JP6779158B2 - Method for manufacturing modified cellulose fiber - Google Patents

Description

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

Conventionally, petroleum-derived plastic materials, which are a finite resource, have been widely used, but in recent years, technologies with less impact on the environment have come into the limelight, and under such technological background, biomass is naturally present in large quantities. Materials using cellulose fibers are attracting attention.

For example, Patent Document 1 discloses a specific surface substitution in which a hydroxyl functional group is etherified with an organic compound for the purpose of providing a cellulose microfibril with significantly reduced hydrophilicity while retaining advantageous mechanical properties. Cellulose microfibrils with a degree are disclosed.

Special Table 2002-524618

However, the cellulose microfibrils of Patent Document 1 are not sufficiently satisfactory in terms of mechanical strength and toughness of a molded product manufactured by compounding with a resin.

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

The present invention relates to the following [1] to [6].
[1] In the presence of a base, one or more compounds selected from an aromatic ring-containing oxide alkylene compound and an aromatic ring-containing glycidyl ether compound are introduced into a cellulosic raw material via an ether bond, and then micronized. Is a method for producing a modified cellulose fiber,
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 type I crystal structure.
-CH _2- CH (OH) -R ₁ (1)
-CH _2- CH (OH) -CH _2- (OA) _n- O-R ₁ (2)
[In the formula, R ₁ in the general formula (1) and the general formula (2) each independently represents a functional group having at least one aromatic ring and having 6 to 30 carbon atoms, and n in the general formula (2). Indicates a number of 0 or more and 50 or less, and A indicates a linear or branched divalent saturated hydrocarbon group having 1 or more and 6 or less carbon atoms. ]
[2] A resin composition containing the modified cellulose fiber obtained by the production method according to the above [1] and a resin.
[3] A modified cellulose fiber having an average fiber diameter of 5 μm or more, which is selected from a substituent represented by the following general formula (1) and a substituent represented by the following general formula (2). A modified cellulose fiber having a cellulose type I crystal structure in which two or more kinds of 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)
[In the formula, R ₁ in the general formula (1) and the general formula (2) each independently represents a functional group having at least one aromatic ring and having 6 to 30 carbon atoms, and n in the general formula (2). Indicates a number of 0 or more and 50 or less, and A indicates a linear or branched divalent saturated hydrocarbon group having 1 or more and 6 or less carbon atoms. ]
[4] One or more substituents selected from the substituents represented by the following general formula (1) and the substituents represented by the following general formula (2), and the following general formula (3). One or more substituents selected from the substituents and the substituents represented by the following general formula (4) are bonded to the cellulose fibers via an ether bond and have a cellulose type I crystal structure. Quality cellulose fiber.
-CH _2- CH (OH) -R ₁ (1)
-CH _2- CH (OH) -CH _2- (OA) _n- O-R ₁ (2)
[In the formula, R ₁ in the general formula (1) and the general formula (2) each independently represents a functional group having at least one aromatic ring and having 6 to 30 carbon atoms, and n in the general formula (2). Indicates a number of 0 or more and 50 or less, and A indicates a linear or branched divalent saturated hydrocarbon group having 1 or more and 6 or less carbon atoms. ]
-CH ₂ -CH (OH) -R ₂ (3)
-CH _2- CH (OH) -CH _2- (OA) _n- O-R ₂ (4)
[In the formula, R ₂ in the general formula (3) and the general formula (4) independently represent a hydrogen or a linear or branched alkyl group having 1 to 20 carbon atoms, and n in the general formula (4). Indicates a number of 0 or more and 50 or less, and A indicates a linear or branched divalent saturated hydrocarbon group having 1 or more and 6 or less carbon atoms. ]
[5] One or more compounds selected from an aromatic ring-containing alkylene compound and an aromatic ring-containing glycidyl ether compound in the presence of a base, and an alkylene oxide compound represented by the general formula (3A) with respect to a cellulosic raw material. A method for producing a modified cellulose fiber, wherein one or more compounds selected from the glycidyl ether compound represented by the general formula (4A) is introduced via an ether bond.
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), and the following general formula ( One or more substituents selected from the substituent represented by 3) and the substituent represented by the following general formula (4) are bonded to the cellulose fiber via an ether bond to form a cellulose type I crystal structure. A method for producing a modified cellulose fiber.
-CH _2- CH (OH) -R ₁ (1)
-CH _2- CH (OH) -CH _2- (OA) _n- O-R ₁ (2)
[In the formula, R ₁ in the general formula (1) and the general formula (2) each independently represents a functional group having at least one aromatic ring and having 6 to 30 carbon atoms, and n in the general formula (2). Indicates a number of 0 or more and 50 or less, and A indicates a linear or branched divalent saturated hydrocarbon group having 1 or more and 6 or less carbon atoms. ]
-CH ₂ -CH (OH) -R ₂ (3)
-CH _2- CH (OH) -CH _2- (OA) _n- O-R ₂ (4)

[In the formula, R ₂ in the general formulas (3), (3A), (4) and (4A) independently represent hydrogen or a linear or branched alkyl group having 1 to 20 carbon atoms, and is generally used. In the formulas (4) and (4A), n is a number of 0 or more and 50 or less, and A is a linear or branched divalent saturated hydrocarbon group having 1 or more and 6 or less carbon atoms. ]
[6] A resin composition containing the modified cellulose fiber according to the above [4] or the modified cellulose fiber obtained by the production method according to the above [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 having excellent mechanical strength and toughness in a molded product with a resin.

The molded product 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 an action and effect, it is difficult for even a person skilled in the art to predict the occurrence of such an action and effect.

[Manufacturing method of modified cellulose fiber]
Specific examples of the production method of the present invention include the following two aspects. In the first aspect, one or more compounds selected from an aromatic ring-containing oxide alkylene compound and an aromatic ring-containing glycidyl ether compound are introduced into a cellulosic raw material via an ether bond in the presence of a base, and then This is a method for producing a modified cellulose fiber, which is subjected to a micronization treatment. The second aspect is represented by the general formula (3A) with one or more compounds selected from the aromatic ring-containing oxide alkylene compound and the aromatic ring-containing glycidyl ether compound with respect to the cellulosic raw material in the presence of a base. This is a method for producing a modified cellulose fiber, in which one or more compounds selected from the alkylene oxide compound and the glycidyl ether compound represented by the general formula (4A) are introduced via an ether bond. In addition, in this specification, "bonding through an ether bond" means a state in which a modifying group reacts with a hydroxyl group on the surface of a cellulose fiber, and an ether bond is formed. 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 the first aspect]
The modified cellulose fiber produced by the method of the first aspect is one or more selected from the substituents represented by the following general formula (1) and the substituents represented by the following general formula (2). The substituent is bonded to the cellulose fiber via an ether bond and has a cellulose type I crystal structure.
-CH _2- CH (OH) -R ₁ (1)
-CH _2- CH (OH) -CH _2- (OA) _n- O-R ₁ (2)
[In the formula, R ₁ in the general formula (1) and the general formula (2) each independently represents a functional group having at least one aromatic ring and having 6 to 30 carbon atoms, and n in the general formula (2). Indicates a number of 0 or more and 50 or less, and A indicates a linear or branched divalent saturated hydrocarbon group having 1 or more and 6 or less carbon atoms. ]

(Cellulose-based raw material)
The cellulosic raw material used in the present invention is not particularly limited, and is wood-based (coniferous / broad-leaved), herbaceous (plant material of rice family, blue-green family, legume family, non-wood raw material of palm family plant), pulp. Species (cotton linter pulp obtained from fibers around cotton seeds, etc.), papers (newsprint, cardboard, magazines, woodfree paper, etc.) and the like. Of these, woody and herbaceous are preferable from the viewpoint of availability and cost.

The shape of the cellulosic raw material is not particularly limited, but is preferably fibrous, powdery, spherical, chip-shaped, or flake-shaped from the viewpoint of handleability. Moreover, it may be a mixture of these.

In addition, the cellulosic raw material can be pretreated with 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 in the drug to be used, and examples thereof include treatments using enzymes such as endoglucanase, exoglucanase, and beta-glucosidase. The chemical treatment is not particularly limited in the chemicals used, and examples thereof include acid treatment with hydrochloric acid and sulfuric acid, and oxidation treatment with hydrogen peroxide and ozone. The machine processing is not particularly limited in the machine used and the processing conditions. For example, a high-pressure compression roll mill, a roll mill such as a roll rotation mill, a ring roller mill, a roller race mill, or a vertical roller mill such as a ball race mill, Container drive medium mills such as rolling ball mills, vibrating ball mills, vibrating rod mills, vibrating tube mills, planetary ball mills or centrifugal fluidization mills, tower type crushers, stirring tank type mills, distribution tank type mills or general type mills and the like. Examples thereof include compact shear mills such as type mills, high-speed centrifugal roller mills and ong mills, grinders such as mortars, stone mills, mass colloiders, fret mills and edge runner mills, knife mills, pin mills and cutter mills.

In addition, during the above mechanical treatment, solvents such as water, ethanol, isopropyl alcohol, t-butyl alcohol, toluene and xylene, plasticizers such as phthalic acid, adipic acid and trimellitic acid, urea and alkali (earth) ) It is also possible to promote the shape change by mechanical treatment by adding an auxiliary agent such as a metal hydroxide or a hydrogen bond inhibitor such as an amine compound. By adding the shape change in this way, the handleability of the cellulosic raw material is improved, the introduction of the substituent is improved, and the physical properties of the obtained modified cellulosic fiber can be improved. The amount of the additive aid used varies depending on the additive aid used, the machine treatment method used, etc., but from the viewpoint of exhibiting the effect of promoting the shape change, it is preferably 5 parts by mass or more with respect to 100 parts by mass of the raw material. , More preferably 10 parts by mass or more, further preferably 20 parts by mass or more, and from the viewpoint of exhibiting the effect of promoting shape change and economically, preferably 10,000 parts by mass or less, more preferably 5000 parts by mass. Parts or less, more preferably 3000 parts by mass 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, still more preferably 15 μm or more, from the viewpoint of handleability and cost. Although the upper limit is not particularly set, 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, still more preferably 100 μm or less. Is.

For the average fiber diameter of the cellulosic raw material, for example, the absolutely dried cellulose fibers are stirred in ion-exchanged water using a household mixer or the like to dissolve the fibers, and then ion-exchanged water is further added and stirred so as to be uniform. A method of analyzing a part of the obtained aqueous dispersion with "Kajaani Fiber Lab" manufactured by Mezzo Automation Co., Ltd. can be mentioned. By such a method, the 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, 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, still more preferably 90% by mass or less. Here, the cellulosic content in the cellulosic raw material is the cellulosic content in the residual component excluding water in the cellulosic raw material.

Further, the water content in the cellulosic raw 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, further preferably 30% by mass or less, still more preferably 20% by mass or less, still more preferably an absolute dry treatment, that is, 10% by mass or less.

(base)
The introduction of the substituent is carried out in the presence of a base. The base used here is not particularly limited, but from the viewpoint of advancing the etherification reaction, alkali metal hydroxide, alkaline earth metal hydroxide, 1-3 amine, quaternary ammonium salt, imidazole and the like. One or more selected from the group consisting of its derivatives, pyridines and derivatives thereof, and alkoxides is preferable.

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

The 1st to 3rd amines are primary amines, secondary amines, and tertiary amines, and specific examples thereof include ethylenediamine, diethylamine, proline, N, N, N', and N'-tetramethylethylenediamine. N, N, N', N'-tetramethyl-1,3-propanediamine, N, N, N', N'-tetramethyl-1,6-hexanediamine, tris (3-dimethylaminopropyl) amine, Examples thereof include N, N-dimethylcyclohexylamine and triethylamine.

Examples of the quaternary ammonium salt include tetrabutylammonium hydroxide, tetrabutylammonium chloride, tetrabutylammonium fluoride, tetrabutylammonium bromide, tetraethylammonium hydroxide, tetraethylammonium chloride, tetraethylammonium fluoride, tetraethylammonium bromide, and water. Examples thereof include tetramethylammonium oxide, tetramethylammonium chloride, tetramethylammonium fluoride, tetramethylammonium bromide and the like.

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

Examples of pyridine and its derivatives include N, N-dimethyl-4-aminopyridine, picoline and the like.

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

The amount of the base is preferably 0.01 equivalent or more, more preferably 0.05 equivalent or more, still more preferably 0.1, from the viewpoint of advancing the etherification reaction with respect to the anhydrous glucose unit of the cellulosic raw material. Equivalent or more, more preferably 0.2 equivalent or more, and from the viewpoint of manufacturing cost, preferably 10 equivalent or less, more preferably 8 equivalent or less, still more preferably 5 equivalent or less, still more preferably 3 equivalent. It is less than the amount. The anhydrous glucose unit is abbreviated as "AGU". AGU is calculated on the assumption that all cellulosic raw materials are composed of anhydrous glucose units.

The cellulosic raw material and the base may be mixed in the presence of a solvent. The solvent is not particularly limited, and for example, water, isopropanol, t-butanol, dimethylformamide, toluene, methyl isobutyl ketone, acetonitrile, dimethyl sulfoxide, dimethylacetamide, 1,3-dimethyl-2-imidazolidinone, hexane, etc. Included are 1,4-dioxane, and mixtures thereof.

As long as the cellulosic raw material and the base can be mixed uniformly, the temperature and time are not particularly limited.

(Aromatic ring-containing alkylene compound and aromatic ring-containing glycidyl ether compound)
Next, one or more compounds selected from the aromatic ring-containing oxide alkylene compound and the aromatic ring-containing glycidyl ether compound are added to the mixture of the cellulosic raw material and the base obtained above to obtain the substituent. It binds to cellulose fibers.

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

The aromatic ring-containing glycidyl ether compound is used to bond the substituent represented by the general formula (2) to the cellulose fiber. Examples of the aromatic ring-containing glycidyl ether compound include an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, and a glycidyl ether compound having a heteroaromatic ring having 6 to 20 carbon atoms. Specific examples thereof include phenylglycidyl ether, trityl glycidyl ether, benzyl glycidyl ether and derivatives thereof. Among these, phenylglycidyl ether and tritylglycidyl ether are preferable from the viewpoint of availability and reactivity, and phenylglycidyl 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 the substituent in the obtained 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 equal or less, more preferably 8.0 or the like, relative to one unit of the anhydrous glucose unit of the cellulose-based raw material. Amount or less, more preferably 7.0 equal or less, still more preferably 6.0 equal or less, preferably 0.02 equal or more, more preferably 0.05 equal or more, still more preferably 0.1 equal or less. The above is more preferably 0.3 equal or more, still more preferably 1.0 equal or more. Here, when both the aromatic ring-containing alkylene oxide compound and the aromatic ring-containing glycidyl ether compound are used, the amount of the compound is the total amount of both.

(Ether reaction)
The ether reaction between the compound and the cellulosic raw material can be carried out by mixing both in the presence of a solvent. The solvent is not particularly limited, and the solvent exemplified as being usable when a base is present can be used.

The amount of the solvent used is not unconditionally 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. The above is more preferably 50 parts by mass or more, further preferably 75 parts by mass or more, further preferably 100 parts by mass or more, still more preferably 200 parts by mass or more, and preferably 10,000 parts by mass or less from the viewpoint of productivity. , More preferably 7,500 parts by mass or less, further preferably 5,000 parts by mass or less, still more preferably 2,500 parts by mass or less, still more preferably 1,000 parts by mass or less.

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

The reaction temperature is not unconditionally determined by the type of the compound for introducing the cellulosic raw material or the substituent and the target introduction rate, but from the viewpoint of improving the reactivity, it is preferably 30 ° C. or higher, more preferably. It is 35 ° C. or higher, more preferably 40 ° C. or higher, and 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 preferable. Is 80 ° C. or lower, more preferably 70 ° C. or lower.

The reaction time is not unconditionally determined by the type of the compound for introducing the cellulosic raw material or the substituent and the target introduction rate, but from the viewpoint of reactivity, it is preferably 0.1 hour or more, more preferably 0.1 hour or more. It is 0.5 hours or more, more preferably 1 hour or more, further preferably 3 hours or more, still more preferably 6 hours or more, still more preferably 10 hours or more, and 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, post-treatment can be appropriately performed in order to remove unreacted compounds, bases and the like. As a method of the post-treatment, for example, an unreacted base can be neutralized with an acid (organic acid, inorganic acid, etc.), and then washed with an unreacted compound or a solvent in which the base dissolves. If desired, further drying (vacuum drying or the like) may be performed.

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

[Modified cellulose fiber before miniaturization treatment]
The modified cellulose fiber before the micronization 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). The substituent is bonded to the cellulose fiber via an ether bond and has a cellulose type I crystal structure, and the specific structure can be represented by, for example, the general formula (5).

[In the formula, R is the same or different and represents a substituent selected from hydrogen and the substituents represented by the general formulas (1) and (2), and m preferably represents an integer of 20 or more and 3000 or less. , Except when all Rs are hydrogen at the same time. ]

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 substituents represented by the general formula (1) and the substituents represented by the general formula (2) in the general formula (5) are as follows. Even if the substituent represented by the general formula (1) or the substituent represented by the general formula (2) in the modified cellulose fiber is either one, the same substituent is used in each substituent. Even if it is, two or more kinds may be introduced in combination.
-CH _2- CH (OH) -R ₁ (1)
-CH _2- CH (OH) -CH _2- (OA) _n- O-R ₁ (2)
[In the formula, R ₁ in the general formula (1) and the general formula (2) each independently represents a functional group having at least one aromatic ring and having 6 to 30 carbon atoms, and n in the general formula (2). Indicates a number of 0 or more and 50 or less, and A indicates a linear or branched divalent saturated hydrocarbon group having 1 or more and 6 or less carbon atoms. ]

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

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

A in the general formula (2) is a linear or branched divalent saturated hydrocarbon group having 1 or more and 6 or less 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 is preferably 2 or more from the viewpoint of availability and cost, and preferably 4 or less, more preferably 3 or less from the same viewpoint. Specifically, a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group and the like are exemplified, and among them, an ethylene group and a propylene group are preferable, and an ethylene group is more preferable.

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

(Average fiber diameter)
The average fiber diameter of the modified cellulose fiber before the micronization treatment in the method of the first aspect is preferably 5 μm or more regardless of the type of substituent. From the viewpoint of handleability, availability, and cost, it is more preferably 7 μm or more, further preferably 10 μm or more, still more preferably 15 μm or more. Although the upper limit is not particularly set, 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, still more preferably 100 μm or less. Is. The average fiber diameter of the modified cellulose fiber can be measured in the same manner as the above-mentioned cellulosic 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, still more preferably 20% or more from the viewpoint of strength development. Further, from the viewpoint of raw material availability, it is preferably 90% or less, more preferably 85% or less, still more preferably 80% or less, still more preferably 75% or less. In the present specification, the crystallinity of cellulose is the cellulose type I crystallinity calculated from the diffraction intensity value by the X-ray diffraction method, and can be measured according to the method described in Examples described later. The cellulose type I is the crystal form of natural cellulose, and the cellulose type I crystallinity means the ratio of the amount of the crystal region to the whole cellulose. The presence or absence of the cellulose type I crystal structure can be determined by the peak at 2θ = 22.6 ° in the X-ray diffraction measurement.

(Introduction rate)
In the modified cellulose fiber before the micronization 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 the anhydrous glucose unit of cellulose. The introduction rate (MS) of the group is preferably 0.001 mol or more, more preferably 0.005 mol or more, still more preferably 0.03 mol or more, from the viewpoint of mechanical strength and toughness development. Further, it has a cellulose type I crystal structure, and from the viewpoint of mechanical strength and toughness development, 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. It is 0.8 mol or less, more preferably 0.6 mol or less, 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 is the total introduced molar ratio. In this specification, the introduction rate can be measured according to the method described in Examples described later, and may also be described as the introduction molar ratio or the modification rate.

(Miniaturization processing)
The method for producing a modified cellulose fiber of the first aspect includes a step of refining the modified cellulose fiber before the micronization treatment. The miniaturization treatment can be carried out by a known miniaturization treatment method. For example, when a finely modified cellulose fiber having an average fiber diameter of 1 nm or more and 500 nm or less is obtained, it is refined by a treatment using a grinder such as a mass colloider 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 mixed and refined at the same time. Further, the modified cellulose fiber in the present invention is subjected to the same treatment as the pretreatment for the cellulosic raw material as described above after the reaction, for example, in the form of chips or flakes. It may be in powder form. Since the shape change is brought about by such treatment, the efficiency of the miniaturization treatment can be improved when the obtained modified cellulose fiber of the present invention is miniaturized in an organic solvent or a resin composition. In the present specification, the modified cellulose fiber after the micronization treatment may be referred to as "finely modified cellulose fiber" from the viewpoint of distinguishing it from the modified cellulose fiber before the micronization treatment.

The organic solvent used for the micronization treatment for obtaining finely modified cellulose fibers having an average fiber diameter of 1 nm or more and 500 nm or less is not particularly limited, but for example, methanol, ethanol, propanol and the like have 1 to 6 carbon atoms, preferably. Alcohols with 1 to 3 carbon atoms; Ketones with 3 to 6 carbon atoms such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; Linear or branched saturated or unsaturated hydrocarbons with 1 to 6 carbon atoms; Benzene, toluene, etc. 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, dimethylsulfoxide, succinic acid and Examples thereof include polar solvents such as diesters with triethylene glycol monomethyl ether. These can be used alone or in combination of two or more, but from the viewpoint of operability of the micronization treatment, alcohol having 1 to 6 carbon atoms, ketone having 3 to 6 carbon atoms, and 2 to 5 carbon atoms can be used. Lower alkyl ethers, N, N-dimethylformamide, methyl succinate triglycol diester, toluene and the like are preferred. The amount of the solvent used may be an effective amount capable of dispersing the modified cellulose fibers and is not particularly limited, but is preferably 1% by mass or more, more preferably 2% by mass or more, preferably 2% by mass or more, based on the modified cellulose fibers. Is more preferably 500 times by mass or less, more preferably 200 times by mass or less.

Further, as an apparatus used in the miniaturization process, a known disperser is preferably used in addition to the high-pressure homogenizer. For example, a breaker, a beater, a low-pressure homogenizer, a grinder, a mascoroider, 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 miniaturization treatment is preferably 50% by mass or less.

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

Thus, the finely modified cellulose fibers produced by the method of the first aspect are obtained.

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

(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, further preferably 10 nm or more, still more preferably 20 nm or more, and handleability, from the viewpoint of handleability, availability, and cost. From the viewpoint of mechanical strength and toughness development, 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, still more preferably 120 nm or less. In this specification, the average fiber diameter of the finely modified cellulose fiber can be measured according to the following method.

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

Since the crystallinity of the modified cellulose fiber and the introduction rate of substituents are hardly affected by the micronization treatment, these properties are the same as those of the modified cellulose fiber before the miniaturization treatment.

[Method for producing modified cellulose fiber of the second aspect]
The modified cellulose fiber produced by the method of this embodiment has one or more substitutions selected from the substituents represented by the following general formula (1) and the substituents represented by the following general formula (2). One or more substituents selected from the group and the substituent represented by the following general formula (3) and the substituent represented by the following general formula (4) are bonded to the cellulose fiber via an ether bond. It has a cellulose type I crystal structure.
-CH _2- CH (OH) -R ₁ (1)
-CH _2- CH (OH) -CH _2- (OA) _n- O-R ₁ (2)
[In the formula, R ₁ in the general formula (1) and the general formula (2) each independently represents a functional group having at least one aromatic ring and having 6 to 30 carbon atoms, and n in the general formula (2). Indicates a number of 0 or more and 50 or less, and A indicates a linear or branched divalent saturated hydrocarbon group having 1 or more and 6 or less carbon atoms. ]
-CH _2- CH (OH) -R ₂ (3)
-CH _2- CH (OH) -CH _2- (OA) _n- O-R ₂ (4)
[In the formula, R ₂ in the general formula (3) and the general formula (4) independently represent a hydrogen or a linear or branched alkyl group having 1 to 20 carbon atoms, and n in the general formula (4). Indicates a number of 0 or more and 50 or less, and A indicates a linear or branched divalent saturated hydrocarbon group having 1 or more and 6 or less carbon atoms. ]

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

Further, R ₂ in the general formula (3) and the general formula (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 and toughness development, and preferably 25 or less, more preferably 25 or less from the viewpoint of reactivity and availability. It is 20 or less. Specifically, methyl group, ethyl group, propyl group, isopropyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, 2-ethylhexyl group, nonyl group, decyl group, undecyl group, dodecyl group, hexadecyl group. Examples thereof include a group, an octadecyl group, an isostearyl group, and an icosyl group.

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

A in the general formula (4) is a linear or branched divalent saturated hydrocarbon group having 1 or more and 6 or less 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 is preferably 2 or more from the viewpoint of availability and cost, and preferably 4 or less, more preferably 3 or less from the same viewpoint. Specifically, a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group and the like are exemplified, and among them, an ethylene group and a propylene group are preferable, and an ethylene group is more preferable.

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

The introduction of the above-mentioned substituent can be carried out according to a known method without particular limitation. Specifically, one or more compounds selected from an aromatic ring-containing oxide alkylene compound and an aromatic ring-containing glycidyl ether compound in the presence of a base with respect to a cellulosic raw material (referred to as "(b) compound"). And one or more compounds selected from the alkylene oxide compound represented by the following general formula (3A) and the glycidyl ether compound represented by the following general formula (4A) (referred to as "(a) compound"). Can be introduced simultaneously or separately via an ether bond. Here, the fact that the introduction of these compounds is "simultaneously or separately" means that the order of introduction of the compounds is not particularly limited in this embodiment, and for example, the introduction of the compound (a) and the compound (b) is carried out. It may be carried out at the same time, or (a) the compound may be introduced first and then the compound (b) may be introduced, or (b) the compound may be introduced first and then the compound (a) may be introduced. Means. In this aspect, from the viewpoint of mechanical strength and toughness development of the obtained resin composition, a method of (b) introducing the compound first and then (a) introducing the compound is preferable. Hereinafter, the details will be described by taking such a method as an example.

As the modified cellulose fiber into which the compound (b) has been introduced first, the one produced in the first aspect described above can be used regardless of the presence or absence of the miniaturization treatment.

As the compound for introducing the substituent represented by the general formula (3), for example, the alkylene oxide compound represented by the general formula (3A) is preferable. Such a compound may be prepared according to a known technique, 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, and 22 or less from the same viewpoint, from the viewpoint of mechanical strength and toughness expression of the obtained resin composition. It is preferably 18 or less, more preferably 14 or less, and further preferably 12 or less.

[In the formula, 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 of R ₂ in the general formula (3A) are the same as those in 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, 1. , 2-Epoxytetradecane, 1,2-epoxy octadecane and the like.

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

[In the formula, R ₂ represents hydrogen or a linear or branched alkyl group having 1 or more and 20 or less carbon atoms, n is a number of 0 or more and 50 or less, and A is a linear or branched chain having 1 or more and 6 or less carbon atoms. Shows the divalent saturated hydrocarbon group of. ]

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

N in the general formula (4A) indicates the number of moles of alkylene oxide added. 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 those in 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 glycidyl ether with polyoxyalkylene alkyl ether.

The amount of the compound represented by the general formula (3A) or 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. It can be determined by the desired introduction rate of the substituent represented by, but from the viewpoint of reactivity, it is preferably 0.01 equal amount or more, more preferably 0.1, or more with respect to the anhydrous glucose unit of the cellulosic raw material. Equal amount or more, more preferably 0.3 equal amount or more, further preferably 0.5 equal amount or more, still more preferably 1.0 equal amount or more, and preferably 10 equal amount or less from the viewpoint of manufacturing cost. It is more preferably 8 equal or less, still more preferably 6.5 equal or less, still more preferably 5 equal 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 carried out in the same manner as in the first aspect of the solvent. This can be done by mixing the two in the presence. The first aspect can be referred to for various conditions such as the type of solvent used, the amount used, the mixing conditions, and the reaction temperature.

After the reaction, post-treatment can be appropriately performed in order to remove unreacted compounds, bases and the like. As a method of the post-treatment, for example, an unreacted base can be neutralized with an acid (organic acid, inorganic acid, etc.), and then washed with an unreacted compound or a solvent in which the base dissolves. If desired, further drying (vacuum drying or the like) 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). A modified cellulose fiber having one or more substituents selected from the substituents represented by the general formula (4) introduced therein can be obtained.

[Modified cellulose fiber]
The modified cellulose fiber in the method of the second aspect has 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 It has a type crystal structure, and the specific structure can be represented by, for example, the general formula (6).

[In the formula, R is the same or different, hydrogen, a substituent selected from a substituent represented by the general formula (1) and a substituent represented by the general formula (2), or a substituent represented by the general formula (3). Indicates a substituent selected from the substituents to be used and the substituents represented by the general formula (4), where m preferably represents an integer of 20 or more and 3000 or less, except that all Rs are hydrogen at the same time. 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 at the same time, the substituent represented by the general formula (3) and the general formula ( Except when the substituent is selected from the substituents represented by 4). ]

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 crystallinity, and 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) are preferable. The range is the same as in the first aspect, and can be obtained by the same measuring method.

(Introduction rate)
Further, 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 the anhydrous glucose unit of the modified cellulose fiber in this embodiment is determined. It has a cellulose type I crystal structure, and from the viewpoint of mechanical strength and toughness development, it is preferably 1.5 mol or less, more preferably 1.0 mol or less, further preferably 0.8 mol or less, and preferably 0. It is 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, it is the total introduced molar ratio.

(Miniaturization processing)
The production method of the second aspect may include a step of refining the modified cellulose fiber into which the substituent is introduced as described above. As the miniaturization treatment, the treatment method described in the manufacturing method of the first aspect described above can be adopted.

Thus, the finely modified cellulose fiber produced by the method of this embodiment is obtained.

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

From the viewpoint of handleability, availability, and cost, the finely modified cellulose fiber is preferably 1 nm or more, more preferably 3 nm or more, further preferably 10 nm or more, further preferably 20 nm or more, and exhibiting mechanical strength and toughness. From this point of view, 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, still more preferably 120 nm or less.

[Resin composition]
The modified cellulose fiber produced by the method of the present invention has an excellent affinity with a low-polarity medium regardless of whether or not it has been subjected to a micronization treatment, and therefore is mixed with a known resin to form a resin composition. can do. Therefore, 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 resins in the resin composition are roughly divided into two, and will be 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.

Examples of the thermoplastic resin include 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; chloride. Examples thereof include vinyl resin; styrene resin; vinyl ether resin; polyvinyl alcohol resin; polyamide resin; polycarbonate resin; polysulfone resin and the like. As the curable resin, a photocurable resin and / or a thermosetting resin is preferable. Specific examples thereof include epoxy resin; (meth) acrylic resin; phenol resin; unsaturated polyester resin; polyurethane resin; or polyimide resin. These resins may be used alone or as a mixed resin of two or more kinds. In the present specification, the (meth) acrylic resin means a resin containing a methacrylic resin and an acrylic resin.

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

In the photocuring treatment, the 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-dialkylsion compounds, disulfide compounds, thiuram compounds, and fluoroamines. Examples include compounds. More specifically, 1-hydroxy-cyclohexyl-phenyl-ketone, 2-methyl-1 [4- (methylthio) phenyl] -2-morpholinopropane-1-one, benzylmethyl ketone, 1- (4-dodecyl). Examples thereof include phenyl) -2-hydroxy-2-methylpropan-1-one, 1- (4-isopropylphenyl) -2-hydroxy-2-hydroxy-2-methylpropan-1-one, and benzophenone.

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

When an epoxy resin is used as 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. The content of the curing agent may be appropriately set depending on the type of the curing agent used.

The resin in Aspect A is one selected from the group consisting of a thermoplastic resin, an epoxy resin, a (meth) acrylic resin, a phenol resin, an unsaturated polyester resin, a polyurethane resin, or a curable resin selected from 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, still more preferably 80% by mass, from the viewpoint of producing a molded product. % Or more, more preferably 85% by mass or more, and from the viewpoint of containing the modified cellulose fiber, preferably 99.5% by mass or less, more preferably 99% by mass or less, still more preferably 98% by mass or less, still more preferable. Is 95% by 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 mechanical strength and toughness development of the obtained resin composition. It is more preferably 2% by mass or more, still more preferably 5% by mass or more, and from the viewpoint of moldability and cost of the obtained resin composition, it is preferably 50% by mass or less, more preferably 40% by mass or less, still more preferably. It is 30% by mass or less, more preferably 20% by mass or less, still more preferably 15% by mass or less.

The amount of the modified cellulose fiber in the resin composition of Aspect A is preferably 0.5 part by mass or more, more preferably 0.5 part by mass or more, from the viewpoint of mechanical strength and toughness development of the obtained resin composition 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 preferably 100 parts by mass or less from the viewpoint of moldability and cost of the obtained resin composition. Is 70 parts by mass or less, more preferably 45 parts by mass or less, still more preferably 25 parts by mass or less, still more preferably 20 parts by mass or less.

The resin composition of Aspect A has, as other components other than the above, a compatibilizer; a plasticizer; a crystal nucleating agent; a filler (inorganic filler, an organic filler); a hydrolysis inhibitor; a flame retardant; an antioxidant. Lubricants that are hydrocarbon waxes and anionic surfactants; UV absorbers; Antistatic agents; Antifogging agents; Light stabilizers; Pigments; Antifungal agents; Antibacterial agents; Foaming agents; Surfactants; Starches , Polysaccharides such as alginic acid; Natural proteins such as gelatin, nikawa, casein; Inorganic compounds such as tannin, zeolite, ceramics, metal powder; Fragrance; Flow conditioner; Leveling agent; Conductive agent; Ultraviolet dispersant; Deodorant Agents and the like can be contained within a range that does not impair the effects of the present invention. Examples of the compatibilizer include compounds composed of a polar group having a high affinity for cellulose and a hydrophobic group having a high affinity for a resin. More specifically, examples of the polar group include maleic anhydride, maleic acid, and glycidyl methacrylate, and examples of the hydrophobic group include polypropylene, polyethylene, and the like. Similarly, it is also possible to add other polymer materials or other resin compositions within a range that does not impair the effects of the present invention. The content ratio of the arbitrary additive may be appropriately contained as long as the effect of the present invention is not impaired, but for example, it is preferably 20% by mass or less, more preferably about 10% by mass or less in the resin composition. More preferably, it is about 5% by mass or less.

The resin composition of Aspect A can be prepared without particular limitation as long as it contains the resin and the modified cellulose fiber, and contains, for example, the resin and the modified cellulose fiber, and if necessary, various additives. The raw material to be prepared can be agitated with a Henschel mixer or the like, or prepared by melt kneading or solvent casting using a known kneader such as a closed kneader, a single-screw or twin-screw extruder, or an open roll type kneader. ..

The method for producing the resin composition of Aspect A is particularly limited as long as it includes a step of mixing the resin and the finely modified cellulose fiber or a step of mixing the resin and the modified cellulose fiber and simultaneously making the fineness. Absent.
For example, the modified cellulose fiber obtained by the above-mentioned 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. Examples thereof include a step of mixing one or more kinds of resins selected from the group consisting of.
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 if necessary, various additives can be prepared by melt kneading or a solvent casting method using a known kneader. The conditions (temperature, time) for melt-kneading and solution mixing can be appropriately set according to a known technique according to the type of resin used.

Since the resin composition of the aspect A thus obtained is excellent in mechanical strength and toughness, it can be suitably used for various uses such as daily miscellaneous goods, home electric appliances, packing materials for home appliances, and automobile parts.

(Aspect B)
Further, in the present invention, a rubber-based resin can be used as the resin composition of the aspect B. As for rubber-based resins, carbon black compounded products are widely used as reinforcing materials in order to increase the strength, but it is considered that the reinforcing effect is also limited. However, in the present invention, it is considered that by blending the finely modified cellulose fiber of the present invention with the rubber-based resin, it becomes possible to provide a resin composition having excellent mechanical strength and toughness.

The rubber used in the present invention is not particularly limited, but a diene rubber is preferable from the viewpoint of reinforcing property. In addition to diene rubber, it can also be used for non-diene rubber such as urethane rubber, silicone rubber, and polysulfide rubber. As the diene rubber, 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), modified rubber and the like. 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), and styrene-butadiene copolymer rubber (from the viewpoint of achieving both good workability and high resilience of the rubber composition. One or more selected from SBR), chloroprene rubber (CR) and modified rubber is preferable, and selected from natural rubber (NR), styrene-butadiene copolymer rubber (SBR), chloroprene rubber (CR) and modified rubber. One kind or two or more kinds are more preferable. The diene rubber 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 content of rubber in the rubber composition of Aspect B is preferably 30% by mass or more, more preferably 45% by mass or more, still more preferably 55% by mass or more, from the viewpoint of molding processability of the composition. From the viewpoint of containing quality cellulose fibers 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, still more preferably 70% by mass or less.

The content of the modified cellulose fiber in the rubber composition of Aspect B is preferably 1% by mass or more, more preferably 2% by mass or more, still more preferably 5% by mass from the viewpoint of mechanical strength and toughness of the obtained 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 the aspect B is preferably 1 part by mass or more, more preferably 5 parts by mass or more, still more preferably 5 parts by mass or more, from the viewpoint of the obtained mechanical strength and toughness with respect to 100 parts by mass of the rubber. Is 10 parts by mass or more, more preferably 15 parts by mass or more, and from the viewpoint of operability during manufacturing, preferably 30 parts by mass or less, more preferably 25 parts by mass or less, still more preferably 20 parts by mass or less. Is.

The rubber composition of embodiment B contains, if desired, a reinforcing filler, a vulcanizing agent, a vulcanization accelerator, a vulcanization retarder, and aging, as long as the object of the present invention is not impaired. Conventional general amounts of various additives such as inhibitors, process oils, vegetable fats and oils, scorch inhibitors, zinc oxide, stearic acid, magnesium oxide, wax, phenolic resin, etc. for tires and other general rubbers. Can be blended with.

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

Examples of the vulcanizing agent include sulfur, sulfur compounds, oximes, nitroso compounds, polyamines, organic peroxides and the like. As the vulcanizing agent, only a single type may be used, or a plurality of types may be used in combination.

Examples of the vulcanization accelerator include guanidine-based, aldehyde-amine-based, aldehyde-ammonia-based, thiazole-based, sulfenamide-based, thiourea-based, thiuram-based, dithiocarbamate-based, and xanthate-based ones. As the vulcanization accelerator, only a single type may be used, or a plurality of types may be used in combination.

Examples of the sulfide retardant include aromatic organic acids such as salicylic acid, phthalic anhydride and benzoic acid, N-nitrosodiphenylamine, N-nitroso-2,2,4-trimethyl-1,2-dihydroquinone and N-. Examples thereof include nitroso compounds such as nitrosophenyl-β-naphthylamine. As the vulcanization retarder, only a single type may be used, or a plurality of types 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 ester-based agents. As the anti-aging agent, only a single type may be used, or a plurality of types may be used in combination.

Examples of the process oil include paraffin-based process oil, naphthenic-based process oil, and aromatic-based process oil. As the process oil, only one kind may be used, or a plurality of kinds may be used in combination.

Examples of vegetable oils and fats include castor oil, cottonseed oil, linseed oil, rapeseed oil, soybean oil, palm oil, palm oil, fallen raw oil, wood wax, rosin, and pine oil. As the vegetable oil or fat, only a single species may be used, or a plurality of species 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, modified cellulose fibers, and various additives if necessary, using, for example, an open kneader such as a roll, a closed kneader such as a Banbury mixer, or the like. it can. The temperature at the time of melting and mixing is usually 10 to 200 ° C, preferably 20 to 180 ° C. Alternatively, it may be prepared by preparing a solution in which rubber and modified cellulose fibers are dissolved using an organic solvent, and then removing the organic solvent component.

The method for producing the rubber composition of the aspect B is particularly limited as long as it includes a step of mixing the rubber and the finely modified cellulose fiber of the present invention, or a step of mixing the resin and the modified cellulose fiber and simultaneously making the fineness. There is no limit.
The target 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 batch, but it may be mixed in several times, and the raw materials may be added for 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 with the obtained mixture (kneading step B) may be performed. Further, 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 improving the dispersibility of various additives, the kneading is performed without mixing the vulcanizing agent. The kneading step C may be performed in the same manner as the conditions of the step A. The mixing can be carried out by a known method using, for example, an open kneader such as a roll, a closed kneader such as a Banbury mixer, or the like. Further, a rubber composition can also be obtained by dissolving the rubber with an organic solvent such as toluene, mixing the obtained rubber solution with the modified cellulose fiber, and then removing the organic solvent component by a drying step. ..

The rubber composition of Aspect B can be applied to various rubber product applications by using the rubber composition prepared by the above method, performing appropriate molding processing as necessary, and then vulcanizing or cross-linking. ..

Since the rubber composition of the aspect B is excellent in good mechanical strength and toughness, it can be suitably used for various uses such as daily miscellaneous goods, home electric appliances, automobile parts, and particularly for automobile applications.

Further, as a rubber product using the rubber composition of the aspect B, for example, an industrial rubber part will be described. Examples of industrial rubber parts include belts and hoses, and these include extruding the rubber composition of the present invention containing various additives as necessary according to the shape of each member at the unvulcanized stage. After forming unvulcanized rubber parts, various industrial rubber parts can be manufactured by heating and pressurizing in a vulcanizer. Improvements in basic performance, miniaturization and thinning of parts can be realized by improving mechanical strength, and durability can be improved by improving toughness.

Further, as a rubber product using the rubber composition of the aspect B, for example, in the case of producing a tire, the rubber composition of the present invention containing various additives as needed may be used in a tread or the like at the stage of unvulcanization. It is extruded according to the shape of each member of the tire, molded by a normal method on a tire molding machine, bonded together with other tire members to form an unvulcanized tire, and then heated in the vulcanizer. Tires can be manufactured under pressure. From the improvement of mechanical strength, it is possible to reduce the size and thickness of each member, and from the toughness, it is possible to improve the durability.

Hereinafter, the present invention will be specifically described with reference to Production Examples, Preparation Examples, Examples, Comparative Examples, and Reference Examples. It should be noted that these examples and the like are merely examples of the present invention and do not mean any limitation. The part in the example is a mass part unless otherwise specified. The "normal pressure" indicates 101.3 kPa, and the "room temperature" indicates 25 ° C.

Production Example 1 of Compound for Introducing Substituent <Production of Stearyl Glycidyl Ether>
In a 100 L reaction vessel, 10 kg of stearyl alcohol (Kao Corporation, Calcor 8098), 0.36 kg of tetrabutylammonium bromide (manufactured by Koei Chemical Industry Co., Ltd.), 7.5 kg of epichlorohydrin (manufactured by Dow Chemical Co., Ltd.), and 10 kg of hexane were charged, and nitrogen was added. Mixed in an atmosphere. While maintaining the mixed solution at 50 ° C., 12 kg of a 48 mass% sodium hydroxide aqueous solution (manufactured by Nankai Chemical Co., Inc.) was added dropwise over 30 minutes. After completion of the dropping, the mixture was further aged at 50 ° C. for 4 hours, and then washed with 13 kg of water 8 times to remove salts and alkalis. Then, the temperature in the tank was raised to 90 ° C., hexane was distilled off from the upper layer, and under reduced pressure (6.6 kPa), steam was further blown to remove the low boiling point compound. After dehydration, 8.6 kg of white stearyl glycidyl ether was obtained by distillation under reduced pressure at a tank temperature of 250 ° C. and a tank pressure of 1.3 kPa.

Preparation Example 1 of Modified Cellulose Fiber <Addition of Phenylglycidyl Ether>
Softwood bleached kraft pulp (denoted as "NBKP"; average fiber diameter 24 μm) was used as a cellulosic raw material.
First, to 5.0 g of absolutely dried NBKP, 3.0 g of N, N-dimethyl-4-aminopyridine (manufactured by Wako Pure Chemical Industry Co., Ltd., DMAP, 0.8 equivalent / AGU) and 20.0 g of acetonitrile (Wako Pure Chemical Industry Co., Ltd.) ) Was added and mixed uniformly, then 13.9 g of phenylglycidyl ether (manufactured by Tokyo Chemical Industry Co., Ltd., 3.0 eq / AGU) was added, sealed, and then allowed to stand at 70 ° C. for 24 hours. .. After the reaction, impurities are removed by thoroughly washing with toluene (manufactured by Wako Pure Chemical Industries, Ltd.) and acetone (manufactured by Wako Pure Chemical Industries, Ltd.), and further vacuum-dried at 70 ° C. overnight to have an aromatic substituent. A modified cellulose fiber (1) was obtained.

Preparation Examples of Modified Cellulose Fibers 2-5
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 etherifying agent and the amount charged were changed as shown in Table 1.

Preparation Example 6 of Modified Cellulose Fiber <Addition of Phenylglycidyl Ether>
As a cellulosic raw material, 5.0 g (as a solid content) of microfibrillated cellulose (denoted as "MFC") previously solvent-substituted with acetonitrile (manufactured by Daicel Fine Chem Ltd., "Cerish FD100-G", solid content concentration 10) The same method as in Preparation Example 2 of the modified cellulose fiber except that the content was changed to% by mass, average fiber diameter of 100 nm or less, cellulose content of 90% by mass, and water content of 3% by mass), and no additional solvent was added. A modified cellulose fiber (6) having an aromatic substituent was obtained by using.

Preparation Example 7 of Modified Cellulose Fiber <Aromatic Dual Graft>
To 5.0 g of the modified cellulose fiber (1), 4.1 g (1.1 equivalent / AGU) of DMAP and 50.0 g of acetonitrile were added and mixed uniformly, and then the stearyl obtained in Production Example 1 as an etherifying agent was obtained. 11.7 g (1.2 eq / AGU) of glycidyl ether was added, sealed, and then allowed to stand at 70 ° C. for 24 hours. After the reaction, impurities are removed by thoroughly washing with toluene and acetone, and further vacuum-dried 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 <Miniaturization 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 with a homogenizer (manufactured by Primix Corporation, TK Robomix) at 3000 rpm for 30 minutes, and then high pressure. A finely modified cellulose dispersion (solid content concentration 0.) in which finely divided modified cellulose fibers were dispersed in DMF by 10-pass treatment at 100 MPa with a homogenizer (“NanoVita L-ES” manufactured by Yoshida Machinery Co., Ltd.). 5% by mass) was prepared. The average fiber diameter of the refined modified cellulose fibers was 24 nm.

20 g of the obtained dispersion and 2.0 g of UV-3310B (manufactured by Nippon Synthetic Chemical Industry Co., Ltd.), which is a urethane acrylate resin, are mixed and mixed by using a high-pressure homogenizer for 1 pass at 60 MPa and 1 pass at 100 MPa. did. As a photopolymerization initiator, 0.08 g of 1-hydroxy-cyclohexyl-phenyl-ketone (manufactured by Wako Junyaku Co., Ltd.) is added, and the varnish is stirred for 7 minutes using a rotating and revolving stirrer Awatori Rentaro (manufactured by Shinky Co., Ltd.). Got The obtained varnish was coated with a bar coater to a coating thickness of 2 mm. The solvent was removed by drying at 80 ° C. for 120 minutes. Using a UV irradiation device (Made by Fusion Systems Japan, Light Hammer10), it is irradiated with 200 mJ / cm ² and photocured, and contains 5 parts by mass of modified cellulose fibers (100 parts by mass of acrylic resin), and has a thickness of about 0.1 mm. A sheet-shaped composite material molded product was produced.

Examples 2-4, Comparative Examples 1-2 <Miniaturization treatment and compounding with acrylic resin>
By performing the same treatment as in Example 1 except that the modified cellulose fiber used was changed to the modified cellulose fiber (2) to (6) in place of the modified cellulose fiber (1), respectively. A sheet-shaped composite material molded product having a thickness of about 0.1 mm was produced.

Reference example 1 <Acrylic resin blank>
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 except that 10 mL of DMF was used instead of the modified cellulose fiber dispersion and the coating thickness was changed to 0.5 mm. Manufactured the body.

Example 5 <Composite with rubber>
0.50 g of modified cellulose fiber (7) was put into 49.50 g of toluene, stirred with a homogenizer (manufactured by Primix Corporation, TK Robomix) at 3000 rpm for 30 minutes, and then a high-pressure homogenizer (manufactured by Yoshida Kikai Co., Ltd., By performing 10-pass treatment at 100 MPa with "NanoVita L-ES"), a modified cellulose dispersion (solid content concentration 1.0% by mass) in which finely divided modified cellulose fibers were dispersed in toluene was obtained. The average fiber diameter of the refined modified cellulose fibers was 15 nm. 10 g of the dispersion, 2.0 g of 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 rusulfene amine (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). The mixture was stirred for 2 hours. After confirming that it had dissolved, the obtained solution was finely treated with a high-pressure homogenizer for 1 pass at 60 MPa and 1 pass at 100 MPa. The obtained dispersion was finely treated with a glass chalet having a diameter of 9 cm. Toluene was removed at room temperature and normal pressure for 2 days. Then, the mixture was dried in a vacuum dryer (room temperature) for 12 hours and sulfided at 150 ° C. for 1 hour to sulfide having a thickness of about 0.2 mm. A rubber sheet was prepared.

Comparative Example 3 <Composite with rubber>
By performing the same treatment as in Example 5 except that the modified cellulose fiber used was changed to the modified cellulose fiber (8) instead of the modified cellulose fiber (7), 5 parts by mass of the modified cellulose fiber was obtained. 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 performing the same treatment as in Example 5 except that the modified cellulose fiber was not used.

With respect to the obtained modified cellulose fiber, the introduction rate of substituents, the average fiber diameter (including the average fiber diameter of the cellulosic raw material), and the confirmation of the crystal structure (crystallinity) were evaluated according to the methods of Test Examples 1 to 3. did. The mechanical properties of the molded product were evaluated according to the method of Test Example 4. The average fiber diameter of the finely divided 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 is determined by Analytical Chemistry, Vol. 51, No. The Zeisel method, which is known as a method for analyzing the average number of moles of alkoxy groups added to cellulose ether, described in 13, 2172 (1979), "15th revised Japanese Pharmacopoeia (section of analysis method for hydroxypropyl cellulose)" and the like. 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 volumetric flask was adjusted to the marked line with hexane to prepare an internal standard solution.
(Ii) 100 mg of the purified and dried modified cellulose fiber and 100 mg of adipic acid were precisely weighed in a 10 mL vial, and 2 mL of hydrogen iodide 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 tip.
(Iv) After heating, 3 mL of the internal standard solution and 3 mL of diethyl ether were sequentially injected into the vial, and the mixture was stirred at room temperature for 1 minute.
(V) The upper layer (diethyl ether layer) of the mixture separated into 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: Agilent Technologies DB-5 (12 m, 0.2 mm x 0.33 μm)
Column temperature: 100 ° C → 10 ° C / min → 280 ° C (10 min Hold)
Injector temperature: 300 ° C, detector temperature: 300 ° C, driving amount: 1 μL
The content (mass%) of the ether group 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 and the like.

From the obtained ether group content, the molar substitution degree (MS) (molar amount of substituents per 1 mol of anhydrous glucose unit) was calculated using the following mathematical formula (1).
(Formula 1)
MS = (W1 / Mw) / ((100-W1) /162.14)
W1: Content of ether group in modified cellulose fiber (mass%)
Mw: Molecular weight of the introduced etherifying agent (g / mol)

Test Example 2 (Average fiber diameter of modified cellulosic fiber and cellulosic raw material)
The fiber diameters of the modified cellulose fiber and the cellulosic raw material were determined by the following method.
Approximately 0.3 g of the absolutely dried sample was precisely weighed and stirred in 1.0 L of ion-exchanged water using a household mixer for 1 minute to dissolve the fibers in the water. Then, 4.0 L of ion-exchanged water was further added, and the mixture was stirred until uniform. About 50 g of the obtained aqueous dispersion was recovered as a measuring solution and weighed precisely. The obtained measurement liquid was analyzed by "Kajaani Fiber Lab" manufactured by Metso Automation Co., Ltd. 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 a "Rigaku RINT 2500VC X-RAY differential tometer" manufactured by Rigaku.
The measurement conditions were X-ray source: Cu / Kα-radiation, tube voltage: 40 kv, tube current: 120 mA, measurement range: diffraction angle 2θ = 5 to 45 °, and X-ray scan speed: 10 ° / min. The measurement sample was prepared by compressing pellets having an area of 320 mm ² × thickness of 1 mm. 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)
[In the formula, I22.6 is the diffraction intensity of the lattice plane (002 plane) (diffraction angle 2θ = 22.6 °) in X-ray diffraction, and I18.5 is the amorphous portion (diffraction angle 2θ = 18.5 °). Diffraction intensity]

Test Example 4 (tensile modulus)
In a thermostatic chamber at 25 ° C., a tensile compression tester (“Autograph AGS-X” manufactured by SHIMADZU) was used to measure the tensile elastic modulus of the molded product by a tensile test in accordance with JIS K7113. Three samples were prepared by punching out any three parts of the molded product with a No. 2 dumbbell. Each sample was set at a distance between fulcrums 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", (the average elastic modulus of the three samples at 89.5-90.5% elongation at break). Ratio) / (average elastic modulus of three samples at 0.5-1.5% modulus of elongation at break) was defined as "elastic retention rate". The higher the initial elastic modulus, the better the mechanical strength at low strain, and the higher the elastic modulus, the better the mechanical strength at low strain is maintained up to the high strain region, that is, the toughness is excellent. Show that.

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

From Tables 2 and 3, it can be seen that by compounding the modified cellulose fiber obtained by the production method of the present invention with a resin, high mechanical strength and toughness can be exhibited in a wide range of application regardless of the type of resin. .. In particular, Comparative Example 2 corresponds to the technique of Patent Document 1 described in the column of background technology, in which the cellulose fibers are refined and then etherified to obtain modified cellulose fibers. Compared with Example 1 using the same etherifying agent as Comparative Example 2, it can be seen that Example is remarkably 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 high mechanical strength and toughness, daily miscellaneous goods, home appliance parts, packing materials for home appliance parts, It can be suitably used for various industrial applications such as automobile parts.

Claims (6)

In the presence of a base, one or more compounds selected from an aromatic ring-containing oxide alkylene compound and an aromatic ring-containing glycidyl ether compound are introduced into a cellulosic raw material via an ether bond, and then miniaturized. A method for producing modified cellulose fibers.
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 type I crystal structure.
-CH _2- CH (OH) -R ₁ (1)
-CH _2- CH (OH) -CH _2- (OA) _n- O-R ₁ (2)
[In the formula, R ₁ in the general formula (1) and the general formula (2) each independently represents a functional group having at least one aromatic ring and having 6 to 30 carbon atoms, and n in the general formula (2). Indicates a number of 0 or more and 50 or less, and A indicates a linear or branched divalent saturated hydrocarbon group having 1 or more and 6 or less carbon atoms. ] A resin composition containing a modified cellulose fiber and a resin obtained by the production method according to claim 1. One or more modified cellulose fibers having an average fiber diameter of 5 μm or more and selected from the substituents represented by the following general formula (1) and the substituents represented by the following general formula (2). A modified cellulose fiber having a cellulose type I crystal structure in which the substituent of the above is 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)
[In the formula, R ₁ in the general formula (1) and the general formula (2) each independently represents a functional group having at least one aromatic ring and having 6 to 30 carbon atoms, and n in the general formula (2). Indicates a number of 0 or more and 50 or less, and A indicates a linear or branched divalent saturated hydrocarbon group having 1 or more and 6 or less carbon atoms. ] One or more substituents selected from the substituents represented by the following general formula (1) and the substituents represented by the following general formula (2), and the substitutions represented by the following general formula (3). A modified cellulose fiber having a cellulose type I crystal structure in which one or more substituents selected from the group and the substituent represented by the following general formula (4) 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)
[In the formula, R ₁ in the general formula (1) and the general formula (2) each independently represents a functional group having at least one aromatic ring and having 6 to 30 carbon atoms, and n in the general formula (2). Indicates a number of 0 or more and 50 or less, and A indicates a linear or branched divalent saturated hydrocarbon group having 1 or more and 6 or less carbon atoms. ]
-CH _2- CH (OH) -R ₂ (3)
-CH _2- CH (OH) -CH _2- (OA) _n- O-R ₂ (4)
[In the formula, R ₂ in the general formula (3) and the general formula (4) independently represent a hydrogen or a linear or branched alkyl group having 1 to 20 carbon atoms, and n in the general formula (4). Indicates a number of 0 or more and 50 or less, and A indicates a linear or branched divalent saturated hydrocarbon group having 1 or more and 6 or less carbon atoms. ] One or more compounds selected from an aromatic ring-containing oxide alkylene compound and an aromatic ring-containing glycidyl ether compound, and an oxide alkylene compound represented by the general formula (3A) and a general formula with respect to a cellulosic raw material in the presence of a base. A method for producing a modified cellulose fiber, wherein one or more compounds selected from the glycidyl ether compounds shown in (4A) are introduced via an ether bond.
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), and the following general formula ( One or more substituents selected from the substituent represented by 3) and the substituent represented by the following general formula (4) are bonded to the cellulose fiber via an ether bond to form a cellulose type I crystal structure. A method for producing a modified cellulose fiber.
-CH _2- CH (OH) -R ₁ (1)
-CH _2- CH (OH) -CH _2- (OA) _n- O-R ₁ (2)
[In the formula, R ₁ in the general formula (1) and the general formula (2) each independently represents a functional group having at least one aromatic ring and having 6 to 30 carbon atoms, and n in the general formula (2). Indicates a number of 0 or more and 50 or less, and A indicates a linear or branched divalent saturated hydrocarbon group having 1 or more and 6 or less carbon atoms. ]
-CH _2- CH (OH) -R ₂ (3)
-CH _2- CH (OH) -CH _2- (OA) _n- O-R ₂ (4)

[In the formula, R ₂ in the general formulas (3), (3A), (4) and (4A) independently represent hydrogen or a linear or branched alkyl group having 1 to 20 carbon atoms, and is generally used. In the formulas (4) and (4A), n is a number of 0 or more and 50 or less, and A is a linear or branched divalent saturated hydrocarbon group having 1 or more and 6 or less carbon atoms. ] A resin composition containing 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.