JP2021036054A5 - - Google Patents

Description

Fibrous cellulose and its manufacturing method, and fibrous cellulose composite resin and its manufacturing method

The present invention relates to a fibrous cellulose and a method for producing the same, and a fibrous cellulose composite resin and a method for producing the same.

In recent years, nanotechnology has been attracting attention for the purpose of refining substances to the nanometer level and obtaining new physical properties different from the conventional properties of substances. Cellulose fine fibers (cellulose nanofibers) produced from pulp, which is a cellulosic raw material, by chemical treatment, crushing, etc. are excellent in strength, elasticity, thermal stability, etc., so they are filter media, filter aids, and ion exchange. Used for industrial applications such as body substrates, fillers for chromatographic analysis equipment, fillers for blending resins and rubbers, and blending cosmetics such as lipsticks, powder cosmetics, and emulsified cosmetics. Is expected. In addition, since cellulose nanofibers have excellent water-based dispersibility, they are viscosity-retaining agents for foods, cosmetics, paints, etc., fortifiers for food raw material fabrics, water-retaining agents, food stabilizers, low-calorie additives, and emulsification. It is expected to be used in many applications such as stabilizing aids. At present, it has been proposed to use cellulose nanofibers as a reinforcing material for resin.

However, when cellulose nanofibers are used as a reinforcing material for the resin, the cellulose nanofibers irreversibly aggregate due to intermolecular hydrogen bonds derived from the hydroxyl groups of the polysaccharide. Therefore, even if the cellulose nanofibers are used as the reinforcing material, there is a problem that the reinforcing effect of the resin is not sufficiently exhibited due to the poor dispersibility of the cellulose nanofibers in the resin.

Therefore, for example, Patent Document 1 is a method for producing a resin composition, which comprises compounding a thermoplastic resin, a plant fiber composition, and a plant fiber modifier while melting and kneading the plant. We propose a method for producing a plant fiber-containing resin composition, which comprises the conditions that the plant fibers in the fiber composition satisfy the conditions of an average fiber length of 0.1 to 0.7 mm and an average fiber width of 2 to 15,000 nm.

However, according to the findings of the present inventors, the strength of the resin is not sufficient simply by specifying the average fiber length and the average fiber width. Further, setting the average fiber width to 2 to 15,000 nm is substantially synonymous with the fact that the fiber is defibrated because the range is too wide, and development cannot proceed on the premise of this proposal.

Japanese Unexamined Patent Publication No. 2014-193959

A main problem to be solved by the present invention is to provide a fibrous cellulose having a large resin reinforcing effect and a method for producing the same, and a fibrous cellulose composite resin having high strength and a method for producing the same.

In order to solve the above problems, the present inventors have applied various treatments to cellulose nanofibers (cellulose fine fibers), and have searched for a kneading method of cellulose nanofibers and a resin. In other words, various studies were conducted on the premise of using cellulose nanofibers. However, when the cellulose nanofibers are composited with the resin, even if hydrophobic modification is performed or a compatibilizer is used, the dispersibility in the resin is not sufficient, and a sufficient three-dimensional network can be formed in the resin. It was difficult and a sufficient reinforcing effect could not be obtained. However, in the process of the research, it is possible that the raw material fiber is microfiber cellulose, which has better dispersibility in the resin than the cellulose nanofiber, and a sufficient three-dimensional network is formed in the resin. It was found that it was possible and a good reinforcing effect could be obtained, and it was found that it was preferable in solving the above-mentioned problems, and the present invention was conceived.

In this regard, Patent Document 1 proposes that the average fiber width of plant fibers is 2 to 15,000 nm, but this proposal has an extremely wide range and includes cellulose nanofibers. Therefore, it has not been easy to conceive of selecting microfiber cellulose as a raw material fiber under the flow of the conventional technique of defibrating, that is, thinning the fiber. Nevertheless, the present inventors came up with this idea and finally came up with the invention. The following are means for solving the above problems.
(Means according to claim 1)
The raw material fibers are defibrated to obtain fibrous cellulose having an average fiber width of 0.1 to 15 μm.
This fibrous cellulose, resin, and polybasic acid are kneaded and treated.
During the kneading treatment, the fibrous cellulose was modified with the polybasic acid to obtain the same.
Prior to the kneading, dehydration treatment and drying treatment are performed so that the water content of the fibrous cellulose is 5% or less.
A method for producing a fibrous cellulose composite resin.
(Means according to claim 2)
The compounding mass ratio of the polybasic acid in the solid content is 0.1 to 50%.
The method for producing a fibrous cellulose composite resin according to claim 1.
(Means according to claim 3)
At the time of the kneading treatment, amines were added and
The amount of the amines added is 1 to 200 parts by mass with respect to 100 parts by mass of the fibrous cellulose.
The method for producing a fibrous cellulose composite resin according to claim 1 or 2.
(Means according to claim 4)
It is assumed that the fibrous cellulose obtained by the dehydration treatment and the drying treatment contains a resin powder having an average particle size of 1 to 10,000 μm.
The method for producing a fibrous cellulose composite resin according to any one of claims 1 to 3.
(Means according to claim 5)
The fibrous cellulose obtained by the dehydration treatment and the drying treatment is made into a powder having an average particle size of 1 to 10,000 μm.
The method for producing a fibrous cellulose composite resin according to any one of claims 1 to 4.
(Means according to claim 6)
The fibrous cellulose obtained by the dehydration treatment and the drying treatment is made into a powder having a bulk specific density of 0.01 to 1.5.
The method for producing a fibrous cellulose composite resin according to any one of claims 1 to 5.
(Means according to claim 7)
A multi-screw kneader with two or more shafts is used for the kneading process.
The method for producing a fibrous cellulose composite resin according to any one of claims 1 to 6.
(Means according to claim 8)
The peripheral speed of the screw of the multi-screw kneader having two or more shafts is 0.2 to 200 m / min.
The method for producing a fibrous cellulose composite resin according to any one of claims 1 to 7.
(Means according to claim 9)
The ratio of the screw diameter of the multi-screw kneader having two or more shafts to the length of the kneading portion is 15 to 60.
The method for producing a fibrous cellulose composite resin according to any one of claims 1 to 8.
(Means according to claim 10)
It has an average fiber width of 0.1 to 15 μm, an average fiber length of 0.02 to 3.0 mm, a fibrillation rate of 1.0 to 30.0%, is modified with polybasic acid, and has a crystallinity of 90%. It is a kneaded product of fibrous cellulose and resin as described below.
The difference in solubility parameter (cal / cm ³ ) ^1/2 (SP value) between fibrous cellulose and resin is 10 to 0.1.
A fibrous cellulose composite resin characterized by this.

( Aspect 1)
It is a kneaded product of fibrous cellulose and resin having an average fiber width of 0.1 to 15 μm, an average fiber length of 0.02 to 3.0 mm, and a fibrillation rate of 1.0 to 30.0%.
The difference in solubility parameter (cal / cm ³ ) ^1/2 (SP value) between fibrous cellulose and resin is 10 to 0.1.
A fibrous cellulose composite resin characterized by this.

( Aspect 2)
The ratio of the fibrous cellulose having a fiber length of 0.2 mm or less is 12% or more.
The fibrous cellulose composite resin according to aspect 1.

構造式中のＲは、直鎖状、分枝鎖状、若しくは環状の飽和炭化水素基又はその誘導基；直鎖状、分枝鎖状、若しくは環状の不飽和炭化水素基又はその誘導基；芳香族基又はその誘導基；のいずれかである。 ( Aspect 3)
In the fibrous cellulose, a part or all of the hydroxyl groups are substituted with the functional groups represented by the following structural formula (1) or structural formula (2).
Fibrous cellulosic composite resin as defined in aspect 1 or aspect 2.

R in the structural formula is a linear, branched or cyclic saturated hydrocarbon group or an inducing group thereof; a linear, branched or cyclic unsaturated hydrocarbon group or an inducing group thereof; Either an aromatic group or an inducing group thereof;

( Aspect 4)
Containing the fibrous cellulose, the resin, and a polybasic acid.
The fibrous cellulose composite resin according to any one of aspects 1 to 3.

( Aspect 5)
The polybasic acid is at least one of phthalic acid and phthalic anhydride.
The fibrous cellulose composite resin according to aspect 4.

( Aspect 6)
The raw material fibers were defibrated with a refiner to obtain fibrous cellulose having an average fiber width of 0.1 to 15 μm, an average fiber length of 0.02 to 3.0 mm, and a fibrillation rate of 1.0 to 30.0%.
Knead with a resin having a difference in solubility parameter (cal / cm ³ ) ^{1/2 (SP value) from the fibrous cellulose of 10 to 0.1.}
A method for producing a fibrous cellulose composite resin.

( Aspect 7)
The fibrous cellulose, the resin, and the polybasic acid are kneaded, and the fibrous cellulose is modified with the polybasic acid during this kneading.
The method for producing a fibrous cellulose composite resin according to aspect 6.

( Aspect 8)
The fibrous cellulose and resin and a polybasic acid are kneaded to obtain a fibrous cellulose composite resin containing the polybasic acid.
The method for producing a fibrous cellulose composite resin according to aspect 6.

( Aspect 9)
Prior to the kneading, the fibrous cellulose is concentrated.
The method for producing a fibrous cellulose composite resin according to any one of aspects 6 to 8.

( Aspect 10)
Prior to or during the concentration, the resin powder is added to the fibrous cellulose.
The method for producing a fibrous cellulose composite resin according to aspect 9.

According to the present invention, there are a fibrous cellulose having a large reinforcing effect on the resin and a method for producing the same, and a fibrous cellulose composite resin having a high strength and a method for producing the same.

Next, a mode for carrying out the invention will be described. The embodiment of the present invention is an example of the present invention, and the scope of the present invention is not limited to the scope of the present embodiment.

The fibrous cellulose of the present embodiment has an average fiber width of 0.1 μm or more, an average fiber length of 0.02 to 3.0 mm, and a fibrillation rate of 1.0% or more. In one preferable form, a part or all of the hydroxyl groups of the cellulose fiber are substituted with the functional groups represented by the following structural formula (1) or structural formula (2).

構造式中のＲは、直鎖状、分枝鎖状、若しくは環状の飽和炭化水素基又はその誘導基；直鎖状、分枝鎖状、若しくは環状の不飽和炭化水素基又はその誘導基；芳香族基又はその誘導基；のいずれかである。

R in the structural formula is a linear, branched or cyclic saturated hydrocarbon group or an inducing group thereof; a linear, branched or cyclic unsaturated hydrocarbon group or an inducing group thereof; Either an aromatic group or an inducing group thereof;

Further, the fibrous cellulose composite resin of the present embodiment is a fibrous cellulose in which the above-mentioned average fiber width, average fiber length, and fibrillation rate are specified, or a kneaded product of the fibrous cellulose in which a hydroxyl group is substituted and the resin. Is. In addition, another form of the fibrous cellulose composite resin contains the fibrous cellulose and resin for which the above-mentioned average fiber width, average fiber length, and fibrillation rate are specified, and polybasic acid. Hereinafter, they will be described in order.

(Raw material fiber)
The fibrous cellulose having an average fiber width of 0.1 μm or more is microfiber cellulose, and can be obtained by refining (defibrating) the raw material fibers (pulp fibers). As the raw material fiber, one or more kinds can be selected and used from plant-derived fiber, animal-derived fiber, microorganism-derived fiber and the like. However, it is preferable to use pulp fiber which is a plant fiber. When the raw material fiber is pulp fiber, it is inexpensive and the problem of thermal recycling can be avoided.

Plant-derived fibers include wood pulp made from broadleaf trees, coniferous trees, etc., non-wood pulp made from straw bagasse, etc., recovered waste paper, used paper pulp made from waste paper, etc. (DIP). Species or two or more species can be selected and used.

As the wood pulp, select one or more from chemical pulp such as hardwood kraft pulp (LKP) and softwood kraft pulp (NKP), mechanical pulp (TMP), and used paper pulp (DIP). Can be done. These pulps are pulps used for papermaking, and by using these pulps, existing equipment can be effectively utilized.

The hardwood kraft pulp (LKP) may be hardwood bleached kraft pulp, hardwood unbleached kraft pulp, or hardwood semi-bleached kraft pulp. Similarly, the softwood kraft pulp (NKP) may be softwood bleached kraft pulp, softwood unbleached kraft pulp, or softwood semi-bleached kraft pulp.

Further, the used paper pulp (DIP) may be magazine used paper pulp (MDIP), newspaper used paper pulp (NDIP), stepped used paper pulp (WP), or other used paper pulp. good.

Further, as the mechanical pulp, for example, stone ground pulp (SGP), pressurized stone ground pulp (PGW), refiner ground pulp (RGP), chemi-grand pulp (CGP), thermo-grand pulp (TGP), ground pulp (GP). ), Thermomechanical pulp (TMP), Chemithermomechanical pulp (CTMP), Refiner mechanical pulp (RMP), Bleached thermomechanical pulp (BTMP), etc. can be selected and used. ..

(Pretreatment process)
The raw material fibers are preferably pretreated by a chemical method. By pretreating by a chemical method prior to the pulverization (defibration) treatment, the number of pulverization treatments can be significantly reduced, and the energy of the pulverization treatment can be significantly reduced.

Pretreatment by chemical method includes hydrolysis of polysaccharide with acid (acid treatment), hydrolysis of polysaccharide with enzyme (enzyme treatment), swelling of polysaccharide with alkali (alkali treatment), oxidation of polysaccharide with oxidizing agent (oxidation treatment). ), Reduction of polysaccharides with a reducing agent (reduction treatment), and the like can be exemplified.

By applying an alkali treatment prior to the micronization treatment, some of the hydroxyl groups of hemicellulose and cellulose possessed by the pulp are dissociated, and the molecules are anionized to weaken the intramolecular and intermolecular hydrogen bonds. Has the effect of promoting the dispersion of.

As the alkali, for example, organic alkalis such as sodium hydroxide, lithium hydroxide, potassium hydroxide, aqueous ammonia, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrabutylammonium hydroxide, and benzyltrimethylammonium hydroxide are used. However, from the viewpoint of manufacturing cost, it is preferable to use sodium hydroxide.

When an enzyme treatment, an acid treatment, or an oxidation treatment is performed prior to the micronization treatment, the water retention degree of the microfiber cellulose can be lowered, the crystallization degree can be increased, and the homogeneity can be increased. In this regard, it is considered that the lower the water retention level of the microfiber cellulose, the better the dispersibility in the resin, and the higher the homogeneity of the microfiber cellulose, the less the defect that causes the destruction of the resin composition, and as a result, the ductility of the resin. It is considered that a resin composition having a high strength capable of retaining the above-mentioned material can be obtained. In addition, the enzyme treatment, acid treatment, and oxidation treatment decompose the hemicellulose and the amorphous region of cellulose in the pulp, and as a result, the energy of the micronization treatment can be reduced, and the homogeneity and dispersibility of the fibers are improved. be able to. Moreover, if the proportion of the cellulose crystal region, which is considered to be rigid and has low water retention, in the entire fiber, the molecular chains are aligned, the dispersibility is improved and the aspect ratio is expected to decrease, but the ductility is maintained. At the same time, a resin composition having high mechanical strength can be obtained.

Among the above-mentioned various treatments, it is preferable to carry out an enzyme treatment, and in addition, it is more preferable to carry out one or more treatments selected from an acid treatment, an alkali treatment and an oxidation treatment. Hereinafter, the alkali treatment will be described in detail.

As a method of alkaline treatment, for example, there is a method of immersing the raw material fiber in an alkaline solution.

The alkaline compound contained in the alkaline solution may be an inorganic alkaline compound or an organic alkaline compound. Examples of the inorganic alkali compound include hydroxides of alkali metals or alkaline earth metals, carbonates of alkali metals or alkaline earth metals, phosphoroxates of alkali metals or alkaline earth metals, and the like. Further, as the hydroxide of the alkali metal, for example, lithium hydroxide, sodium hydroxide, potassium hydroxide and the like can be exemplified. Examples of the hydroxide of the alkaline earth metal include calcium hydroxide and the like. Examples of the alkali metal carbonate include lithium carbonate, lithium hydrogen carbonate, potassium carbonate, potassium hydrogen carbonate, sodium carbonate, sodium hydrogen carbonate and the like. Examples of the carbonate of the alkaline earth metal include calcium carbonate and the like. Examples of the alkali metal phosphate include lithium phosphate, potassium phosphate, trisodium phosphate, disodium hydrogen phosphate and the like. Examples of the alkali earth metal phosphate include calcium phosphate, calcium hydrogen phosphate, and the like.

Examples of the organic alkaline compound include ammonia, aliphatic amines, aromatic amines, aliphatic ammonium, aromatic ammonium, heterocyclic compounds and their hydroxides, carbonates and phosphates. Specifically, for example, for example, ammonia, hydrazine, methylamine, ethylamine, diethylamine, triethylamine, propylamine, dipropylamine, butylamine, diaminoethane, diaminopropane, diaminobutane, diaminopentane, diaminohexane, cyclohexylamine, aniline. , Tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, benzyltrimethylammonium hydroxide, pyridine, N, N-dimethyl-4-aminopyridine, ammonium carbonate, ammonium hydrogencarbonate, Examples thereof include diammonium hydrogen phosphate.

The solvent of the alkaline solution may be either water or an organic solvent, but it is preferably a polar solvent (a polar organic solvent such as water or alcohol), and more preferably an aqueous solvent containing at least water.

The pH of the alkaline solution at 25 ° C. is preferably 9 or higher, more preferably 10 or higher, and particularly preferably 11-14. When the pH is 9 or more, the yield of MFC is high. However, if the pH exceeds 14, the handleability of the alkaline solution deteriorates.

(Miniaturization (defibration) process)
For the micronization treatment, for example, a beater, a high-pressure homogenizer, a homogenizer such as a high-pressure homogenizer, a millstone friction machine such as a grinder and a grinder, a single-screw kneader, a multi-screw kneader, a kneader refiner, etc. It can be done by beating, and it is preferable to use a refiner.

The refiner is a device for beating pulp fibers, and a known device can be used. As the refiner, a conical type, a double disc refiner (DDR) and a single disc refiner (SDR) are preferable from the viewpoint of efficiently applying a shearing force to the pulp fiber and advancing preliminary defibration. .. It is also preferable to use a refiner in the defibration treatment step from the viewpoint that separation and washing after the treatment are not required.

The microfiber cellulose is a fiber made of cellulose or a derivative of cellulose. Ordinary microfiber cellulose has strong hydration property, and by hydrating in an aqueous medium, it stably maintains a dispersed state (state of a dispersion liquid). The single fibers constituting the microfiber cellulose may form a fibrous form by aggregating a plurality of strips in an aqueous medium.

The micronization (defibration) treatment is preferably carried out in a range in which the number average fiber diameter (fiber width; average diameter of single fibers) of the microfiber cellulose is 0.1 μm or more, and is in the range of 0.1 to 15 μm. It is more preferable to carry out in the range of 0.2 to 10 μm, and it is particularly preferable to carry out in the range of 0.2 to 10 μm. The strength of the fibrous cellulose composite resin is improved by carrying out the process within a range in which the number average fiber diameter (width) is 0.1 μm or more.

Specifically, when the average fiber diameter is less than 0.1 μm, it is no different from that of cellulose nanofibers, and the reinforcing effect (particularly the flexural modulus) cannot be sufficiently obtained. In addition, the miniaturization processing time becomes long, a large amount of energy is required, which leads to an increase in manufacturing cost. On the other hand, when the average fiber diameter exceeds 15 μm, the dispersibility of the fibers tends to be inferior. If the dispersibility of the fibers is insufficient, the reinforcing effect tends to be inferior.

The average fiber length (length of single fiber) of the microfiber cellulose is preferably 0.02 to 3 mm, more preferably 0.05 to 2 mm, and preferably 0.1 to 1.5 mm. Especially preferable. If the average fiber length is less than 0.02 mm, a three-dimensional network of fibers cannot be formed, and the reinforcing effect may be significantly reduced. The average fiber length can be arbitrarily adjusted by, for example, selection of raw material fibers, pretreatment, and defibration treatment.

In the present embodiment, the fiber length of the microfiber cellulose is preferably 0.2 mm or less in a proportion of 12% or more, more preferably 16% or more, and particularly preferably 26% or more. If the ratio is less than 12%, a sufficient reinforcing effect cannot be obtained. There is no upper limit to the ratio of microfiber cellulose to 0.2 mm or less, and all of them may be 0.2 mm or less.

The aspect ratio of the microfiber cellulose is preferably 2 to 30,000, more preferably 10 to 10,000 in order to improve the mechanical strength while maintaining the ductility of the resin to some extent.

The aspect ratio is a value obtained by dividing the average fiber length by the average fiber width. It is considered that the larger the aspect ratio, the more places in the resin where the resin is caught, so that the reinforcing effect is improved, but on the other hand, the greater the number of catches, the lower the ductility of the resin. It should be noted that when an inorganic filler is kneaded into a resin, it is known that the larger the aspect ratio of the filler, the higher the tensile strength, but the tensile elongation at break is significantly reduced.

In the present embodiment, the fibrillation rate of the microfiber cellulose is preferably 1.0% or more, more preferably 1.5% or more, and particularly preferably 2.0% or more. The fibrillation rate is preferably 30.0% or less, more preferably 20.0% or less, and particularly preferably 15.0% or less. If the fibrillation rate is 30.0% or more, the miniaturization progresses too much and the fibers become nanofibers, so that the intended effect may not be obtained. On the other hand, when the fibrillation rate is less than 1.0%, there are few hydrogen bonds between the fibrils, and a strong three-dimensional network becomes insufficient. In this regard, the present inventors have conducted various tests to construct a stronger three-dimensional network by hydrogen-bonding the fibrils of the microfiber cellulose to each other when the fibrillation rate of the microfiber cellulose is set to 1.0% or more. Found in the process. It was also found that when the fibrillation rate is increased, the interface in contact with the resin increases, but when the polybasic acid is used as a compatibilizer or for hydrophobic modification, the reinforcing effect is further improved.

The fibrillation rate refers to the dissociation of cellulose fibers in accordance with JIS-P-8220: 2012 "Pulp-Dissolution Method", and the obtained dissociated pulp is referred to as FiberLab. (Kajaani) means a value measured using.

The crystallinity of the microfiber cellulose is preferably 50% or more, more preferably 55% or more, and particularly preferably 60% or more. When the crystallinity is less than 50%, the compatibility with the resin is improved, but the strength of the fiber itself is lowered, so that the reinforcing effect of the resin composition tends to be inferior.

On the other hand, the crystallinity of the microfiber cellulose is preferably 90% or less, more preferably 88% or less, and particularly preferably 86% or less. When the crystallinity exceeds 90%, the ratio of strong hydrogen bonds in the molecule increases and the fiber itself becomes rigid, but the compatibility with the resin decreases, and the reinforcing effect of the resin composition tends to be inferior. In addition, it tends to be difficult to chemically modify microfiber cellulose. The crystallinity can be arbitrarily adjusted by, for example, selection of raw material fibers, pretreatment, and miniaturization treatment.

The pulp viscosity of the microfiber cellulose is preferably 2 cps or more, and more preferably 4 cps or more. When the pulp viscosity is less than 2 cps, when the microfiber cellulose is kneaded with the resin, the aggregation of the microfiber cellulose cannot be sufficiently suppressed, and the reinforcing effect of the resin composition tends to be inferior.

The freeness of the microfiber cellulose is preferably 500 cc or less, more preferably 300 cc or less, and particularly preferably 100 cc or less. If it exceeds 500 cc, the fiber width of the microfiber cellulose exceeds 15 μm, and the reinforcing effect is not sufficient.

(Kneading, etc.)
The microfiber cellulose obtained by the micronization treatment can be dispersed in an aqueous medium to prepare a dispersion liquid, if necessary. It is particularly preferable that the entire amount of the aqueous medium is water, but an aqueous medium which is another liquid which is partially compatible with water can also be preferably used. As the other liquid, lower alcohols having 3 or less carbon atoms can be used.

The dispersion is preferably concentrated to adjust the solid content concentration. The solid content concentration of this dispersion is preferably 1.0% by mass or more, more preferably 1.5% by mass or more, and particularly preferably 2.0% by mass or more. The solid content concentration of the dispersion is preferably 70% by mass or less, more preferably 60% by mass or less, and particularly preferably 50% by mass or less. If the solid content concentration is less than 1.0% by mass, the concentration may be lower than the concentration of the microfiber cellulose aqueous dispersion obtained by the micronization treatment. On the other hand, if the solid content concentration exceeds 70% by mass, it becomes difficult to dilute and disperse thereafter, and it may be difficult to mix with a polybasic acid, a resin powder, or other compositions.

The microfiber cellulose may be dehydrated and dried prior to kneading. The dehydration / drying treatment of the microfiber cellulose may or may not be performed together with the kneading treatment or the like. Further, the dehydration treatment and the drying treatment may be performed together or separately.

The fibrous cellulose of this embodiment may or may not be modified by a polybasic acid or the like. When modified with a polybasic acid, the water content (moisture content) of the dehydrated / dried microfiber cellulose is preferably 5% or less, more preferably 3% or less, further preferably 1% or less, and particularly preferably 0%. If the water content exceeds 5%, the microfiber cellulose may not be denatured by the polybasic acid. In addition, if the water content is high, the energy required for kneading becomes enormous, which is uneconomical.

On the other hand, when not modified by polybasic acid, the water content of the dehydrated / dried microfiber cellulose is preferably more than 5%, more preferably 8% or more, and particularly preferably 10% or more. When the water content exceeds 5%, the denaturation of the cellulose fibers by the polybasic acid does not proceed, and the obtained composite resin contains the polybasic acid.

For dehydration treatment, for example, select one or more from belt press, screw press, filter press, twin roll, twin wire former, valveless filter, center disk filter, membrane treatment, centrifuge and the like. Can be used.

The drying treatment includes, for example, rotary kiln drying, disk type drying, air flow type drying, medium flow drying, spray drying, drum drying, screw conveyor drying, paddle type drying, uniaxial kneading drying, multiaxial kneading drying, vacuum drying, stirring drying. One type or two or more types can be selected and used from the above.

A pulverization treatment step may be added after the dehydration / drying treatment step. For the pulverization treatment, for example, one type or two or more types can be selected and used from among bead mills, kneaders, dispersers, twist mills, cut mills, hammer mills and the like.

The shape of the dehydrated / dried microfiber cellulose can be powder, pellet, sheet or the like. However, powder is preferable.

In the powder form, the average particle size of the microfiber cellulose is preferably 10,000 to 1 μm, more preferably 5,000 to 10 μm, and particularly preferably 1,000 to 100 μm. If the average particle size exceeds 10,000 μm, it may not enter the kneading device because the particle size is large. On the other hand, if the average particle size is less than 1 μm, energy is required for the pulverization process, which is not economical.

In the powder form, the bulk specific gravity of the microfiber cellulose is preferably 1.5 to 0.01, more preferably 1 to 0.04, and particularly preferably 0.5 to 0.1. If the bulk specific density exceeds 1.5, it means that the specific gravity of cellulose exceeds 1.5, which is physically difficult to realize. On the other hand, setting the bulk specific density to less than 0.01 is disadvantageous in terms of transfer cost.

The dehydrated and dried microfiber cellulose may contain a resin. When the resin is contained, the hydrogen bonds between the dehydrated and dried microfiber celluloses are inhibited, and the dispersibility in the resin at the time of kneading can be improved. Therefore, this resin can be added before or after the above-mentioned concentration of the dispersion liquid or dehydration / drying of the microfiber cellulose, or at the time of kneading.

Examples of the form of the resin contained in the dehydrated / dried microfiber cellulose include powder, pellet, and sheet. However, powder (powdered resin) is preferable.

In the case of powder, the average particle size of the resin powder contained in the dehydrated and dried microfiber cellulose is preferably 10,000 to 1 μm, more preferably 5,000 to 10 μm, and particularly preferably 1,000 to 100 μm. If the average particle size exceeds 10,000 μm, it may not enter the kneading device due to the large particle size. On the other hand, if the average particle size is less than 1 μm, hydrogen bonds between microfiber celluloses may not be inhibited due to the fineness.

The microfiber cellulose obtained as described above is kneaded with a resin to obtain a kneaded product. At the time of this kneading, a polybasic acid is further added to modify the cellulose fibers with the polybasic acid, or the kneaded product contains the polybasic acid. As described above, the water content (moisture content) of the microfiber cellulose at the time of kneading is important.

As the resin, either a thermoplastic resin or a thermosetting resin can be used.

Examples of the thermoplastic resin include polyolefins such as polypropylene (PP) and polyethylene (PE), polyester resins such as aliphatic polyester resins and aromatic polyester resins, polyacrylic resins such as polystyrene, methacrylate and acrylate, and polyamide resins. One type or two or more types can be selected and used from polycarbonate resin, polyacetal resin and the like.

However, it is preferable to use at least one of polyolefin and polyester resin. Moreover, it is preferable to use polypropylene as the polyolefin. As the polypropylene, one type or two or more types can be selected and used from homopolymers, random polymers, and block polymers. Further, as the polyester resin, examples of the aliphatic polyester resin include polylactic acid and polycaprolactone, and examples of the aromatic polyester resin include polyethylene terephthalate, which are biodegradable. It is preferable to use a polyester resin having the above (also referred to simply as “biodegradable resin”).

As the biodegradable resin, for example, one or more of hydroxycarboxylic acid-based aliphatic polyester, caprolactone-based aliphatic polyester, dibasic acid polyester and the like can be selected and used.

As the hydroxycarboxylic acid-based aliphatic polyester, for example, homopolymers of hydroxycarboxylic acids such as lactic acid, malic acid, glucose acid, and 3-hydroxybutyric acid, and at least one of these hydroxycarboxylic acids are used together. One kind or two or more kinds can be selected and used from the polymer and the like. However, it is preferable to use polylactic acid, a copolymer of lactic acid and the above-mentioned hydroxycarboxylic acid excluding lactic acid, polycaprolactone, or a copolymer of at least one of the above-mentioned hydroxycarboxylic acids and caprolactone, and polylactic acid is used. Especially preferred to use.

As the lactic acid, for example, L-lactic acid, D-lactic acid and the like can be used, and these lactic acids may be used alone or two or more kinds may be selected and used.

As the caprolactone-based aliphatic polyester, for example, one or more can be selected and used from a homopolymer of polycaprolactone, a copolymer of polycaprolactone and the like and the above-mentioned hydroxycarboxylic acid, and the like. ..

As the dibasic acid polyester, for example, one or more of polybutylene succinate, polyethylene succinate, polybutylene adipate and the like can be selected and used.

As the biodegradable resin, one type may be used alone, or two or more types may be used in combination.

Examples of the thermosetting resin include phenol resin, urea resin, melamine resin, furan resin, unsaturated polyester, diallyl phthalate resin, vinyl ester resin, epoxy resin, urethane resin, silicone resin, thermosetting polyimide resin and the like. Can be used. These resins can be used alone or in combination of two or more.

The resin may preferably contain an inorganic filler in a proportion that does not interfere with thermal recycling.

Examples of the inorganic filler include simple substances of metal elements in Groups I to VIII of the Periodic Table, such as Fe, Na, K, Cu, Mg, Ca, Zn, Ba, Al, Ti, and silicon elements, and oxidation. Examples thereof include substances, hydroxides, carbon salts, sulfates, silicates, sulfites, and various clay minerals composed of these compounds.

Specifically, for example, barium sulfate, calcium sulfate, magnesium sulfate, sodium sulfate, calcium sulfite, zinc oxide, silica, heavy calcium carbonate, light calcium carbonate, aluminum borate, alumina, iron oxide, calcium titanate, hydroxide. Examples of aluminum, magnesium hydroxide, calcium hydroxide, sodium hydroxide, magnesium carbonate, calcium silicate, clay walastonite, glass beads, glass powder, silica sand, silica stone, quartz powder, diatomaceous earth, white carbon, glass fiber and the like are exemplified. be able to. A plurality of these inorganic fillers may be contained. Further, it may be contained in used paper pulp.

The blending ratio of the microfiber cellulose and the resin is preferably 1 part by mass or more for the microfiber cellulose and 99 parts by mass or less for the resin, and 2 parts by mass or more for the microfiber cellulose and 98 parts by mass or less for the resin. More preferably, the amount of microfiber cellulose is 3 parts by mass or more, and the amount of resin is 97 parts by mass or less.

Further, the amount of microfiber cellulose is preferably 50 parts by mass or less and the amount of resin is 50 parts by mass or more, more preferably 40 parts by mass or less of microfiber cellulose and 60 parts by mass or more of resin, and 30 parts by mass of microfiber cellulose. It is particularly preferable that the amount of the resin is 70 parts by mass or less and 70 parts by mass or less. However, when the blending ratio of the microfiber cellulose is 10 to 50 parts by mass, the strength of the resin composition, particularly the bending strength and the tensile elastic modulus can be remarkably improved.

The content ratio of the microfiber cellulose and the resin finally obtained in the resin composition is usually the same as the above-mentioned blending ratio of the microfiber cellulose and the resin.

When modifying microfiber cellulose, examples thereof include hydrophobic modification such as esterification, etherification, amidation, and sulfidation. However, as a method for hydrophobically modifying microfiber cellulose, esterification is preferably adopted.

As a method of esterification, for example, esterification with a hydrophobic agent such as carboxylic acid, carboxylic acid halide, acetic acid, propionic acid, acrylic acid, methacrylic acid, phosphoric acid, sulfonic acid, polybasic acid anhydride and derivatives thereof. Can be mentioned. However, as the hydrophobizing agent, it is preferable to use anhydrous polybasic acid or a derivative thereof.

(Polybasic acid)
Polybasic acids to be kneaded with microfiber cellulose and resins include oxalic acids, phthalates, malonic acids, succinic acids, glutaric acids, adipic acids, tartaric acids, glutamates, sebacic acids, hexafluorosilicates, maleic acids, and itaconic acids. One or more can be selected and used from acids, citraconic acids, citric acids and the like. However, it is preferable that at least one or more of phthalic acid, phthalates and derivatives of these (phthalates) are used.

Examples of phthalates (derivatives) include phthalic acid, potassium hydrogen phthalate, sodium hydrogen phthalate, sodium phthalate, ammonium phthalate, dimethyl phthalate, diethyl phthalate, diallyl phthalate, diisobutyl phthalate, and dinormal hexyl phthalate. , Dioctyl phthalate, diisononyl phthalate, diisodecyl phthalate, ditriisodecyl phthalate and the like. Preferably, phthalic acid is used.

As the maleic anhydride, for example, one or more of maleic anhydride, phthalic anhydride, itaconic anhydride, citraconic anhydride, citric acid anhydride and the like can be selected and used. However, it is preferable to use maleic anhydride, and more preferably phthalic anhydride.

Examples of phthalic anhydrides include phthalic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, hydroxyphthalic anhydride, hexahydrophthalic anhydride, 4-ethynylphthalic anhydride, 4-phenylethynyl. Phthalic anhydride can be mentioned. However, it is preferable to use phthalic anhydride.

When polybasic anhydride is used, when the cellulose fiber is modified, a part of the hydroxyl group is replaced by a predetermined functional group, and the compatibility between the microfiber cellulose and the resin is improved. Further, when the polybasic acid is simply contained, the polybasic acid functions as a compatibilizer and the compatibility is improved. As a result, the strength of the obtained fibrous cellulose composite resin, particularly the bending strength, is improved.

When the polybasic acid functions as a compatibilizer, the progress of denaturation of the cellulose fibers does not matter, so that the quality of the obtained composite resin is stabilized. However, care must be taken not to denature the cellulose fibers by paying attention to the water content of the microfiber cellulose during kneading (this point is as described above).

The modification of the microfiber cellulose is preferably carried out so that a part of the hydroxyl groups of the cellulose constituting the fiber is replaced with the functional group represented by the following structural formula (1) or structural formula (2).

構造式中のＲは、直鎖状、分枝鎖状、若しくは環状の飽和炭化水素基又はその誘導基；直鎖状、分枝鎖状、若しくは環状の不飽和炭化水素基又はその誘導基；芳香族基又はその誘導基；のいずれかである。

R in the structural formula is a linear, branched or cyclic saturated hydrocarbon group or an inducing group thereof; a linear, branched or cyclic unsaturated hydrocarbon group or an inducing group thereof; Either an aromatic group or an inducing group thereof;

As the anhydrous polybasic acid, it is preferable to use one having the following structural formula (3) or structural formula (4).

構造式中のＲは、直鎖状、分枝鎖状、若しくは環状の飽和炭化水素基又はその誘導基；直鎖状、分枝鎖状、若しくは環状の不飽和炭化水素基又はその誘導基；芳香族基又はその誘導基；のいずれかである。

R in the structural formula is a linear, branched or cyclic saturated hydrocarbon group or an inducing group thereof; a linear, branched or cyclic unsaturated hydrocarbon group or an inducing group thereof; Either an aromatic group or an inducing group thereof;

By using the polybasic anhydride represented by the structural formula (3) or the structural formula (4), the compatibility between the microfiber cellulose and the thermoplastic resin is improved.

For the kneading process, for example, one or two or more types are selected and used from a single-screw or bi-screw multi-screw kneader, a mixing roll, a kneader, a roll mill, a Banbury mixer, a screw press, a disperser, and the like. be able to. Among them, it is preferable to use a multi-screw kneader with two or more shafts. One or more multi-axis kneaders having two or more axes may be used in parallel or in series.

The peripheral speed of the screw of the multi-screw kneader having two or more shafts is preferably 0.2 to 200 m / min, more preferably 0.5 to 150 m / min, and particularly preferably 1 to 100 m / min. If the peripheral speed is less than 0.2 m / min, the microfiber cellulose cannot be dispersed well in the resin. On the other hand, when the peripheral speed exceeds 200 m / min, the shearing force on the microfiber cellulose becomes excessive and the reinforcing effect cannot be obtained.

The ratio of the screw diameter of the kneader used in this embodiment to the length of the kneading portion is preferably 15 to 60. If the ratio is less than 15, the kneaded portion is short and there is a possibility that the microfiber cellulose and the resin cannot be mixed. If the ratio exceeds 60, the kneaded portion is too long, so that the shear load on the microfiber cellulose becomes high, and the reinforcing effect may not be obtained.

The temperature of the kneading treatment is equal to or higher than the glass transition point of the resin and varies depending on the type of resin, but is preferably 80 to 280 ° C, more preferably 90 to 260 ° C, and 100 to 240 ° C. Is particularly preferable.

The blending mass ratio of the microfiber cellulose in the composite resin in terms of solid content is preferably 70% to 1%, more preferably 50% to 5%, and particularly preferably 40% to 10%. ..

When used for denaturation, the compounding mass ratio of the polybasic acid in the solid content is preferably 0.1 to 50%, more preferably 1 to 30%, and preferably 2 to 20%. Especially preferable. The same applies to the case where it functions as a compatibilizer.

At the time of kneading, polypropylene maleic anhydride may be added. The amount of polypropylene maleic anhydride added is preferably 1 to 1000% by mass, more preferably 5 to 500% by mass, and particularly preferably 10 to 200% by mass, with the blending amount of microfiber cellulose as 100. If the amount added is less than 1% by mass, the effect is insufficient. On the other hand, if the addition amount exceeds 1000% by mass, the addition may be excessive, and conversely, the strength of the resin matrix may be lowered.

At the time of kneading, amines may be added as a method of adjusting the pH of the microfiber cellulose slurry. Examples of amines include methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, ethylenediamine, triethanolamine, N, N-dimethylpropane-2-amine, tetramethylethyleneamine, hexamethylamine, spermidine, and spermin. , Amantazine, aniline, phenethylamine, toluidine, catecholamine, 1,8-bis (dimethylamino) naphthalene, pyrrolidine, piperidine, piperazine, morpholin, quinuclidine, pyrrol, pyrazole, imidazole, pyridine, pyridazine, pyrimidine, pyrazine, oxazole, thiazole, Examples thereof include 4-dimethylaminopyridine.

The amount of amines added is preferably 1 to 1,000% by mass, more preferably 5 to 500% by mass, and particularly preferably 10 to 200% by mass, with the blending amount of microfiber cellulose as 100. If the amount added is less than 1% by mass, the pH adjustment is insufficient. On the other hand, if the addition amount exceeds 200% by mass, the addition may be excessive, and conversely, the strength of the resin matrix may be lowered.

Examples of the solvent for hydrophobically modifying microfiber cellulose include no solvent, a protic polar solvent, an aprotic polar solvent, a non-polar solvent, and a resin. However, it is preferable to use a resin as the solvent, and in this embodiment, the solvent is substantially unnecessary because it is modified when kneaded with the resin.

As the protic polar solvent, formic acid, butanol, isobutanol, nitromethane, ethanol, methanol, acetic acid, water and the like can be used, for example.

As the aprotic polar solvent, for example, N-methylpyrrolidone, tetrahydrofuran, ethyl acetate, acetone, dimethylformamide, acetonitrile, dimethyl sulfoxide, propylene carbonate and the like can be used.

As the non-polar solvent, for example, hexane, benzene, toluene, chloroform, diethyl ether, dichloromethane, etc. can be used.

If the difference in solubility parameter (cal / cm ³ ) ^1/2 (SP value) between microfiber cellulose and resin, that is, the SP _MFC value of microfiber cellulose and the SP _POL value of resin, the difference in SP value = SP _MFC value It can be a −SP _{POL value.} The difference in SP value is preferably 10 to 0.1, more preferably 8 to 0.5, and particularly preferably 5 to 1. If the difference in SP value exceeds 10, the microfiber cellulose is not dispersed in the resin, and the reinforcing effect cannot be obtained. On the other hand, if the difference in SP value is less than 0.1, the microfiber cellulose dissolves in the resin and does not function as a filler, so that a reinforcing effect cannot be obtained. _{In this respect, the smaller the difference between the SP POL} value of the resin (solvent) _{and the SP MFC} value of the microfiber cellulose (solute), the greater the reinforcing effect. The solubility parameter (cal / cm ³ ) ^1/2 (SP value) is a measure of the intermolecular force acting between the solvent and the solute, and the closer the SP value is to the solvent and solute, the higher the solubility. ..

(Other compositions)
Microfiber cellulose includes one or more of various fine fibers called cellulose nanofibers, microfibril cellulose, microfibril-like fine fibers, microfiber cellulose, microfibrillated cellulose, super microfibril cellulose and the like. Can be included, and these fine fibers may be included. Further, it is also possible to include fibers in which these fine fibers are further refined, and may be contained. However, it is necessary to make the ratio of microfiber cellulose in all raw material fibers 10% by mass or more, preferably 30% by mass or more, and more preferably 60% by mass or more.

In addition to the above, kenaf, jute hemp, Manila hemp, sisal hemp, goose bark, sansho, 楮, banana, pineapple, coco palm, corn, sugar cane, bagasse, palm, papyrus, reed, esparto, survivor grass, wheat, rice, bamboo, Fibers derived from plant materials obtained from various plants such as various conifers (such as sugi and hinoki), broad-leaved trees and cotton may be included, and may be included.

As the raw material of the microfiber cellulose composite resin, in addition to the microfiber cellulose and the resin, for example, one or more of antistatic agents, flame retardants, antibacterial agents, colorants, radical scavengers, foaming agents and the like are used. It can be selected and used as long as the effect of the present invention is not impaired.

These raw materials may be kneaded together with the dispersion liquid of the microfiber cellulose, the microfiber cellulose and the resin, kneaded with these kneaded products, or kneaded by another method. However, from the viewpoint of production efficiency, it is preferable to knead the microfiber cellulose and the resin together with the kneading.

The resin may contain an ethylene-α-olefin copolymer elastomer or a styrene-butadiene block copolymer. Examples of α-olefins include butene, isobutene, pentane, hexene, methyl-pentene, octene, decene, dodecene and the like.

(Molding process)
The microfiber cellulose and the resin (kneaded product) are kneaded again if necessary, and then molded into a desired shape. Even if the modified microfiber cellulose is dispersed in the kneaded product, the molding processability is excellent.

The size, thickness, shape, etc. of the molding are not particularly limited, and may be, for example, a sheet shape, a pellet shape, a powder shape, a fibrous shape, or the like.

The temperature during the molding process is equal to or higher than the glass transition point of the resin and varies depending on the type of resin, but is preferably 80 to 280 ° C, more preferably 90 to 260 ° C, and 100 to 240 ° C. It is particularly preferable to do so.

As the molding processing device, for example, one or more types from injection molding machines, blow molding machines, hollow molding machines, blow molding machines, compression molding machines, extrusion molding machines, vacuum molding machines, pressure molding machines, and the like. Can be selected and used.

The molding process can be performed by a known molding method, for example, mold molding, injection molding, extrusion molding, hollow molding, foam molding, or the like. It is also possible to spin the kneaded product into a fibrous form and mix it with the above-mentioned plant material or the like to form a mat shape or a board shape. The mixed fiber can be produced by, for example, a method of simultaneously depositing with an air ray.

In addition, this molding process can be performed after the kneading process, or the kneaded product is once cooled and made into chips by using a crusher or the like, and then the chips are used in a molding machine such as an extrusion molding machine or an injection molding machine. It can also be thrown in.

(Definition of terms, measurement method, etc.)
Unless otherwise specified, the terms in the specification are as follows.

(Average fiber diameter)
100 ml of an aqueous dispersion of microfiber cellulose having a solid content concentration of 0.01 to 0.1% by mass is filtered through a membrane filter manufactured by Teflon (registered trademark), and the solvent is replaced once with 100 ml of ethanol and three times with 20 ml of t-butanol. .. Next, it is freeze-dried and coated with osmium to prepare a sample. This sample is observed by an electron microscope SEM image at a magnification of 5000 times, 10000 times, or 30000 times depending on the width of the constituent fibers. Specifically, two diagonal lines are drawn on the observation image, and three straight lines passing through the intersections of the diagonal lines are arbitrarily drawn. Further, the width of a total of 100 fibers intersecting with these three straight lines is visually measured. Then, the median diameter of the measured value is taken as the average fiber diameter.

(Fiber analysis)
The average fiber length and the fibrillation rate are measured by a fiber analyzer "FS5" manufactured by Valmet.

(aspect ratio)
It is a value obtained by dividing the average fiber length by the average fiber width (diameter).

(Crystallinity)
It is a value measured by an X-ray diffraction method in accordance with the "general rule of X-ray diffraction analysis" of JIS-K0131 (1996). The microfiber cellulose has an amorphous portion and a crystalline portion, and the crystallinity means the ratio of the crystalline portion to the entire microfiber cellulose.

(Pulp viscosity)
Measure according to JIS-P8215 (1998). The higher the pulp viscosity, the higher the degree of polymerization of the microfiber cellulose.

(Freeness)
It is a value measured according to JIS P8121-2: 2012.

(Moisture content (moisture content))
The water content of the fiber is a value calculated by the following formula, with the mass at the time when the sample is held at 105 ° C. for 6 hours or more at 105 ° C. and no change in mass is observed using a constant temperature dryer as the mass after drying.
Fiber moisture content (%) = [(mass before drying-mass after drying) ÷ mass before drying] x 100

Next, an example of the present invention will be shown, and when the action and effect of the present invention, that is, when polybasic acid is used, microfiber cellulose (MFC) is used, and in particular, MFC having a predetermined fibrillation rate is used. , It will be clarified that the reinforcing effect of the resin is superior to that of using cellulose nanofiber (CNF).

(Example 1)
7 g of phthalic acid and 83 g of polypropylene powder were added to 365 g of an aqueous dispersion of microfiber cellulose (using a refiner for defibration) having a solid content concentration of 2.75% by weight, and the mixture was dried by heating at 105 ° C. to obtain a mixture. The water content of the mixture was less than 10%. The mixture was kneaded with a twin-screw kneader under the conditions of 180 ° C. and 200 rpm to obtain a fibrous cellulose composite resin. This composite resin was cut into a cylinder having a diameter of 2 mm and a length of 2 mm with a pelleter, and injection-molded into a rectangular parallelepiped test piece (length 59 mm, width 9.6 mm, thickness 3.8 mm) at 180 ° C. Table 1 shows the test results of the bending test for the obtained molded product. The evaluation method of the bending test is as follows.

(Bending test)
The flexural modulus was measured according to JIS K7171: 2008. In the table, the evaluation results are shown according to the following criteria.
When the flexural modulus (magnification) of the composite resin is 1.5 times or more, assuming that the flexural modulus of the resin itself is 1.
When the flexural modulus (magnification) of the composite resin is less than 1.5 times, where the flexural modulus of the resin itself is 1.

(Other Examples and Comparative Examples)
Number of refiner treatments, fiber width of fibrous cellulose, fiber length, fibrillation rate, and fiber moisture content, blending ratio of fibers (cellulose), phthalic acid, and resin during kneading, and added polybasic acid (chemicals) The test was conducted by changing the type, presence / absence, etc. as shown in Table 1. The results are shown in Table 1. The polybasic acid was basically added immediately before kneading, but in Example 9, it was added to the dispersion liquid of fibrous cellulose.

(Discussion)
From Table 1, it can be seen that when a polybasic acid is used, it is preferable to use MFC rather than CNF, and the fibrillation rate is an important factor.

The present invention can be used as a fibrous cellulose and a method for producing the same, and a fibrous cellulose composite resin and a method for producing the same.

Claims (10)

The raw material fibers are defibrated to obtain fibrous cellulose having an average fiber width of 0.1 to 15 μm.
This fibrous cellulose, resin, and polybasic acid are kneaded and treated.
During the kneading treatment, the fibrous cellulose was modified with the polybasic acid to form the fibrous cellulose.
Prior to the kneading, dehydration treatment and drying treatment are performed so that the water content of the fibrous cellulose is 5% or less.
A method for producing a fibrous cellulose composite resin. The compounding mass ratio of the polybasic acid in the solid content is 0.1 to 50%.
The method for producing a fibrous cellulose composite resin according to claim 1. At the time of the kneading treatment, amines were added and
The amount of the amines added is 1 to 200 parts by mass with respect to 100 parts by mass of the fibrous cellulose.
The method for producing a fibrous cellulose composite resin according to claim 1 or 2. It is assumed that the fibrous cellulose obtained by the dehydration treatment and the drying treatment contains a resin powder having an average particle size of 1 to 10,000 μm.
The method for producing a fibrous cellulose composite resin according to any one of claims 1 to 3. The fibrous cellulose obtained by the dehydration treatment and the drying treatment is made into a powder having an average particle size of 1 to 10,000 μm.
The method for producing a fibrous cellulose composite resin according to any one of claims 1 to 4. The fibrous cellulose obtained by the dehydration treatment and the drying treatment is made into a powder having a bulk specific density of 0.01 to 1.5.
The method for producing a fibrous cellulose composite resin according to any one of claims 1 to 5. A multi-screw kneader with two or more shafts is used for the kneading process.
The method for producing a fibrous cellulose composite resin according to any one of claims 1 to 6. The peripheral speed of the screw of the multi-screw kneader having two or more shafts is 0.2 to 200 m / min.
The method for producing a fibrous cellulose composite resin according to any one of claims 1 to 7. The ratio of the screw diameter of the multi-screw kneader having two or more shafts to the length of the kneading portion is 15 to 60.
The method for producing a fibrous cellulose composite resin according to any one of claims 1 to 8. It has an average fiber width of 0.1 to 15 μm, an average fiber length of 0.02 to 3.0 mm, a fibrillation rate of 1.0 to 30.0%, is modified with polybasic acid, and has a crystallinity of 90%. It is a kneaded product of fibrous cellulose and resin as described below.
Solubility parameter of fibrous cellulose and resin (cal / cm ³ ) ^1/2 The difference in (SP value) is 10 to 0.1.
A fibrous cellulose composite resin characterized by this.