JP6547414B2 - Modified cellulose fiber-containing resin composition, molding material and molding - Google Patents

Description

The present invention relates to a modified cellulose fiber-containing resin composition suitable for molding material applications, and more particularly, a modified cellulose fiber-containing resin composition capable of dramatically improving the strength of a molded product when used as a reinforcing material for the molded product. About.

Heretofore, carbon fibers, glass fibers and the like have been widely and generally used as reinforcing materials used for molding material resins. However, carbon fibers are not suitable for thermal recycling and are expensive because they are hard to burn. In addition, glass fiber is relatively inexpensive, but there is a problem in disposal in thermal recycling.

On the other hand, cellulose fibers obtained from plant fibers are relatively inexpensive and excellent in thermal recycling. In addition, it has attracted attention as a filler for fiber reinforced resins because it has the same strength at a light weight of one-fifth of steel.

However, since cellulose fibers have low reactivity with resins for molding materials and curing agents, and dispersibility in resins for molding materials is low, when cellulose fibers are added to resins for molding materials, cellulose fibers and resins for molding materials are There is a problem that adhesive strength falls at the interface of As a result, the reinforcing effect of the cellulose fiber is not expressed, and conversely, the mechanical strength such as bending strength is reduced.

In order to improve the dispersibility of cellulose fibers in resins for molding materials, it is an attempt to use compatibilizers, to modify cellulose fibers, or to use defibration resins. Is being done.

For example, as described in Patent Document 1 etc., using a maleic acid-modified polypropylene as a compatibilizer or interface reinforcing agent in a composite material comprising a cellulose microfibrillated vegetable fiber and a polyolefin such as polypropylene It is widely known.

Patent Document 2 discloses a natural fiber composite composition which is excellent in dispersibility of natural fibers in a thermoplastic polymer, molding processability, strength of moldings, hue of moldings, and moreover hardly has odor of moldings, and moldings thereof. The use of terpene resins, petroleum resins, rosin resins and the like as dispersing resins is described for the purpose of obtaining the resin.

Moreover, in patent document 3, in order to improve the mechanical strength of the obtained molding material, a thermoplastic resin or a thermosetting resin and a modified vegetable fiber obtained by being modified with alkyl or alkenyl succinic anhydride are used as organic liquids. It is described that the microfibrillated plant fibers are uniformly dispersed in the highly hydrophobic resin by mixing in the presence.

On the other hand, in Patent Documents 4 and 5, a fiber reinforced resin is obtained by using, as a reinforcing material, cellulose nanofibers obtained by directly refining cellulose in a fibrillation resin without using water or an organic solvent. A reinforced matrix resin for fiber reinforced resins is described which can increase the strength of the composite.

U.S. Patent Publication No. 2008/0146701 JP, 2012-111855, A International Publication No. 2013/133093 International Publication No. 2013/122209 JP, 2013-116928, A

By using any of the above methods, the mechanical strength of the molded body is improved as compared to the case where no reinforcing material is used. However, since the dispersibility of the cellulose fiber in the resin is still insufficient, sufficient strength and elastic modulus can not be obtained.

The object of the present invention is to provide a modified cellulose fiber-containing resin composition excellent in dispersibility and mechanical strength to a resin for molding material, a molding material containing the modified cellulose fiber-containing resin composition, and a molded article thereof. Do.

As a result of intensive studies, the inventors of the present invention have found that a modified cellulose fiber in which a specific acid anhydride having a hydrophobic group is added in advance to a hydroxyl group on the surface of the cellulose fiber to increase the hydrophobicity of the cellulose fiber. By kneading with a specific dispersion resin having a softening point to refine the cellulose fiber, it is found that the mechanical strength of the molded product can be remarkably improved when it is used as a reinforcing material for the molded product. The present invention has been completed.

That is, the present invention
(1) A modified cellulose fiber (A) obtained by adding and esterifying a cyclic polybasic acid anhydride (a) having a carbon number of 15 or more having a hydrophobic group to a cellulose fiber and containing a dispersing resin (B) A modified cellulose fiber-containing resin composition, which is a modified cellulose fiber-containing resin composition and satisfies the following (i) and (ii).
(I) At least one selected from petroleum resins and coal resins having a softening point of 135 ° C. or less (ii) The modified cellulose fiber (A) and a resin for dispersion (B) (2) The content of the modified cellulose fiber (A) is 20 to 70% by mass in 100% by mass of the modified cellulose fiber-containing resin composition (1) The modified cellulose fiber containing resin composition as described in 4.).
(3) A molding material containing the modified cellulose fiber-containing resin composition according to the above (1) or (2) and a resin for molding material (C).
(4) The molding material as described in said (3) whose said resin (C) for molding materials is polyolefin.
(5) A molded product produced from the molding material described in the above (3) or (4).
(6) The manufacturing method of the modified cellulose fiber containing resin composition as described in said (1) or (2).
It is.

The modified cellulose fiber-containing resin composition of the present invention is a modified cellulose fiber (A) obtained by esterifying a cyclic polybasic acid anhydride (a) having a carbon number of 15 or more having a hydrophobic group to a cellulose fiber, The modified cellulose fiber (A) is a resin containing a dispersing resin (B), and the dispersing resin (B) is at least one selected from petroleum resins and coal resins having a softening point of 135 ° C. or less. And the dispersion resin (B) are kneaded to knead the modified cellulose fiber (A). Therefore, when it is used as a reinforcing material for a molded product, it has a mechanical strength remarkably excellent. You can get the body.

The modified cellulose fiber (A) used in the present invention is a cyclic polybasic acid anhydride (a) having a hydrophobic group and having 15 or more carbon atoms (hereinafter referred to simply as "cyclic polybasic acid anhydride (a)", Acid anhydride (also referred to as "a)" is obtained by adding to cellulose fiber.

The cellulose fiber that can be used to obtain the modified cellulose fiber (A) is not particularly limited, but for example, a plant-derived fiber contained in wood, bamboo, hemp, jute, kenaf, cotton, beet etc., the plant Pulp obtained from fibers derived from cellulose, cellulose fiber treated with mercerization, regenerated cellulose fiber such as rayon, cellophane, lyocell, acid anhydride modified cellulose, etc. may be mentioned. Among these, as a preferable cellulose fiber raw material, a wood is mentioned, For example, a sitka spruce, a cedar, a cypress, eucalyptus, acacia etc. are mentioned. Then, pulp or paper obtained from these as raw materials or those obtained by disintegrating waste paper are suitably used as cellulose fibers. The cellulose fiber may be used alone or in combination of two or more selected from these.

As the pulp, for example, chemical pulp (kraft pulp (KP), sulfite pulp (SP)) obtained by pulping the plant raw material chemically or mechanically, or both in combination, semi-chemical Pulp (SCP), chemigrand pulp (CGP), chemimechanical pulp (CMP), ground pulp (GP), refiner mechanical pulp (RMP), thermomechanical pulp (TMP), chemithermomechanical pulp (CTMP), etc. may be mentioned. .

The cellulose fiber does not significantly affect the reactivity with the cyclic polybasic acid anhydride (a) having 15 or more carbon atoms having a hydrophobic group, the degree of substitution, the compatibility with a resin, etc., and the desired mechanical strength As long as there is no problem in obtaining a molded product having the above, one having a hydroxyl group partially substituted by a hydroxyl group esterified or a functional group such as a carboxyl group may be used. In addition, water contained in the cellulose fiber is substituted in advance with a solvent such as toluene or N-methylpyrrolidone so as not to inhibit the reaction with the cyclic polybasic acid anhydride (a) having 15 or more carbon atoms having a hydrophobic group. It is preferable to keep the

The cyclic polybasic acid anhydride (a) having 15 or more carbon atoms having a hydrophobic group used in the present invention has a hydrophobic group in the main chain and / or side chain of the cyclic polybasic acid anhydride, and carbon The number is not particularly limited as long as it is 15 or more, but 20 or more is preferable. If the carbon number is less than 15, the compatibility of the modified cellulose fiber (A) with the resin can not be improved, and as a result, the mechanical strength of the molded article can not be improved. The upper limit of the number of carbons in the cyclic polybasic acid anhydride (a) having 15 or more carbon atoms having a hydrophobic group is not particularly limited, but, for example, 1500 is preferable, 200 is more preferable, and 30 is still more preferable. preferable. When the carbon number exceeds 1,500, it is difficult to knead the resin for dispersion of the modified cellulose fiber (A) to be obtained and the resin for molding material, and the dispersion of the modified cellulose fiber (A) becomes insufficient, and a molded article May reduce the mechanical strength of the

The cyclic polybasic acid anhydride (a) has a hydrophobic group in the main chain and / or side chain of the cyclic polybasic acid anhydride.

As the cyclic polybasic acid anhydride, if dehydration and condensation takes place in the same molecule of polybasic acid or between two or more polybasic acids, a cyclic structure is formed. It is not particularly limited. Among them, polybasic acid anhydrides in which dehydration condensation occurs in the same molecule of polybasic acid to form a cyclic structure are preferable.

Examples of the polybasic acids include tribasic acids such as aconitic acid and trimellitic acid; and dibasic acids such as succinic acid, itaconic acid, maleic acid, fumaric acid and citraconic acid. Among them, dibasic acids are preferable, dicarboxylic acids such as succinic acid, itaconic acid, maleic acid, fumaric acid and citraconic acid are more preferable, and succinic acid and maleic acid are more preferable.

Examples of the cyclic polybasic acid anhydrides include cyclic carboxylic acid anhydrides having 4 to 10 carbon atoms (preferably 4 to 6) such as succinic anhydride, maleic anhydride, citraconic anhydride, itaconic anhydride, etc. It can be mentioned. Among these, succinic anhydride and maleic anhydride are preferably used from the viewpoint of easiness of reaction with a hydrophobic group because polybasic acid anhydride itself has poor homopolymerizability.

The hydrophobic group contained in the cyclic polybasic acid anhydride (a) is not particularly limited as long as it has hydrophobicity, and examples thereof include a hydrocarbon group and a petroleum resin.
The hydrocarbon group may be linear or branched, but is preferably linear from the viewpoint of the hydrophobicity of the cyclic polybasic acid anhydride (a).
The carbon number of the hydrocarbon group is preferably 11 or more, more preferably 16 or more. The carbon number of the hydrocarbon group is preferably 1,500 or less, more preferably 200 or less, and still more preferably 26 or less. When the carbon number of the hydrocarbon group is within the above range, the cyclic polybasic acid anhydride (a) can be provided with an appropriate hydrophobicity, so that the effects of the present invention can be more suitably obtained.

As said hydrocarbon group, an alkyl group, an alkenyl group, an alkynyl group etc. are mentioned, for example. Among them, an alkenyl group is more preferable because it can impart appropriate hydrophobicity to the cyclic polybasic acid anhydride (a).

Examples of the alkenyl group include dodecenyl group, hexadecenyl group and octadecenyl group. Among these, hexadecenyl group and octadecenyl group are preferable because cyclic polybasic acid anhydride (a) can be provided with appropriate hydrophobicity.

On the other hand, the case where the hydrophobic group contained in the cyclic polybasic acid anhydride (a) is a petroleum resin means that the cyclic polybasic acid anhydride (a) is an acid anhydride group-containing petroleum resin. The petroleum resin and the acid anhydride group-containing petroleum resin will be described later.

Examples of the cyclic polybasic acid anhydride (a) having 15 or more carbon atoms having a hydrophobic group include dodecenyl succinic anhydride, hexadecenyl succinic anhydride, octadecenyl succinic anhydride, etc. And a cyclic carboxylic acid anhydride having a hydrocarbon group and having a carbon number of 15 or more; an acid anhydride group-containing petroleum resin and the like.
In addition, as a kind of cyclic polybasic acid anhydride (a) having 15 or more carbon atoms having a hydrophobic group to be used, in the case of mixing the modified cellulose fiber-containing resin composition of the present invention with a resin for molding material described later According to the kind of resin for molding materials, a suitable thing should just be selected suitably. For example, when using polyolefin as resin for molding materials, the cyclic-carboxylic-acid anhydride which has 15 or more carbon atoms which has the said hydrocarbon group as an acid anhydride (a) is used suitably.

The acid anhydride group-containing petroleum resin is a petroleum resin having an acid anhydride ring obtained by grafting a cyclic polybasic acid anhydride to the petroleum resin, and is a resin having a carbon number of 15 or more, and is publicly known. It is obtained by grafting reaction. For example, petroleum resin and cyclic polybasic acid anhydride (for example, maleic anhydride) can be obtained by grafting with an organic peroxide and purification. In the grafting reaction, an organic solvent which does not react with the cyclic polybasic acid anhydride may be used. From the change of the acid value after the reaction purification with respect to the petroleum resin before the reaction, it can be confirmed that the resin is an acid anhydride group-containing petroleum resin.

Examples of the petroleum resin include C5 petroleum resin, C9 petroleum resin, C5C9 petroleum resin, dicyclopentadiene resin, hydrides thereof, and the like, and one or more of these may be used in combination. Can.

The cyclic polybasic acid anhydride used to obtain the acid anhydride group-containing petroleum resin is not particularly limited as long as a petroleum resin having an acid anhydride ring can be obtained by grafting to the petroleum resin, In order to advance the grafting reaction, any one having a carbon-carbon unsaturated bond may be used, for example, one having 4 to 10 (preferably 4 to 6) carbon atoms such as maleic anhydride, citraconic anhydride, itaconic anhydride and the like A carbon-carbon unsaturated bond containing cyclic carboxylic acid anhydride etc. are mentioned. Among these, maleic anhydride is preferably used from the viewpoint of the grafting reactivity with a petroleum resin.

Furthermore, as the organic peroxide, for example, t-butyl peroxide, t-butylperoxypivalate, dilauroyl peroxide, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanate , T-butylperoxy-2-ethylhexanate, dibenzoyl peroxide, t-butylperoxylaurate, dicumyl peroxide, di-t-hexyl peroxide, etc., among which dialkyl peroxides can be used. And dicumyl peroxide are preferably used. Further, as the organic solvent, for example, saturated aliphatic hydrocarbons such as hexane, heptane, octane and the like, saturated alicyclic hydrocarbons such as cyclohexane, methylcyclohexane, ethylcyclohexane, cycloheptane, methylcycloheptane and the like, Aromatic hydrocarbons containing no ethylenic double bond such as toluene, xylene and ethylbenzene, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, alkylene glycol alkyl ether alkylates such as propylene glycol monomethyl ether acetate, diethylene glycol Dialkylene glycol alkyl ether alkylate such as monoethyl ether acetate, diethylene glycol monobutyl ether acetate, ethyl acetate, And alkyl alkylates such as propyl acetate, butyl acetate, ethyl propionate, propyl propionate and butyl propionate, and the like, and alkyl alkylates, alkylene glycol alkyl ether alkylates, dialkylene glycol alkyl ether alkylates among others It is preferably used.

The molecular weight of the acid anhydride group-containing petroleum resin is not particularly limited, but it is preferably 400 to 20,000 in terms of polystyrene equivalent weight average molecular weight measured by gel permeation chromatography, more preferably 500 to 9000, still more preferably 600 to 6000 It is. If the weight average molecular weight is less than 400, the compatibility of the modified cellulose fiber (A) with the resin can not be improved, and as a result, the mechanical strength of the molded product may be reduced. In addition, when the weight average molecular weight exceeds 20000, the viscosity of the resin is usually increased, so that it is difficult to knead the resin for dispersion of the modified cellulose fiber (A) to be obtained and the resin for molding material, and modified cellulose fiber Dispersion of (A) may be insufficient, which may reduce the mechanical strength of the molded body.

The modified cellulose fiber (A) is obtained by adding a cyclic polybasic acid anhydride (a) having a carbon number of 15 or more having a hydrophobic group to a cellulose fiber and esterifying (modification reaction), The method of the esterification reaction is not particularly limited, and the esterification reaction can be carried out by a method which is usually carried out, for example, any of the following methods. The obtained modified cellulose fiber (A) can be usually used for production of a modified cellulose fiber-containing resin composition by filtering, washing with water, etc. to remove the solvent, catalyst and the like.
(I) Cyclic polybasic acid anhydride (a) having 15 or more carbon atoms having a hydrophobic group is sequentially or collectively added to a dispersion liquid in which solvent-substituted cellulose fibers are dispersed, to cause a reaction.
(II) A cyclic polybasic acid anhydride (a) having a carbon number of 15 or more having a melted hydrophobic group and a cellulose fiber are mixed and reacted.

The addition rate of the acid anhydride (a) to the cellulose fiber is preferably 5 to 150% by mass, and more preferably 10 to 100% by mass, in consideration of the addition efficiency and the resin affinity.
In addition, the addition rate with respect to the cellulose fiber of the said acid anhydride (a) can be calculated by the calculation method performed in the Example mentioned later.

The dispersing resin (B) used in the present invention is at least one selected from petroleum resins and coal resins having a softening point of 135 ° C. or less in a ring and ball test in accordance with JIS K2207. When the softening point exceeds 135 ° C., it is difficult to knead the modified cellulose fiber (A) to the resin for molding material to be a matrix when preparing a molding material containing the modified cellulose fiber-containing resin composition, and the dispersion is not As a result, the mechanical strength of the molded body is reduced. In addition, when the softening point is less than 40 ° C., the softening point of the molding material itself may be lowered, and the mechanical strength of the molded body may be lowered. As a softening point of the resin (B) for dispersion | distribution, 120 degrees C or less is preferable, and 110 degrees C or less is more preferable. On the other hand, the softening point is preferably 40 ° C. or more, more preferably 60 ° C. or more, and still more preferably 80 ° C. or more from the viewpoint of dispersibility.

The molecular weight of the dispersing resin (B) is not particularly limited, but it is preferably 200 to 20,000 in terms of polystyrene-equivalent weight average molecular weight measured by gel permeation chromatography, more preferably 300 to 9000, still more preferably 500 to 3000. . When the weight average molecular weight is less than 200, plasticization of the molding material and generation of air bubbles during molding may be caused, and as a result, the mechanical strength of the molded body may be reduced. In addition, when the weight average molecular weight exceeds 20000, the viscosity of the resin usually increases, so depending on the composition of the dispersing resin (B), it is difficult to knead with the modified cellulose fiber (A) and the resin for molding material, Dispersion of the cellulose fibers (A) may be insufficient, which may reduce the mechanical strength of the molded body.

Examples of the petroleum resins include C5 petroleum resins, C9 petroleum resins, C5 C9 petroleum resins, dicyclopentadiene resins, hydrides thereof, and cyclic polybasic acid anhydrides thereto (for example, maleic anhydride) And modified products added with an acid).

Examples of the coal-based resin include coumarone resins, coumarone indene resins, hydrides thereof, and modified products obtained by adding cyclic polybasic acid anhydride (for example, maleic anhydride) to these.

Among them, petroleum resins are particularly preferable as the dispersing resin (B), and the modified cellulose fiber-containing resin composition of the present invention has the above-described hydrocarbon group-containing carbon number of 15 or more from the viewpoint of compatibility. The most preferable is one containing a modified cellulose fiber (A) modified with a cyclic carboxylic acid anhydride of the above and a dispersing resin (B) which is a petroleum resin.

Moreover, as long as the effects of the present invention are not impaired, the modified cellulose fiber-containing resin composition of the present invention includes other components as long as the modified cellulose fiber (A) and the dispersing resin (B) are contained. For example, a resin having a softening point of 135 ° C. or less other than the dispersing resin (B) may be mixed with the dispersing resin (B) and used. As such resin, terpene resin, rosin resin, etc. are mentioned. When these resins are mixed with the dispersing resin (B) and used, the blending amount thereof is preferably 50% by mass or less with respect to the total amount of the resin and the dispersing resin (B).

Examples of terpene resins that can be used by mixing with the dispersing resin (B) include α-pinene resin, β-pinene resin, terpene phenol resin, aromatic modified terpene resin, and hydrides thereof, And modified products obtained by adding maleic anhydride to these.

Examples of rosin resins that can be used by mixing with the dispersing resin (B) include gum rosin, wood rosin, tall rosin, and hydrogenated rosin, disproportionated rosin, and maleic acid-modified rosin using the rosin as a raw material. And fumaric acid modified rosin, (meth) acrylic acid modified rosin, esterified rosin condensed with alcohol, and phenol modified rosin.

Furthermore, 20 mass% or less resin (C) for below-mentioned molding materials with respect to a total of 100 mass% of modified cellulose fiber (A) and resin for dispersions (B) in the range which does not impair the effect of the present invention The modified cellulose fiber-containing resin composition of the present invention can also be constituted by simultaneously kneading the modified cellulose fiber (A) and the dispersing resin (B).

The modified cellulose fiber-containing resin composition of the present invention is obtained by kneading the modified cellulose fiber (A) and the dispersing resin (B) to refine the modified cellulose fiber (A). That is, a method for producing a modified cellulose fiber-containing resin composition containing modified cellulose fiber (A) and a dispersing resin (B), wherein the modified cellulose fiber (A) has a hydrophobic group in the cellulose fiber It is obtained by adding and esterifying a cyclic polybasic acid anhydride (a) having 15 or more carbon atoms, and the dispersion resin (B) is a petroleum resin and a coal resin having a softening point of 135 ° C. or less. The method for producing a modified cellulose fiber-containing resin composition, comprising the step of kneading the modified cellulose fiber (A) and the dispersing resin (B). Is also one of the present invention.
Here, in the present specification, that the modified cellulose fiber (A) is refined means that the modified cellulose fiber (A) is disintegrated, specifically, the modified cellulose fiber is in the width direction It means being disintegrated to 5 μm or less. The defibrated state of the fiber can be observed by the method carried out in the examples described later.

As described later, since the content of the modified cellulose fiber-containing resin composition in the molding material is appropriately adjusted, the content ratio of the modified cellulose fiber (A) in the modified cellulose fiber-containing resin composition is not particularly limited. 20-70 mass% is preferable in 100 mass% of fiber containing resin compositions. If the content of the modified cellulose fiber (A) is less than 20% by mass, the proportion of the dispersing resin (B) in forming the molding material becomes excessively large, which may deteriorate the mechanical strength of the molded body. When the content of the modified cellulose fiber (A) exceeds 70% by mass, the dispersibility of the modified cellulose fiber (A) in the molding material when used as a molding material is extremely reduced, and the mechanical strength as a molded body is sufficient. There is a risk that can not be obtained. The content of the modified cellulose fiber (A) is preferably 25% by mass or more, more preferably 30% by mass or more, and most preferably 45% by mass or more in 100% by mass of the modified cellulose fiber-containing resin composition. On the other hand, 60 mass% or less is more preferable, and 55 mass% or less is still more preferable.

The step of kneading the modified cellulose fiber (A) and the dispersing resin (B) is not particularly limited as long as the modified cellulose fiber (A) and the dispersing resin (B) are kneaded, and is usually performed. For example, the modified cellulose fiber (A) is dispersed in the dispersing resin (B) in the kneader, stirred and mixed under strong shear force, and the modified cellulose fiber (A) is It is preferable that the process be miniaturized. Examples of kneaders that can be used in the kneading step include a two-roll mill, a three-roll mill, a single-screw extrusion kneader, a twin-screw extrusion kneader, a Banbury mixer, a pressure kneader, and the like. Although it can be used singly or in combination of two or more, it is not limited thereto. In order to promote refinement of the modified cellulose fiber (A), it is preferable to use a twin-screw extrusion kneader, a Banbury mixer, and a pressure kneader.
The kneading conditions such as the kneading temperature and the kneading time in the kneading step are appropriately set so that the modified cellulose fiber (A) and the dispersing resin (B) can be sufficiently kneaded and the modified cellulose fiber (A) can be refined. Just do it.

The modified cellulose fiber-containing resin composition of the present invention can be used as it is as a molding material as it is, as described above, for processing of a molded product, but usually, the modified cellulose fiber-containing resin composition is further used as a resin for any molding material Dilute to an arbitrary ratio in (C), melt and knead, and use as a molding material. Thus, a molding material containing the modified cellulose fiber-containing resin composition of the present invention, or a molding material containing the modified cellulose fiber-containing resin composition of the present invention and a resin for molding material (C) is also the present invention. It is one of the

Here, when the molding material of the present invention includes the resin for molding material (C) in addition to the modified cellulose fiber-containing resin composition of the present invention, the modified cellulose fiber ( A) and the dispersing resin (B) are kneaded to produce the modified cellulose fiber-containing resin composition of the present invention, and then the modified cellulose fiber-containing resin composition and the resin for molding material (C) It is preferable to knead and manufacture. By using such a manufacturing method, it becomes possible to significantly improve the mechanical strength of the molded body obtained from the molding material, while, for example, the modified cellulose fiber (A) and the dispersing resin (B) And when resin (C) for molding materials is prepared collectively and knead | mixed and it is set as a molding material, the molded object obtained from the said molding material may become insufficient in mechanical strength.
Thus, a method for producing a molding material containing the modified cellulose fiber-containing resin composition containing the modified cellulose fiber (A) and the dispersing resin (B), and the resin for molding material (C), The modified cellulose fiber (A) is obtained by adding and esterifying a cyclic polybasic acid anhydride (a) having 15 or more carbon atoms having a hydrophobic group to a cellulose fiber, and the dispersion resin (B) is And at least one selected from petroleum-based resins and coal-based resins having a softening point of 135 ° C. or less, and the production method comprises kneading the modified cellulose fiber (A) and the dispersing resin (B) And a step of obtaining a modified cellulose fiber-containing resin composition, and a step of kneading the obtained modified cellulose fiber-containing resin composition and the resin for molding material (C) to obtain a molding material. Molding material The method of manufacturing is also one of the present invention.
In the step of kneading the modified cellulose fiber-containing resin composition and the resin for molding material (C) to obtain a molding material, the kneading conditions such as the kneading temperature and the kneading time are usually the range in which the resin is kneaded. Can be set as appropriate.

Although it depends on the use of the molded product etc., from the viewpoint of the mechanical strength of the molded product, the modified cellulose fiber (A) is preferably contained in the final molding material to be a molded product, preferably 1 to 40% by mass, more preferably The content is 3 to 30% by mass, more preferably 5 to 25% by mass. Further, in order to sufficiently exhibit the mechanical strength of the molded product, the dispersing resin (B) is preferably contained in the molding material in an amount of 0.1 to 60% by mass, more preferably 1 to 40% by mass, still more preferably Is contained in an amount of 3 to 30% by mass, most preferably 5 to 25% by mass.
Thus, the content of the modified cellulose fiber-containing resin composition in the molding material is appropriately adjusted so that the contents of the modified cellulose fiber (A) in the molding material and the resin for dispersion (B) fall within the above range. Just do it.

The resin for molding material (C) is not particularly limited as long as it is a resin that can be molded and processed, and examples thereof include thermoplastic resins and thermosetting resins that are usually used for molding materials. For example, polylactic acid, aliphatic or aromatic polyester, vinyl chloride resin, vinyl acetate resin, polystyrene, ABS resin, acrylic resin, polyethylene, polyethylene terephthalate, polypropylene, fluorine resin, polyamide resin, acetal resin, polycarbonate, fibrous plastic, Polyesters such as polyglycolic acid, poly-3-hydroxybutyrate, poly-4-hydroxybutyrate, polyhydroxyvalerate polyethylene adipate, polycaprolactone, polypropiolactone, polyethers such as polyethylene glycol, polyglutamic acid, polylysine etc. Thermoplastic resins such as polyamide, polyvinyl alcohol, polyurethane, phenol resin, urea resin, melamine resin, unsaturated polyester resin, epoxy resin, Diallyl phthalate resins, polyurethane resins, silicon resins, etc. can be used thermosetting resins such as polyimide resins, it can be used in combination of at least one kind alone or two kinds, without limitation. In addition, biodegradable resins such as phenolic resins derived from biomass liquefied products, epoxy resins and urethane resins can also be used.
Among these, biodegradable resins, polyolefins such as polyethylene and polypropylene, polyamide resins, polycarbonates, phenol resins, epoxy resins, acrylic resins, acetal resins, aliphatic or aromatic polyesters are preferable, and polyolefins are more preferable. It is.

The modified cellulose fiber-containing resin composition and molding material of the present invention can be molded into various shapes and used. Examples of the shape include a sheet, a film, a pellet, and a powder. The molding material having these shapes can be obtained, for example, using press molding, injection molding, extrusion molding, blow molding, stretch molding, foam molding, transfer molding, lamination molding, cast molding, and the like.

If necessary, lubricants, waxes, colorants, stabilizers, fillers, and various other additives may be added to the molding material of the present invention described above.

Furthermore, from the above molding materials, molded articles are produced according to desired molding methods such as press molding, injection molding, extrusion molding, blow molding, stretch molding, foam molding, transfer molding, lamination molding, cast molding, and desired molding conditions. You can do it. Thus, a molded body produced from the molding material of the present invention is also one of the present invention.
Examples of the molded body include interior materials, exterior materials, structural materials, etc. of transportation equipment such as automobiles, trains, ships, airplanes, etc. Housings, electrical construction materials, such as personal computers, televisions, telephones, watches, etc., structural materials, internal parts Etc. Housings such as mobile communication devices such as mobile phones, structural materials, internal parts etc. Portable music reproducing devices, video reproducing devices, printing devices, copying devices, housings such as sporting goods, structural materials, internal components etc. Building materials Office equipment such as stationery, containers, containers, etc .;

Hereinafter, examples of the present invention will be described. The present invention is not limited to these examples.

The physical property value measurement methods used in some of these examples are as follows.
(1) Measurement of tensile strength (fracture), tensile elastic modulus (Young's modulus, elastic modulus) Based on JIS K-6732, it was measured with a tensile tester "Tensilon RTM-50" manufactured by Orientec Co., Ltd.
(2) Measurement of fiber dispersibility 0.2 g of a molding material and 100 g of xylene were placed in a separable flask, the internal temperature was set to 140 ° C., and the mixture was stirred for 3 hours. Thereafter, the precipitate was sampled, and the dispersion state of fibers was observed at a magnification of 1000 times using a CCD camera (VHX-600 manufactured by KEYENCE CORPORATION).
A case where the fiber having a width of 5 μm or more is 1 or less in 100 is ○, a fiber having a width of 10 μm or more is 1 or less in 100 and a fiber having a width of 5 μm or more is present in 2 or more Δ, the case where two or more fibers of 100 μm or more in width are present is represented by x.
(3) Confirmation of Denatured Reaction Progression The progress of the denatured reaction was observed using a Fourier Transform Infrared Spectrometer “Spectrum one” manufactured by Perkin Elmer. Specifically, it was confirmed qualitatively because the peak intensity derived from the stretching vibration of the carbonyl carbon and oxygen of the ester bond generated at 1650 to 1750 cm ⁻¹ is enhanced as the modification reaction proceeds.
(4) Measurement of Addition Rate of Acid Anhydride to Cellulose Fiber The addition rate was calculated from the mass change before and after modification of the cellulose fiber as shown in formula (I). The samples for which the addition rate was to be evaluated were washed with a sufficient amount of solvent and subjected to measurement. An acid anhydride good solvent was appropriately selected and used as the washing solvent.

Wp = (W-Ws) × 100 / Ws (I)

Wp: Addition rate of acid anhydride to cellulose fiber (% by mass)
W: dry mass of modified cellulose fiber (modified cellulose fiber) (g)
Ws: dry mass of cellulose fiber before modification (g)
(5) Measurement of solid content For measurement of solid content, an infrared moisture meter (manufactured by Ketto Scientific Research Institute: "FD-620") was used.

[Production of Modified Cellulose Fiber (A-1)]
250.00 g of softwood bleached kraft pulp containing water (hereinafter referred to as NBKP) (solid content of 50.00 g) and 200.00 g of N-methylpyrrolidone were placed in a container having a volume of 2000 ml, and water was distilled off to replace the solvent. I got NBKP. The system was adjusted to 70 ° C., 39.75 g of hexadecenylsuccinic anhydride as acid anhydride (a) and 8.53 g of potassium carbonate as an esterification catalyst were reacted for 2 hours. The reaction product was washed successively with ethanol, acetic acid and water, solvent-replaced with ethanol and then dried to obtain 79.81 g of modified cellulose fiber A-1. Ethanol was used as a washing solvent for the sample to evaluate the addition rate. The addition rate of the acid anhydride (a) to cellulose fiber in modified cellulose fiber A-1 was 59.6 mass%.

[Synthesis of acid anhydride group-containing petroleum resin (a-1)]
Petrotac 70 (Tosoh Corp. C5C9 petroleum resin: weight average molecular weight 1300, softening point 70 ° C., bromine number 45 Br ₂ g / 100 g) 1200.00 g is charged into a separable flask having a volume of 3000 ml, and the temperature is increased to 160 ° C. It was heated to a molten state. While maintaining the inside of the system at 160 ° C. and performing nitrogen substitution, 221.00 g of maleic anhydride and 6.00 g of t-butyl peroxide were added in 12 portions over 3 hours. After 2 hours from the end of the addition, the system is maintained at 180 ° C. after 2 hours under pressure reduction, and the purification operation is carried out by distilling off unreacted maleic anhydride by keeping for 2 hours while reducing pressure. The acid anhydride group-containing petroleum resin a-1 was obtained.

[Production of Modified Cellulose Fiber (A-2)]
In a container having a volume of 2000 ml, 250.00 g of NBKP (water content: 50 g) containing water and 200.00 g of N-methylpyrrolidone were charged, and water was distilled off to obtain solvent-substituted NBKP. The system was adjusted to 75 ° C., 50.00 g of acid anhydride group-containing petroleum resin a-1 was weighed as acid anhydride (a), and 8.53 g of potassium carbonate was added as an esterification catalyst and reacted for 3 hours . The reaction product was washed successively with tetrahydrofuran, acetic acid and water, solvent-replaced with ethanol and then dried to obtain 69.00 g of modified cellulose fiber A-2. Ethanol was used as a washing solvent for the sample to evaluate the addition rate. The addition ratio of the acid anhydride group-containing petroleum resin a-1 to the cellulose fiber in the modified cellulose fiber A-2 was 38% by mass.

[Production of comparative unmodified cellulose fiber (RA-1)]
1000 g (solid conversion 200 g) of NBKP was charged into a 5-liter flask, 3000 g of isopropanol was added, and the slurry obtained by mixing and stirring was separated by pressing solid-liquid separation. Thereafter, the same process was repeated five times on the pressed wet pulp to obtain an isopropanol wet pulp. Further, the solvent was heated under reduced pressure to obtain 204 g of a comparative unmodified cellulose fiber RA-1 (solid content 98%).

[Production of Comparative Modified Cellulose Fiber (RA-2)]
In a container having a volume of 2000 ml, 250.00 g (solid content 50.00 g) of water and 200.00 g of N-methylpyrrolidone were charged and water was distilled off to obtain solvent-substituted NBKP. The system was adjusted to 70 ° C., 17.33 g of acetic anhydride as an acid anhydride and 8.53 g of potassium carbonate as an esterification catalyst were added and reacted for 2 hours. The reaction product was washed successively with ethanol, acetic acid and water, solvent-replaced with ethanol and then dried to obtain 57.00 g of a comparative modified cellulose fiber RA-2. Ethanol was used as a washing solvent for the sample to evaluate the addition rate. The addition ratio of acetic anhydride to cellulose fibers in comparative modified cellulose fiber RA-2 was 14% by mass.

[Production of modified cellulose fiber (RA-3) for comparison]
In a container having a volume of 2000 ml, 250.00 g (solid content 50.00 g) of water and 200.00 g of N-methylpyrrolidone were charged and water was distilled off to obtain solvent-substituted NBKP. The system was adjusted to 70 ° C., 13.90 g of succinic anhydride as an acid anhydride and 8.53 g of potassium carbonate as an esterification catalyst were added and reacted for 2 hours. The reaction product was washed successively with ethanol, acetic acid and water, solvent-replaced with ethanol and then dried to obtain 63.67 g of modified cellulose fiber RA-3 for comparison. Ethanol was used as a washing solvent for the sample to evaluate the addition rate. The addition ratio of succinic anhydride to cellulose fibers in modified cellulose fiber RA-3 for comparison was 27% by mass.

[Production of comparative rosin ester resin (RB-1)]
Into a separable flask having a volume of 2000 ml, 1015.00 g of gum rosin, 90.00 g of glycerin and 1.00 g of magnesium acetate tetrahydrate were charged and reacted at 235 ° C. for 3 hours with stirring. The temperature in the system was raised to 280 ° C. and held for 22 hours, and then the pressure in the system was reduced, and then held for 5 hours to obtain a rosin ester resin RB-1 for comparison. The weight average molecular weight in terms of polystyrene measured by gel permeation chromatography was 920, and the softening point was 97 ° C.

[Production of Modified Cellulose Fiber-Containing Resin Composition]
Example 1
24.90 g of the modified cellulose fiber A-1 was weighed and used as a dispersing resin (B) in combination with 25.10 g of Quinton R100 (manufactured by Nippon Zeon Co., Ltd., C5 petroleum resin: weight average molecular weight 2250, softening point 96 ° C.) It charged into a plasto mill (made by Toyo Seiki Co., Ltd.) and melt-kneaded to obtain a modified cellulose fiber-containing resin composition C-1.

(Example 2) to (Example 8)
Modified cellulose fiber-containing resin composition C-2 to C in the same manner as in Example 1 except that the type of dispersing resin, the type of modified cellulose fiber, and the preparation ratio thereof are changed as shown in Table 1. -8 was obtained.

(Comparative example 1)
As a comparative example which does not use modified cellulose fiber (A), the resin composition which consists only of Quinton R100 was set as comparative modified cellulose fiber containing resin composition RC-1.

Comparative Example 2 to Comparative Example 3
As a comparative example which does not use the resin for dispersion (B), a resin composition consisting only of comparative unmodified cellulose fiber RA-1 is used as comparative modified cellulose fiber-containing resin composition RC-2, from only modified cellulose fiber A-1 The resulting resin composition is referred to as comparative modified cellulose fiber-containing resin composition RC-3.

(Comparative example 4)
19.2 g of a comparative unmodified cellulose fiber RA-1 was weighed and charged into a laboplast mill (made by Toyo Seiki Co., Ltd.) together with 30.8 g of Quinton R100 as a dispersing resin (B), and the mixture was melt-kneaded to make a comparative modification A cellulose fiber-containing resin composition RC-4 was obtained.

(Comparative Example 5) to (Comparative Example 6)
Comparative modified cellulose fiber-containing resin compositions RC-5 to RC-6 were obtained in the same manner as in Comparative Example 4 except that the type of the dispersing resin (B) was changed as shown in Table 1.

(Comparative Example 7) to (Comparative Example 8)
The modified cellulose fiber for comparison shown in Table 1 was used in place of the comparative unmodified cellulose fiber RA-1, and the preparation ratio of the modified cellulose fiber for comparison and the dispersing resin (B) was as shown in Table 1. Comparative modified cellulose fiber-containing resin compositions RC-7 to RC-8 were obtained in the same manner as Comparative Example 4 except for the above.

(Comparative Example 9) to (Comparative Example 13)
Instead of Quinton R100, the resin shown in Table 1 is used as a dispersing resin, and the same procedure as in Example 1 is carried out except that the preparation ratio of the modified cellulose fiber A-1 to the dispersing resin is as shown in Table 1. Thus, comparative modified cellulose fiber-containing resin compositions RC-9 to RC-13 were obtained.

(Comparative example 14)
As a comparative example which does not use resin (B) for dispersion | distribution, the resin composition which consists only of modified cellulose fiber A-2 was made into comparative modified cellulose fiber containing resin composition RC-14.

(Comparative example 15)
Comparative modified cellulose fiber-containing resin composition RC-15 was obtained in the same manner as Comparative Example 4 except that the preparation ratio of comparative unmodified cellulose fiber RA-1 and Quinton R100 was as shown in Table 1.

(* 1) Addition rate of acid anhydride to cellulose fiber (mass%)

The product names and abbreviations in Table 1 are as follows.
Quinton R100: Nippon Zeon Co., Ltd. C5 petroleum resin Weight average molecular weight 2250, softening point 96 ° C.
Petocol LX: Toso Co., Ltd. C9 petroleum resin Weight average molecular weight 1400 Softening point 98 ° C.
Coumarone G-90: manufactured by Nichibo Chemical Co., Ltd., coumarone resin weight average molecular weight 770, softening point 98 ° C.
YS Resin PX1000: Yashara Chemical Co., Ltd. Terpene resin Weight average molecular weight 880 Softening point 100 ° C
RB-1: Rosin ester resin for comparison Weight average molecular weight 920 Softening point 97 ° C
H1000P: Toyobo Co., Ltd. maleated polypropylene "Toyotack PMAH1000P" Softening point 140 ° C
Polystyrene: Wako Pure Chemical Industries, Ltd. Weight average molecular weight 208000 Softening point 140 ° C.
High density polyethylene: manufactured by Asahi Kasei Co., Ltd. Suntec-HD J320 Weight average molecular weight 56000 Softening point 96 ° C

[Production of molding material and molded article using high density polyethylene as resin for molding material]
(Example 9)
24.00 g of the modified cellulose fiber-containing resin composition C-1 obtained in Example 1 was weighed, and 26.00 g of high density polyethylene ("Suntech-HD J320" manufactured by Asahi Kasei Co., Ltd.) as a resin for molding material was used as a laboplast. The mixture was charged into a mill (manufactured by Toyo Seiki Co., Ltd.) and melt-kneaded to obtain a molding material. The obtained molding material is put into a manual injection molding machine (Imoto Machinery Co., Ltd .; model 18D1), injection molded at an injection temperature of 170 ° C., a mold temperature of 25 ° C., and a dumbbell-shaped test piece of 2 mm thickness (molding I got the body).

(Example 10) to (Example 11)
Each molded product was obtained in the same manner as in Example 9, except that the modified cellulose fiber-containing resin composition shown in Table 2 was used.
In each of the examples and the comparative examples, evaluation is performed by making the cellulose fiber content in the molding material the same.

(* 2) "Cellulose fiber fraction" in the example using modified cellulose fiber shows the cellulose fiber fraction in modified cellulose fiber, It represents with content (mass%) with respect to 100 mass% of molding materials. The same applies to the following tables.

(Comparative example 16)
12.05 g of the comparative modified cellulose fiber-containing resin composition RC-1 (Quinton R100) obtained in Comparative Example 1 was weighed, and high-density polyethylene "Suntech-HD J320" manufactured by Asahi Kasei Co., Ltd. as a resin for molding material The mixture was charged into a laboplast mill (manufactured by Toyo Seiki Co., Ltd.) together with 37.95 g of high density polyethylene (sometimes abbreviated as "high density polyethylene") and melt-kneaded to obtain a molding material. The obtained molding material is put into a manual injection molding machine (Imoto Machinery Co., Ltd .; model 18D1), injection molded at an injection temperature of 170 ° C., a mold temperature of 25 ° C., and a dumbbell-shaped test piece of 2 mm thickness (molding I got the body).

(Comparative Example 17) to (Comparative Example 28)
The same procedure as in Comparative Example 16 was performed except that the comparative modified cellulose fiber-containing resin composition shown in Table 3 was used and the compounding ratio shown in Table 3 was obtained, to obtain molded articles.

(Comparative example 29)
11.95 g of modified cellulose fiber A-1 was weighed, 12.05 g of Quinton R100 (C5 petroleum resin manufactured by Nippon Zeon Co., Ltd .: weight average molecular weight 2250, softening point 96 ° C.), 26.00 g of high density polyethylene and laboplast The mixture was collectively loaded into a mill (manufactured by Toyo Seiki Co., Ltd.), and was melted and kneaded to obtain a molding material. The obtained molding material was used, and the same operation as in Comparative Example 16 was performed to obtain a dumbbell-shaped test piece (a molded body).

(Reference Example 1)
An operation was carried out in the same manner as in Comparative Example 16 except that a material consisting only of high density polyethylene was used as a molding material, to obtain a molded body.

(* 3) Modified cellulose fiber, resin for dispersion, resin for molding material were charged at one time and melt-kneaded.

(Example 12)
26.60 g of the modified cellulose fiber-containing resin composition C-4 is weighed, and is put into a laboplast mill (made by Toyo Seiki Co., Ltd.) together with 23.40 g of high density polyethylene as a resin for molding material, and is melt-kneaded to form a molding material I got Using the obtained molding material, the same operation as in Example 9 was performed to obtain a dumbbell-shaped test piece (a molded body).

(Examples 13 to 16)
Each molded body was obtained by using the modified cellulose fiber-containing resin composition shown in Table 4 and performing the same operation as in Example 12 except that the compounding ratio shown in Table 4 was used.

(* 4) Ratio (% by mass) of modified cellulose fiber in 100% by mass of modified cellulose fiber-containing resin composition

[Production of molding material and molding using polypropylene as resin for molding material]
(Example 17)
24.00 g of the modified cellulose fiber-containing resin composition C-1 obtained in Example 1 was weighed, and polypropylene ("Prime Polypro J108M" manufactured by Prime Polymer Co., Ltd., hereinafter sometimes abbreviated as "polypropylene") 26. The mixture was charged into a laboplast mill (manufactured by Toyo Seiki Co., Ltd.) together with 00 g and melted and kneaded to obtain a molding material. The obtained molding material is put into a manual injection molding machine (Imoto Machinery Co., Ltd .; Model 18D1), injection molded at an injection temperature of 200 ° C., a mold temperature of 25 ° C., and a dumbbell-shaped test piece of 2 mm thickness I got the body).

(Comparative example 30)
7.5 g of the comparative modified cellulose fiber-containing resin composition RC-2 obtained in Comparative Example 2 was weighed, and 42.5 g of polypropylene ("Prime Polypro J108M" manufactured by Prime Polymer Co., Ltd.) as a resin for molding material was used as a laboplast mill The mixture was charged into (Toyoke Seiki Co., Ltd.) and melt-kneaded to obtain a molding material. The obtained molding material was used and the same operation as in Example 17 was performed to obtain a dumbbell-shaped test piece (a molded body).

Comparative Example 31 to Comparative Example 32
The same procedure as in Comparative Example 30 was performed except that the comparative modified cellulose fiber-containing resin composition shown in Table 5 was used and the compounding ratio shown in Table 5 was obtained, to obtain molded articles.

(Reference Example 2)
An operation was carried out in the same manner as in Example 17 except that a material consisting only of polypropylene was used as a molding material, to obtain a molded body.

[Production of molding material and molding using low density polyethylene as resin for molding material]
(Example 18)
12.50 g of the modified cellulose fiber-containing resin composition C-8 obtained in Example 8 was weighed, and low density polyethylene ("Novatec LC520" manufactured by Japan Polyethylene Corp., hereinafter "low density polyethylene") was used as a resin for molding material The mixture was charged into a laboplast mill (manufactured by Toyo Seiki Co., Ltd.) together with 37.50 g of the mixture, and the mixture was melt-kneaded to obtain a molding material. The obtained molding material is put into a manual injection molding machine (Imoto Machinery Co., Ltd .; Model 18D1), injection molded at an injection temperature of 200 ° C., a mold temperature of 25 ° C., and a dumbbell-shaped test piece of 2 mm thickness I got the body).

(Comparative example 33)
5.95 g of the comparative modified cellulose fiber-containing resin composition RC-14 obtained in Comparative Example 14 was weighed, and 46.55 g of low density polyethylene (Novatec LC520 manufactured by Nippon Polyethylene Corporation) as a resin for molding material was used as a laboplast. The mixture was charged into a mill (manufactured by Toyo Seiki Co., Ltd.) and melt-kneaded to obtain a molding material. Using the obtained molding material, the same operation as in Example 18 was performed to obtain a dumbbell-shaped test piece (a molded body).

(Comparative example 34)
A comparative modified cellulose fiber-containing resin composition shown in Table 6 was used, and the same operation as in Comparative Example 33 was performed except that the compounding ratio shown in Table 6 was obtained, to obtain a molded body.

(Reference Example 3)
An operation was carried out in the same manner as in Example 18 except that a material consisting only of low density polyethylene was used as a molding material, to obtain a molded body.

From the results of Example 9 and Comparative Example 16, it can be seen that excellent strength and elastic modulus can not be imparted to the molded product without using modified cellulose fiber.

From the results of Example 9 and Comparative Examples 17 to 18, it can be seen that the cellulose fiber can not be sufficiently miniaturized without containing the dispersing resin, and excellent strength and elastic modulus can not be imparted to the molded body.

From the results of Examples 10 to 11 and Comparative Examples 19 to 21, when the cellulose fiber is not modified with the cyclic polybasic acid anhydride, the cellulose fiber is sufficiently refined even using the dispersing resin in the present invention. It can be seen that it is impossible to impart excellent strength and elastic modulus to the molded product.

From the results of Example 9 and Comparative Examples 22 to 23, among the modified cellulose fibers, a modified cellulose fiber esterified by the addition of a cyclic polybasic acid anhydride having a hydrophobic group and having a carbon number of 15 or more was used. In some cases, by using the resin for dispersion in the present invention, the cellulose fiber can be sufficiently miniaturized, and the molded article exhibited excellent strength and elastic modulus.

From the results of Examples 9 to 11 and Comparative Examples 24 to 28, it is not possible to sufficiently refine the modified cellulose fiber in the present invention unless a petroleum resin or a coal resin is used as the dispersing resin, and a molded article is obtained. It can be seen that excellent strength and elastic modulus can not be imparted.

From the results of Example 9 and Comparative Example 29, if the modified cellulose fiber and the dispersing resin are kneaded in advance and then not kneaded with the molding material resin, the cellulose fiber can not be sufficiently miniaturized, and the molded article is excellent. It can be seen that the strength and modulus of elasticity can not be imparted.

From the results of Examples 12 to 16, when the ratio of modified cellulose fiber in the modified cellulose fiber-containing resin composition is included in the range of 20 to 70% by mass in 100% by mass of the modified cellulose fiber-containing resin composition, from that range In particular, the cellulose fiber can be made finer as compared with the case where it deviates, and the molded body exhibited excellent strength and elastic modulus.

From the results of Example 17 and Comparative Examples 30 to 32, even when the resin for molding material is changed from high density polyethylene to polypropylene, in the molded article containing the modified cellulose fiber-containing resin composition of the present invention, cellulose fibers are sufficient. It was miniaturized and showed excellent strength and elastic modulus.

From the results of Example 18 and Comparative Examples 33 to 34, even when the resin for molding material is changed from high density polyethylene to low density polyethylene, the molded article containing the modified cellulose fiber-containing resin composition of the present invention is a cellulose fiber It was sufficiently miniaturized and showed excellent strength and elastic modulus.

Claims (5)

Modified cellulose fiber comprising a modified cellulose fiber (A) esterified by addition of a cyclic polybasic acid anhydride (a) having a hydrophobic group and a carbon number of 15 or more to a cellulose fiber and a dispersing resin (B) It is a method of manufacturing a containing resin composition, Comprising: The following (i) and (ii) are satisfy | filled, The manufacturing method of the modified cellulose fiber containing resin composition characterized by the above-mentioned.
(I) the dispersion resin (B) is, the dispersion of at least a kind (ii) the modified cellulose fibers (A) selected from among petroleum resin and coal-based resin having a softening point of 40 ° C. or higher 135 ° C. or less Including the step of refining (A) by kneading with the resin (B) Content of the said modified cellulose fiber (A) is 20-70 mass% in 100 mass% of modified cellulose fiber containing resin compositions, The manufacturing method of the modified cellulose fiber containing resin composition of Claim 1 characterized by the above-mentioned. A molding comprising the step of kneading a modified cellulose fiber-containing resin composition obtained by the method for producing a modified cellulose fiber-containing resin composition according to claim 1 and a resin for molding material (C) to obtain a molding material Method of manufacturing material . The method for producing a molding material according to claim 3, wherein the resin (C) for a molding material is a polyolefin. Process for producing a molded article for producing a molded article from a molding material obtained by the production method of molding material according to claim 3 or 4.