases in the vial was analyzed by gas chromatography (manufactured by SHIMADZU, “GC2010Plus”) to quantify the etherifying agent. The analysis conditions were as follows.
Column: DB-5 manufactured by Agilent Technologies (12 m, 0.2 mm × 0.33 μm)
Column temperature: 100 ° C. → 10 ° C./min→280° C. (10 min Hold)
Injector temperature: 300 ° C., detector temperature: 300 ° C., implantation amount: 1 μL
The ether group content (% by mass) in the modified cellulose fiber was calculated from the detected amount of the etherifying agent used, that is, the aromatic ring-containing alkylene oxide compound.

From the obtained ether group content, the degree of molar substitution (MS) (substituent molar amount relative to 1 mol of anhydroglucose unit) was calculated using the following mathematical formula (1).
(Formula 1)
MS = (W1 / Mw) / ((100−W1) /162.14)
W1: Ether group content (% by mass) in the modified cellulose fiber
Mw: Molecular weight of the introduced etherifying agent (g / mol)

Test Example 2 (Average fiber diameter of modified cellulose fiber and cellulose-based raw material)
The fiber diameters of the modified cellulose fiber and the cellulose-based raw material were determined by the following method.
About 0.3 g of the absolutely dried sample was precisely weighed and stirred for 1 minute in 1.0 L of ion-exchanged water using a home-use mixer to break the fibers into water. Thereafter, 4.0 L of ion-exchanged water was further added and stirred to be uniform. From the obtained aqueous dispersion, about 50 g was collected as a measurement liquid and precisely weighed. The obtained measurement liquid was analyzed by “Kajaani Fiber Lab” manufactured by Metso Automation Co., to obtain an average fiber diameter.

Test Example 3 (Confirmation of crystal structure)
The crystal structure of the modified cellulose fiber was confirmed by measuring under the following conditions using “RigakuRINT 2500VC X-RAY diffractometer” manufactured by Rigaku Corporation.
The measurement conditions were X-ray source: Cu / Kα-radiation, tube voltage: 40 kv, tube current: 120 mA, measurement range: diffraction angle 2θ = 5-45 °, and X-ray scan speed: 10 ° / min. The measurement sample was prepared by compressing a pellet having an area of 320 mm ² × thickness of 1 mm. Further, the crystallinity of the cellulose type I crystal structure was calculated based on the following formula (A) using the obtained X-ray diffraction intensity.
Cellulose type I crystallinity (%) = [(I22.6-I18.5) /I22.6] × 100 (A)
[Wherein I22.6 is the diffraction intensity of the grating plane (002 plane) (diffraction angle 2θ = 22.6 °) in X-ray diffraction, and I18.5 is the amorphous portion (diffraction angle 2θ = 18.5 °). (Indicates diffraction intensity)

Test example 4 (tensile modulus)
In a thermostatic chamber at 25 ° C., the tensile modulus of the molded product was measured by a tensile test in accordance with JIS K7113 using a tensile / compression tester (manufactured by SHIMADZU, “Autograph AGS-X”). Three samples were prepared by punching any three parts of the molded body with No. 2 dumbbell. Each sample was set at a fulcrum distance of 40 mm and measured at a crosshead speed of 20 mm / min. The average elastic modulus of the three samples at 0.5-1.5% elongation at break is the “initial modulus”, (average elasticity of the three samples at 89.5-90.5% elongation at break) Ratio) / (average elastic modulus of three samples at 0.5-1.5% elongation at break) was defined as "elastic retention". The higher the initial elastic modulus, the better the mechanical strength at low strain, the higher the elastic modulus, the better the mechanical strength at low strain to the high strain region, that is, excellent toughness. It shows that.

Test Example 5 (Average fiber diameter of finely modified cellulose fiber)
A solvent is further added to the dispersions obtained in each of Examples and Comparative Examples to prepare a 0.0001 mass% dispersion, and the dispersion is dropped onto mica (mica) and dried as an observation sample. Using an atomic force microscope (AFM, Nanoscope III Tapping mode AFM, manufactured by Digital instrument, and probe using Nano Probes Point Probe (NCH)), the fiber height of the cellulose fiber in the observed sample was measured. It was measured. At that time, five or more cellulose fibers were extracted from the microscopic image in which the cellulose fibers can be confirmed, and the average fiber diameter (fiber diameter in the dispersion) was calculated from the fiber height.

  From Tables 2-3, it can be seen that by combining the modified cellulose fiber obtained by the production method of the present invention with a resin, high mechanical strength and toughness can be expressed in a wide range of applications regardless of the type of resin. . In particular, Comparative Example 2 corresponds to the technique of Patent Document 1 described in the Background Art section, and is obtained by refining cellulose fibers and then etherifying them to obtain modified cellulose fibers. When compared with Example 1 using the same etherifying agent as Comparative Example 2, it can be seen that the Example is significantly superior in mechanical strength and toughness.

  Since the molded product obtained by combining the modified cellulose fiber obtained by the production method of the present invention with a resin has both high mechanical strength and toughness, it is a daily miscellaneous goods, household appliance parts, packaging materials for household appliance parts, It can be suitably used for various industrial applications such as automobile parts.

Claims (6)

After introducing one or two or more compounds selected from an aromatic ring-containing alkylene oxide compound and an aromatic ring-containing glycidyl ether compound through an ether bond in the presence of a base with respect to a cellulose-based raw material, a refinement treatment is performed. A method for producing a modified cellulose fiber, comprising:
The modified cellulose fiber has one or more substituents selected from the substituent represented by the following general formula (1) and the substituent represented by the following general formula (2) via an ether bond. A method for producing a modified cellulose fiber, which is bonded to a cellulose fiber and has a cellulose I-type crystal structure.
—CH ₂ —CH (OH) —R ₁ (1)
—CH ₂ —CH (OH) —CH ₂ — (OA) _n —O—R ₁ (2)
[Wherein, R ₁ in the general formula (1) and the general formula (2) each independently represents a functional group having 6 to 30 carbon atoms having at least one aromatic ring, and n in the general formula (2) Represents a number of 0 to 50, and A represents a linear or branched divalent saturated hydrocarbon group having 1 to 6 carbon atoms. ]   A resin composition comprising the modified cellulose fiber obtained by the production method according to claim 1 and a resin. A modified cellulose fiber having an average fiber diameter of 5 μm or more, and one or more selected from a substituent represented by the following general formula (1) and a substituent represented by the following general formula (2) The modified cellulose fiber has a cellulose I-type crystal structure in which the substituents are bonded to the cellulose fiber via an ether bond.
—CH ₂ —CH (OH) —R ₁ (1)
—CH ₂ —CH (OH) —CH ₂ — (OA) _n —O—R ₁ (2)
[Wherein, R ₁ in the general formula (1) and the general formula (2) each independently represents a functional group having 6 to 30 carbon atoms having at least one aromatic ring, and n in the general formula (2) Represents a number of 0 to 50, and A represents a linear or branched divalent saturated hydrocarbon group having 1 to 6 carbon atoms. ] One or more substituents selected from the substituent represented by the following general formula (1) and the substituent represented by the following general formula (2), and the substitution represented by the following general formula (3) A modified cellulose fiber having a cellulose I-type crystal structure in which one or two or more substituents selected from a group represented by the following general formula (4) are bonded to a cellulose fiber via an ether bond .
—CH ₂ —CH (OH) —R ₁ (1)
—CH ₂ —CH (OH) —CH ₂ — (OA) _n —O—R ₁ (2)
[Wherein, R ₁ in the general formula (1) and the general formula (2) each independently represents a functional group having 6 to 30 carbon atoms having at least one aromatic ring, and n in the general formula (2) Represents a number of 0 to 50, and A represents a linear or branched divalent saturated hydrocarbon group having 1 to 6 carbon atoms. ]
—CH ₂ —CH (OH) —R ₂ (3)
—CH ₂ —CH (OH) —CH ₂ — (OA) _n —O—R ₂ (4)
[Wherein, R ₂ in general formula (3) and general formula (4) each independently represents hydrogen or a linear or branched alkyl group having 1 to 20 carbon atoms, and n in general formula (4) Represents a number of 0 to 50, and A represents a linear or branched divalent saturated hydrocarbon group having 1 to 6 carbon atoms. ] One or more compounds selected from an aromatic ring-containing alkylene oxide compound and an aromatic ring-containing glycidyl ether compound, an alkylene oxide compound represented by the general formula (3A), and a general formula A method for producing a modified cellulose fiber, wherein one or two or more compounds selected from glycidyl ether compounds represented by (4A) are introduced via an ether bond,
The modified cellulose fiber is one or more substituents selected from the substituent represented by the following general formula (1) and the substituent represented by the following general formula (2), and the following general formula ( 1 type or 2 or more types of substituents chosen from the substituent represented by 3) and the substituent represented by following General formula (4) couple | bonded with a cellulose fiber via an ether bond, and cellulose I type crystal structure The manufacturing method of the modified cellulose fiber which has this.
—CH ₂ —CH (OH) —R ₁ (1)
—CH ₂ —CH (OH) —CH ₂ — (OA) _n —O—R ₁ (2)
[Wherein, R ₁ in the general formula (1) and the general formula (2) each independently represents a functional group having 6 to 30 carbon atoms having at least one aromatic ring, and n in the general formula (2) Represents a number of 0 to 50, and A represents a linear or branched divalent saturated hydrocarbon group having 1 to 6 carbon atoms. ]
—CH ₂ —CH (OH) —R ₂ (3)
—CH ₂ —CH (OH) —CH ₂ — (OA) _n —O—R ₂ (4)

[Wherein, R ₂ in the general formulas (3), (3A), (4) and (4A) each independently represents hydrogen or a linear or branched alkyl group having 1 to 20 carbon atoms; In formulas (4) and (4A), n represents a number of 0 to 50, and A represents a linear or branched divalent saturated hydrocarbon group having 1 to 6 carbon atoms. ]   A resin composition comprising the modified cellulose fiber according to claim 4 or the modified cellulose fiber obtained by the production method according to claim 5 and a resin.