JP6198005B2 - Method for producing cellulose fiber / resin composite composition, composite composition, resin composition for molding, and resin molded product - Google Patents

Description

  The present invention relates to a method for producing a cellulose fiber / resin composite composition, the composite composition, a molding resin composition, and a resin molded product.

  In recent years, the development of materials using biomass has become active due to growing resource and environmental problems. An attempt has been made to use cellulose as a resin reinforcing agent by taking advantage of its high elastic modulus, high strength, and light weight (Patent Document 1). In particular, it has been noticed that an excellent reinforcing effect is exhibited by refining an aggregate of cellulose fibers to the nano level and increasing the specific surface area. However, since cellulose fibers have many hydroxyl groups, they are highly hydrophilic and generally poorly compatible with hydrophobic resins. Therefore, it is difficult to obtain a composite that is uniformly dispersed in the resin, and sufficient mechanical strength cannot be exhibited. In addition, when a cellulose fiber is used as a filler, it is generally added in a dry state when it is combined with a resin. Particularly, highly fibrillated cellulose fibers are likely to aggregate during drying, and this is used as a filler. There is a problem that aggregates remain in the composite when combined with the resin.

  For the purpose of improving the dispersibility in complexing cellulose with a resin, a cellulose modification technique has been studied. For example, Patent Document 2 discloses a method in which microfibril cellulose is surface-modified and dispersed in an organic solvent. Patent Document 3 discloses a method in which microfibril cellulose is reacted with a carboxylic acid anhydride such as acetic anhydride to esterify 25% or more of the hydroxyl groups present on the surface of microfibrillated cellulose. Methods for modifying fibril cellulose with alkyl succinic anhydride or alkenyl succinic anhydride are disclosed respectively.

  Furthermore, as an example of using cellulose fibers that are not modified as described above, in Patent Document 5, in order to suppress the aggregation of microfibril cellulose, the microfibril cellulose is freeze-dried under vacuum and then melted at a high temperature. A method of combining with a thermoplastic resin is disclosed. However, the freeze-drying method has poor productivity and is not suitable for processing on a large scale.

  In Non-Patent Document 1, after freeze-drying cellulose nanofibers mixed with a surfactant in water, a toluene solution of polypropylene is added to a suspension dispersed in toluene, and the toluene is volatilized. A technique for producing a composite material by melt-kneading with a biaxial kneader has been disclosed, and the cellulose nanofibers subjected to the treatment showed good dispersibility in toluene, but by adding a surfactant It is described that the strength reinforcing effect of the composite material was not observed.

JP 2008-266630 A JP-T-2002-524618 Japanese National Patent Publication No. 11-513425 JP 2012-324563 A JP 2009-107156 A

Shinichiro Iwamoto Examination of cellulose nanofiber dispersion method of cellulose and rig in polypropylene composite material, Cellulose Commun. (Vol. 21, No. 1, 2014), 21-24

  The present invention provides a method for producing a cellulose fiber / resin composite composition that can satisfactorily disperse a highly hydrophilic cellulosic material in a hydrophobic resin such as a polyolefin resin, and is obtained by the production method. It aims at providing the resin molding excellent in the mechanical strength containing the cellulose fiber / resin composite composition obtained.

  The inventor suppresses the formation of cellulose aggregates by suppressing hydrogen bonding between celluloses when drying the cellulose compounded with the hydrophobic thermoplastic resin, and the resin is dispersed in a solvent by the resin. With the idea of being able to cover it, we conducted an extensive study. As a result, polyolefin resin was used as a coating material for cellulose, and after heating so that cellulose and the resin could be uniformly mixed in a specific solvent, cooling was performed, the knowledge that the resin was deposited on the cellulose surface was obtained. It was.

  The present invention has been completed based on this finding and further earnest studies. That is, after adding the polyolefin resin (B) to the suspension in which the cellulose fibers (A) are dispersed in the hydrophobic organic solvent (C), the cellulose fibers (A) are uniformly dispersed and the polyolefin resin (B). A cellulose fiber / resin composite composition characterized by heating to a dissolved state and cooling the system to precipitate a content containing a polyolefin resin (B); obtained by the production method The present invention relates to a cellulose fiber / resin composite composition; a molding resin composition comprising the composite composition; and a resin molded product obtained from the composite composition or the molding resin composition.

  According to the present invention, the polyolefin resin (B) is easily dissolved between the fibrils of the cellulose fiber (A) by heating and dissolving the polyolefin resin (B) in the hydrophobic organic solvent (C). Become. By cooling and precipitating the polyolefin resin (B) in this state, a cellulose fiber / resin composite composition in which aggregation between celluloses is suppressed even when dried is obtained. Therefore, in the molded product containing the cellulose fiber / resin composite composition of the present invention, the cellulose fibers (A) are uniformly dispersed in the resin, and can exhibit excellent mechanical strength. Moreover, according to this invention, since it can process at low temperature rather than melting | fusing point of polyolefin resin (B), coloring and decomposition | disassembly of a cellulose fiber (A) can be suppressed. In the present invention, the desired cellulose / resin composite composition can be obtained without the addition of a freeze-drying treatment or a surfactant described in the prior art document.

  Hereinafter, a method for producing a cellulose fiber / resin composite composition of the present invention, a cellulose fiber / resin composite composition obtained by the production method, a molding resin composition comprising the composite composition, and a resin molded product explain.

(Cellulose fiber)
It does not specifically limit as a cellulose fiber (A) (henceforth a component (A)) used for this invention, Various well-known things can be used. Specifically, from fibers derived from plant fibers such as plant-derived pulp, wood, cotton, hemp, bamboo, kenaf, hemp, seaweed, fibers separated from animal fibers produced by sea squirts, or acetic acid bacteria Examples include bacterial cellulose produced and cellulose obtained from waste paper. Among these, fibers separated from plant fibers are preferable, and pulp or cotton is more preferable.

(Form of cellulose fiber)
As the component (A), fine cellulose may be used. As long as the component (A) retains the fiber form, there is no particular limitation on the miniaturization method. A method of making the component (A) fine by mechanical action, a method of performing mechanical treatment after chemical treatment such as TEMPO oxidation, ozone oxidation, enzyme treatment, and the like can be used.

  The component (A) obtained by the above treatment preferably has an average fiber diameter of 1.0 μm or less, and more preferably 0.3 μm or less. Examples of commercially available products include “Serisch KY100G” (manufactured by Daicel Corporation) and “Binfisu WMa-10005” (manufactured by Sugino Machine Co., Ltd.). When the component (A) having a particle size of 1.0 μm or less is used, it is easy to obtain a molding material exhibiting good mechanical strength.

  As the component (A) to be used, a part of the hydroxyl group previously esterified with a known esterifying agent may be used. In addition, in this esterification reaction, you may make the component (A) react the fiber which gave said refinement | miniaturization process, and an esterifying agent. Examples of the esterifying agent include carboxylic acids, acid anhydrides and acid halides. Specific examples include aliphatic carboxylic acids such as acetic acid, propionic acid, butyric acid, acrylic acid and methacrylic acid; benzoic acid and naphthalenecarboxylic acids. And aromatic carboxylic acids such as rosin compounds; and derivatives thereof. Among these, it is preferable to use acetic anhydride from the viewpoint of low cost and availability, and to use an acid anhydride of a rosin compound from the viewpoint of increasing the mechanical strength of the final molding material.

  The rosin compound is obtained by polymerizing natural rosin such as gum rosin, wood rosin, tall oil rosin, distilled rosin obtained by distilling natural rosin, hydrogenated rosin obtained by hydrogenating natural rosin, and natural rosin. Examples thereof include polymerized rosin, disproportionated rosin obtained by disproportionating natural rosin, and unsaturated carboxylic acid-modified rosin obtained by modifying natural rosin with unsaturated carboxylic acid. Examples of the unsaturated carboxylic acid-modified rosin include maleated rosin, fumarized rosin, and acrylated rosin. As the rosin compound, a rosin compound obtained by combining two or more operations such as distillation, hydrogenation, polymerization, disproportionation, and unsaturated carboxylic acid modification can also be used. These rosin compounds may be used alone or in a combination of two or more.

  The method for producing the acid anhydride of the rosin compound is not particularly limited, and various known methods can be employed. A method of dehydrating and condensing the rosin compound using a dehydrating agent, or a lower method such as acetic anhydride. A method of reacting the rosin compound in a carboxylic acid anhydride is well known.

(Esterification of cellulose)
The method of reacting the esterifying agent with the hydroxyl group of the cellulose fiber while suppressing the decomposition of the cellulose fiber is not particularly limited, and a known method can be adopted. The esterification is performed, for example, by reacting a slurry liquid composed of component (A), an esterifying agent and an organic solvent that does not react with the above components in a predetermined reaction vessel at 25 to 200 ° C., preferably 50 to 190 ° C. You can do it. The organic solvent is preferably one that can be sufficiently removed after the reaction. Usable organic solvents include, for example, saturated aliphatic solvents such as hexane and heptane, aromatic solvents such as toluene, xylene and pyridine, ketone solvents such as acetone and methyl ethyl ketone, and ether solvents such as tetrahydrofuran and diethyl ether. Examples thereof include a solvent, a sulfone solvent such as dimethyl sulfoxide, and an amide solvent such as dimethylformamide.

  Examples of the component (B) to be combined with the component (A) include polypropylene resins such as polypropylene, low density polyethylene, high density polyethylene, ultra low density polyethylene, and linear low density polyethylene, polypropylene, poly-1-butene, In addition to polyisobutylene and polypentene, ethylene-based copolymers such as ethylene-vinyl acetate copolymer, ethylene-methyl methacrylate copolymer, ethylene-ethyl acrylate copolymer, etc. are mentioned. And from the surface of a price, it is preferable to use a polypropylene and a polyethylene resin.

  In the production method of the present invention, after adding the component (B) to the suspension in which the component (A) is dispersed in the component (C), the uniform dispersion of the component (A) is maintained and the component (B) ), And the contents containing the component (B) are precipitated while cooling the system.

  In addition, since a component (A) is a water-containing state normally and a component (A) will aggregate in a hydrophobic organic solvent, it needs to substitute by an organic solvent previously. The substitution method is not particularly limited, but it is preferable to replace the hydrophobic organic solvent immiscible with water after removing water in the component (A). For example, the “two-stage substitution method” is effective. . In the two-stage substitution method, first, a hydrophilic organic solvent such as acetone, methyl ethyl ketone, isopropyl alcohol, tetrahydrofuran, N-methyl-2-pyrrolidone is added to the water-containing component (A) and dispersed, followed by suction filtration. Then, the water and the organic solvent in the component (A) are removed. The number of operations is not particularly limited, and the operation may be performed a plurality of times so as to obtain a desired moisture removal rate. Next, a hydrophobic organic solvent such as cyclohexane, toluene or xylene is added and dispersed, and then suction filtration is performed to replace the hydrophobic organic solvent. The number of operations is not particularly limited, and may be performed a plurality of times. Furthermore, as another method, a method of adding a hydrophilic organic solvent and a hydrophobic organic solvent in combination and performing azeotropic dehydration can also be mentioned.

  Examples of the component (C) include methyl acetate, ethyl acetate, methylene chloride, chloroform, toluene, xylene, n-hexane, cyclohexane and the like. Among these, from the viewpoint of work safety, it is preferable to use a solvent having a relatively high boiling point, and toluene and xylene are more preferable. In addition, you may use the same thing as the hydrophobic organic solvent used by the organic solvent substitution of the said component (A) for a component (C).

  In the production method according to the present invention, for example, the component (A) and the component (C) that have been substituted with an organic solvent in advance are charged into a reactor equipped with a cooling pipe and a thermometer. The amount of component (C) charged can be appropriately determined so that component (A) is a suspension having a concentration of 0.1 to 5% by weight. Next, component (B) is added while stirring the suspension at about 200 to 300 rpm. The component (B) may be added as a solid (powder, pellet, etc.), may be added dispersed in the component (C), and the amount of component (B) added If there is a large amount, component (C) may be added as appropriate in order to adjust the concentration in the system. In any of the above cases, the solid content concentration in the system containing the components (A), (B) and (C) is usually 0.1 to 85% by weight, preferably 1 to 50% by weight. What is necessary is just to adjust the usage-amount of an ingredient. After stirring for a period of about 1 to 120 minutes at a predetermined heating temperature such that component (A) is uniformly dispersed and component (B) is in a dissolved state, the suspension is cooled to 20 to 60 ° C. or less, and component ( Precipitate the contents containing B). After the precipitate and component (C) are separated by filtration or decantation, the cellulose fiber / resin composite composition can be obtained by drying the precipitate under reduced pressure or air drying. The “contents containing component (B)” is preferably a component (A) coated with component (B), but partially contains a precipitate consisting only of component (B). Or a small amount of component (C) may be contained. Moreover, you may process the manufacturing method concerning this invention under the pressurization of 0.1-5.0 MPa as needed.

  The usage ratio of the component (A) and the component (B) used in the production method can be arbitrarily determined according to the usage mode of the obtained cellulose fiber / resin composite composition, and cannot be uniquely determined. That is, when the content of the component (A) in the composite composition is relatively large, the composite composition can be directly kneaded into a desired matrix resin, and the content of the component (B) in the composite composition When the amount is relatively large, the composite composition can be applied as a master batch as it is, and further determined as appropriate according to the usage mode such as being able to be used as a molding material as it is. Solid content ratio [(A) / (B)] = 99.9 / 0.1 to 0.1 / 99.9, more preferably 1/99 to 99/1, particularly preferably 5/95 to 95 / 5. If it is less than 0.1 / 99.9, sufficient strength effect cannot be obtained, and if it is 99.9 / 0.1 or more, the dispersibility tends to decrease.

  The heating temperature in the system depends on the type of the component (B) and cannot be determined uniquely. However, the coloring / decomposition of the component (A) and the component (B) with respect to the component (C) are not necessarily determined. From the viewpoint of solubility, it is usually preferable that the temperature is about 80 to 200 ° C.

(Preparation of molding resin composition)
Regarding the cellulose fiber / resin composite composition produced according to the present invention, when the content of the component (B) is relatively high, it can be used as it is as a molding material such as injection molding, extrusion molding or transfer molding. In addition, a molding resin composition blended with a matrix resin can be prepared by using the composition as a master batch. As the matrix resin used for the preparation of the molding resin composition, it is better to use the same resin as the component (B) used for the preparation of the composite composition, thereby improving the mechanical strength and homogeneity of the resulting molding. This is preferable.

  When the composition is used as a master batch and blended into a matrix resin, a known melt-kneading method can be used. Specific examples include a twin screw extruder, a Henschel mixer, a Banbury mixer, a single screw extruder, a multi-screw extruder, and a kneader.

  In addition, in the resin composition for shaping | molding of this invention, arbitrary additives can also be mix | blended according to various objectives within the range which does not impair the effect of this invention remarkably. Additives include inorganic fillers, pigments such as iron oxides; lubricants and mold release agents such as stearic acid, behenic acid, zinc stearate, calcium stearate, magnesium stearate, ethylene bisstearamide; paraffin-based process Softeners and plasticizers such as oils, naphthenic process oils, aromatic process oils, paraffins, organic polysiloxanes and mineral oils; antioxidants such as hindered phenolic antioxidants and phosphorus thermal stabilizers; hindered amines Examples thereof include light stabilizers, benzotriazole-based ultraviolet absorbers; antistatic agents; reinforcing agents such as organic fibers, glass fibers, carbon fibers, and metal whiskers; colorants, other additives, and mixtures thereof.

(Preparation of resin molding)
The resin molded product of the present invention can be obtained by molding the molding resin composition by a known molding method. The molding conditions cannot be uniquely defined, but the temperature and pressure may be appropriately adjusted in consideration of the deformation and coloring of the target molded product. Specific examples of the molding method include injection molding, extrusion molding, transfer molding, blow molding, hot press molding, calendar molding, coating molding, cast molding, dipping molding, vacuum molding, transfer molding, and the like.

  The resin molded product obtained by the above method can be developed for applications such as electronic / electrical equipment, home appliances, containers, and automobile interior materials. More specifically, there are applications such as housings for home appliances, electronic / electrical devices, wrapping films, storage cases such as CD-ROMs and DVDs, tableware, food trays, beverage bottles, and chemical wrap materials.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated further in detail, this invention is not limited to these.

(Substitution degree of cellulose)
The degree of substitution of cellulose is determined from the degree to which three hydroxyl groups in anhydrous glucose, which is a repeating unit of cellulose, are ester-bonded to rosin or acetic acid (hereinafter referred to as DS). DS was calculated by pyrolysis GC / MS analysis. The measurement was performed after adding tetramethylammonium hydroxide and allowing to stand for 15 minutes, and then using the following apparatus at a thermal decomposition temperature of 450 ° C.
(Pyrolysis GC / MS analyzer:
Thermal decomposition apparatus: PY-2020D (manufactured by FRONTIER LAB)
GC / MS: HP6890 / 5973 (manufactured by Agilent Technologies)
Column: UA-5 (manufactured by FRONTIER LAB)
DS is calculated | required using Formula 1 from content of the rosin compound quantified by pyrolysis GC / MS analysis.

(Formula 1) DS = (A / M) / {(100-A) / 162}
(A: content of rosin compound determined (% by weight), M: molecular weight of rosin (299) or molecular weight of acetic acid (60), 162: molecular weight of glucose)

Example 1
<Solvent substitution of cellulose dispersion>
Work of adding 2000 g of acetone to 200 g (solid content 20 g + water 180 g), stirring and filtering fine cellulose (1) (“Cerish KY100G” manufactured by Daicel Corporation, average fiber diameter 0.3 μm, solid content concentration 10%) Repeated twice. Subsequently, 2000 g of xylene was added, and the operation of stirring and filtering was repeated three times. Then, xylene was added again so that the cellulose concentration became 1% to obtain a fine cellulose (1) / xylene dispersion.

<Coating of cellulose with resin>
1800 g of fine cellulose (1) / xylene dispersion obtained above (1 g) (solid content 18 g) was placed in a Kolben equipped with a cooling tube and stirred at 300 rpm with polypropylene ("Novatec" manufactured by Nippon Polypro Co., Ltd.). PP-BC2E ") 0.95 g was added. This suspension was heated to 120 ° C., and polypropylene was dissolved in xylene. After incubating at 120 ° C. for 10 minutes, the suspension was rapidly cooled to 30 ° C. or lower to precipitate a polypropylene-derived component. After cooling, the suspension was filtered, and the precipitate was dried under reduced pressure to obtain a master batch 1 (containing 5% resin) having a dry weight of 18.7 g (yield 98.7%).

Example 2
Resin coating treatment was performed in the same procedure as in Example 1 except that the amount of the polypropylene was 7.71 g, to obtain a master batch 2 (containing 30% resin). The dry weight was 24.4 g (yield 95.0%).

Example 3
Resin coating treatment was performed in the same procedure as in Example 1 except that the amount of the polypropylene was changed to 42.0 g to obtain a master batch 3 (containing 70% resin). The dry weight was 57.8 g (yield 96.4%).

Example 4
Resin coating treatment was performed in the same procedure as in Example 1 except that the amount of polypropylene was changed to 342.0 g to obtain a master batch 4 (containing 95% resin). The dry weight was 346.1 g (yield 96.1%).

Example 5
Resin coating treatment was performed in the same procedure as in Example 1 except that the amount of polypropylene was changed to 0.02 g to obtain a master batch 5 (containing 0.1% resin). The dry weight was 17.8 g (yield 98.6%).

Example 6
<Solvent substitution of cellulose dispersion>
The operation of adding 2000 g of acetone to 200 g of the fine cellulose (1) (solid content 20 g + water 180 g) and stirring and filtering was repeated twice. Subsequently, 2000 g of xylene was added, and the operation of stirring and filtering was repeated three times. Then, xylene was added again so that the cellulose concentration became 1% to obtain a fine cellulose (1) / xylene dispersion.

<Modification of cellulose with rosin acid anhydride>
The 1% fine cellulose (1) / xylene dispersion 1900 g (solid content 19 g) obtained above was placed in a Kolben equipped with a cooling tube, and rosin acid anhydride (Arakawa Chemical Co., Ltd.) synthesized by a conventional method while stirring at 300 rpm. 216 g (manufactured by Kogyo Co., Ltd.) was added, and the temperature was raised to 140 ° C. and reacted for 3 hours. After the reaction, the mixture was filtered and the residual rosin content was removed by washing with xylene five times, and then xylene was added again to obtain a cellulose concentration of 1% to obtain a rosin-modified finely divided cellulose / xylene dispersion. The obtained rosin-modified fine cellulose had a DS of 0.14.

<Coating of cellulose with resin>
1800 g of the rosin-modified fine cellulose / xylene dispersion (18 g in terms of cellulose solid content) was placed in a Kolben equipped with a cooling tube, and polypropylene (“Novatech PP-BC2E” manufactured by Nippon Polypro Co., Ltd.) was stirred while stirring at 300 rpm. 7.71 g was added. This suspension was heated to 120 ° C., and polypropylene was dissolved in xylene. After incubating at 120 ° C. for 10 minutes, the suspension was rapidly cooled to 30 ° C. or lower to precipitate a polypropylene-derived component. After cooling, the suspension was filtered, and the precipitate was dried under reduced pressure to obtain a master batch 6 (containing 30% resin) having a dry weight of 30.9 g (yield 96.0%).

Example 7
Except that the amount of polypropylene was changed to 42.0 g, a resin coating treatment was performed in the same procedure as in Example 6 to obtain a master batch 7 (containing 70% resin). The dry weight was 72.2 g (yield 96.2%).

Example 8
Acetyl-modified fine cellulose was obtained in the same procedure as in Example 6 except that 10 g of acetic anhydride was added instead of rosin acid anhydride. The acetyl-modified fine cellulose obtained had a DS of 0.14. Resin coating treatment on acetyl-modified fine cellulose was performed in the same procedure as in Example 6 to obtain a master batch 8 (containing 30% resin). The dry weight was 25.7 g (yield 96.5%).

Example 9
Resin coating treatment was performed in the same procedure as in Example 1 except that the polypropylene was changed to a polyethylene resin (“Novatech US8909” manufactured by Nippon Polyethylene Co., Ltd.) to obtain a master batch 9 (containing 5% resin). The dry weight was 18.4 g (yield 97.1%).

Example 10
Resin coating treatment was performed in the same procedure as in Example 2 except that the polypropylene was changed to a polyethylene resin (“Novatech US8909” manufactured by Nippon Polyethylene Co., Ltd.) to obtain a master batch 10 (containing 30% resin). The dry weight was 24.8 g (yield 96.4%).

Example 11
Resin coating treatment was performed in the same procedure as in Example 3 except that the polypropylene was changed to a polyethylene resin (“Novatech US8909” manufactured by Nippon Polyethylene Co., Ltd.) to obtain a master batch 11 (containing 70% resin). The dry weight was 56.9 g (yield 94.9%).

Example 12
Resin coating treatment was performed in the same procedure as in Example 1 except that it was changed to fine cellulose (2) (“Binfisu WMa-10005” manufactured by Sugino Machine Co., Ltd., average fiber diameter: 0.02 μm). (5% resin) was obtained. The dry weight was 17.6 g (yield 93.1%).

Example 13
Except having changed into the said fine cellulose (2), the resin coating process was performed in the procedure similar to Example 2, and the masterbatch 13 (30% of resin containing) was obtained. The dry weight was 24.6 g (yield 95.7%).

Example 14
Except having changed to the said fine cellulose (2), the resin coating process was performed in the procedure similar to Example 3, and the masterbatch 14 (70% resin containing) was obtained. The dry weight was 56.0 g (yield 93.3%).

Example 15
Except having changed to hardwood bleached kraft pulp (LBKP, average fiber diameter of 20 μm), resin coating treatment was performed in the same procedure as in Example 1 to obtain a master batch 15 (containing 5% resin). The dry weight was 18.4 g (yield 96.9%).

Example 16
Except having changed into the said hardwood bleached kraft pulp, the resin coating process was performed in the procedure similar to Example 2, and the masterbatch 16 (resin 30% containing) was obtained. The dry weight was 24.7 g (yield 95.9%).

Example 17
Except having changed into the said hardwood bleached kraft pulp, the resin coating process was performed in the procedure similar to Example 3, and the masterbatch 17 (resin 70% containing) was obtained. The dry weight was 56.4 g (yield 94.0%).

Comparative Example 1
A master batch 18 (containing 0% resin) was obtained in the same manner as in Example 1 except that the polypropylene was not added. The dry weight was 17.8 g (yield 98.9%).

Comparative Example 2
A master batch 19 (containing 0% resin) was obtained in the same manner as in Example 12 except that the polypropylene was not added. The dry weight was 17.5 g (97.3%).

Comparative Example 3
A master batch 20 (containing 0% resin) was obtained in the same manner as in Example 15 except that the polypropylene was not added. The dry weight was 17.8 g (98.8%).

* Ro treatment: Component modified with rosin acid anhydride (A)
Ac treatment: component modified with acetic anhydride (A)
PP: Polypropylene ("Novatec PP-BC2E" manufactured by Nippon Polypro Co., Ltd.)
PE: Polyethylene resin ("Novatec US8909" manufactured by Nippon Polyethylene Co., Ltd.)

(Method for creating a dispersion evaluation sheet)
The masterbatch and matrix resin produced in Examples 1 to 17 and Comparative Examples 1 to 3 were kneaded at 200 ° C. for 5 minutes in a kneader (DMS, small kneader Xplore MC15M) to prepare pellets. In addition, the masterbatch and matrix resin were mixed by the kind and compounding quantity (part by weight) which are shown in Tables 2-5 so that all the cellulose fiber ratios in a final molded product might be 5 weight%.
1 g of the obtained pellets were heated and pressed at 200 ° C. and 5 MPa for 1 minute, and then cooled to prepare dispersibility evaluation sheets (Evaluation Examples 1 to 17 and Comparative Evaluation Examples 1 to 4).

(Dispersibility evaluation)
By visual observation of the dispersibility evaluation sheet, the number of cellulose aggregates (particles having a width exceeding 500 μm) in the sheet was measured. In addition, about the evaluation result, it showed in Table 2-Table 5 for every kind of masterbatch and matrix resin.

(Strength evaluation method)
The cellulose fiber / resin master batch and matrix resin produced in Examples 1 to 17 and Comparative Examples 1 to 3 were mixed so that the cellulose fiber ratio in the final molded product was all 5% by weight, and in the kneader The mixture was kneaded at 200 ° C. for 5 minutes, and a dumbbell-type small test piece (JIS K7161 1BA type) was produced at a mold temperature of 40 ° C. and a pressure of 0.1 MPa using an injection molding machine (compact injection molding machine Xplore IM12M manufactured by DMS). . The tensile strength was measured according to JIS K7161. The evaluation results are shown in Tables 2 to 5 separately as described above.

* Masterbatch: Serisch KY100G / PP, Matrix resin: PP

  As shown in Table 2, compared with Comparative Evaluation Example 1, the sheets obtained in Evaluation Examples 1 to 8 showed good dispersibility and were excellent in a composition molded using a matrix resin. It was found that it showed the desired strength.

* Masterbatch: Serisch KY100G / PE, Matrix resin: PE

  As shown in Table 3, compared with Comparative Evaluation Example 4, the sheets obtained in Evaluation Examples 9 to 11 showed good dispersibility and were excellent in a composition molded using a matrix resin. It was found that it showed the desired strength.

* Masterbatch: Binfisu WMa / PP, Matrix resin: PP

  As shown in Table 4, compared with Comparative Evaluation Example 2, the sheets obtained in Evaluation Examples 12 to 14 showed good dispersibility and were excellent in a composition molded using a matrix resin. It was found that it showed the desired strength.

* Masterbatch: LBKP / PP, Matrix resin: PP

As shown in Table 5, compared with Comparative Evaluation Example 3, the sheets obtained in Evaluation Examples 15 to 17 showed good dispersibility and were excellent in a composition molded using a matrix resin. It was found that it showed the desired strength.

Claims (7)

After adding the polyolefin resin (B) to the suspension in which the cellulose fiber (A) is dispersed in the hydrophobic organic solvent (C), the cellulose fiber (A) is uniformly dispersed and the polyolefin resin (B) is dissolved. A method for producing a cellulose fiber / resin composite composition, characterized by heating to a state and cooling the system to precipitate a content containing a polyolefin resin (B). The production method according to claim 1, wherein the cellulose fiber (A) is a fine cellulose having an average fiber diameter of 1.0 µm or less, a cellulose fiber (A), or an acid anhydride modified product of the fine cellulose . The manufacturing method according to claim 2, wherein the acid anhydride-modified product of the cellulose fiber (A) is esterified with acetic anhydride or an acid anhydride of a rosin compound. The solid content ratio ((A) / (B)) of the cellulose fiber (A) and the polyolefin resin (B) used for the production is 1/99 to 99/1. Method. A cellulose fiber / resin composite composition produced by the method according to claim 1 , wherein the cellulose fiber (A) is an acid anhydride-modified product. Composition. A molding resin composition obtained by blending the cellulose fiber / resin composite composition according to claim 5. A resin molded product obtained from the cellulose fiber / resin composite composition or the molding resin composition according to claim 5.