JP6941940B2 - Polyparaphenylene terephthalamide fiber composite, polycarbonate resin composite containing it - Google Patents

Description

The present invention relates to a polyparaphenylene terephthalamide fiber complex and a polycarbonate resin composite material containing the polyparaphenylene terephthalamide fiber composite as a constituent element.

Polyparaphenylene terephthalamide (hereinafter, may be referred to as PPTA) fiber is formed into a highly crystallized yarn by applying shear with a mouthpiece after making it into a liquid crystal state using concentrated sulfuric acid as a solvent for dissolving the polymer at the time of spinning. Will be done. It is known that concentrated sulfuric acid, which is a solvent, is produced by washing with water and neutralizing with an alkali immediately after spinning, drying and heat-treating at 200 ° C. or higher, and then winding up as a filament (Patent Document 1). ..

PPTA fiber is a synthetic fiber that has high functionality such as high strength, high elastic modulus, high heat resistance, non-conductivity, and rust resistance, as well as suppleness peculiar to organic fiber and light weight. Due to these characteristics, it is used as a rubber reinforcing material for automobiles, motorcycles, bicycle tires, automobile toothed belts, conveyors, etc., or as a reinforcement or rope for optical fiber cables. Furthermore, it is also applied to bulletproof vests, protective clothing such as work gloves and work clothes that are hard to cut against cutlery, and firefighting clothes that are hard to burn.

However, PPTA fibers are chemically stable and have inferior affinity for materials such as resin and rubber as they are, so some pretreatment may be required.

Generally, as a means of applying reinforcing fibers (for example, aramid fibers, carbon fibers, glass fibers, etc.) to a resin to modify the resin, a dry blend of chopped strands of the reinforcing fibers and a thermoplastic resin is used in an extruder. A method is known in which extruded and reinforced fibers are dispersed in a thermoplastic resin and pelletized, and the pellets are added to the thermoplastic resin to perform desired molding to obtain a molded product. However, since this method cannot increase the blending amount of the reinforcing fibers, there is a problem that it is difficult to obtain desired resin properties.

Further, a method in which a continuous fiber bundle of reinforcing fibers is passed through a molten thermoplastic resin, the reinforcing fiber bundle is coated with a thermoplastic resin by a plutolation method, and then pelletized, or a continuous fiber bundle of reinforcing fibers is heated. There is also a method of immersing in a plastic resin emulsion and then cutting the dried material to pelletize it. According to the former pull lution method, the mechanical properties of the molded product are improved by about 10 to 20% as compared with the conventional product, but further improvement is desired.

The latter method of immersing a continuous fiber bundle in a thermoplastic resin emulsion and drying it has been studied mainly for inorganic fibers such as glass fibers and carbon fibers.
For example, a glass fiber bundle is immersed in an acrylonitrile-styrene copolymer resin emulsion, the adhered resin is dried or dried and melted, and the resin-coated glass fiber bundle is cut to a predetermined length to obtain pellets and heat. A resin composition obtained by extrusion-molding a mixture of a plastic resin is superior in terms of tensile strength, bending strength, elasticity, impact resistance, etc., as compared with a resin composition obtained by the chopped strand method. It is disclosed (Patent Document 2).
Further, a thermoplastic resin emulsion which is a diene-based monomer (butadiene) -styrene copolymer and has a glass transition point of 20 ° C. to 100 ° C. is adhered to a bundle of continuous fibers (glass fibers, carbon fibers), and the glass of the thermoplastic resin is attached. It is disclosed that the resin pellets obtained by cutting a continuous fiber bundle dried and melted at a temperature of a transition point to 300 ° C. to a predetermined length have good dispersibility in a polycarbonate resin (Patent Document 3). ..
Further, a 4-t-butylcyclohexyl methacrylate-glycidyl methacrylate copolymer or a 4-t-butylcyclohexyl-styrene-maleic anhydride copolymer resin emulsion of acrylate is added to a continuous fiber (carbon fiber) together with an epoxysilane coupling agent. ) The molded product adhered to the bundle is cut to a predetermined length, and the cut fiber bundle is kneaded with polypropylene resin to obtain a molded product, which is formed by using pellets to which an epoxy sizing agent is attached. It is disclosed that the tensile breaking strength, bending strength, and icott strength are superior to those of the molded molded product (Patent Document 4).

U.S. Pat. No. 3,767,756 Japanese Unexamined Patent Publication No. 10-330503 Japanese Unexamined Patent Publication No. 2000-167828 Japanese Unexamined Patent Publication No. 2005-146431

However, the adherent resin melting method disclosed in Patent Documents 2 and 3 is excellent in that the amount of resin adhered to the fiber bundle increases, but when the adhesive resin has poor affinity for the fibers, the adherent resin becomes It may fall off from the fiber surface. On the other hand, the resin emulsion adhesion method disclosed in Patent Document 4 requires an auxiliary agent such as a silane coupling agent and also requires presizing treatment of the carbon fiber bundle, so that the treatment step is complicated. ..

By the way, among various thermoplastic resins, polycarbonate resin has excellent impact resistance, has a high glass transition point and a high deflection temperature under load, and therefore has high strength, high elastic modulus, high heat resistance, and non-conformity. By combining with aramid fiber, which has high functionality such as conductivity and rust resistance, suppleness, and light weight, there is a possibility that it can be a highly functional composite material that has never existed in the past.
An object of the present invention has been made in view of the above background, and an object of the present invention is to provide a polyparaphenylene terephthalamide fiber composite having an affinity for a polycarbonate resin, and a polycarbonate resin composite material containing the polyparaphenylene terephthalamide fiber composite as a constituent element. ..

As a result of diligent studies on a polyparaphenylene terephthalamide fiber composite having an affinity for a polycarbonate resin, the present inventors have no history of a water content of less than 15% by mass, and the water content is 15 to 200% by mass. the polyparaphenylene terephthalamide fibers in skeletal adjusted to, by attaching permeate acrylic resins dispersion, found that fiber composite is compatible with the polycarbonate resin obtained, have reached the present invention.
That is, the present invention is as follows.

(1) There is no history that the water content is less than 15% by mass. In the polyparaphenylene terephthalamide fiber skeleton adjusted to a water content of 15 to 200% by mass, (meth) acrylic acid ester or acrylonitrile is unsaturated. An acid-modified acrylic resin dispersion which is a copolymer of a carboxylic acid and another copolymerizable ethylenically unsaturated compound and contains 5 to 50% by mass of the unsaturated carboxylic acid is provided with the water content of the fiber. The polyparaphenylene terephthalamide fiber composite is characterized in that the solid content is 0.1% by mass or more and 10.0% by mass or less with respect to the fiber mass when converted to 0% by mass.
(2) The acid-modified acrylic resin is a 3- to quaternary copolymer, the (meth) acrylic acid ester is methyl (meth) acrylate or ethyl (meth) acrylate, and the unsaturated carboxylic acid is acrylic. The polyparaphenylene terephthalamide fiber composite according to (1) above, which is one or more selected from acid, methacrylic acid, maleic acid and maleic anhydride.
( 3 ) The polyparaphenylene terephthalamide fiber complex according to (1) or (2) above, wherein the average particle size of the resin dispersion is 20 to 300 nm.
( 4 ) A polycarbonate resin composite material comprising the polyparaphenylene terephthalamide fiber composite according to any one of (1) to ( 3) above as a constituent element.

According to the present invention, the adhesiveness to the polycarbonate resin is improved as compared with the polyparaphenylene terephthalamide fiber to which the resin has not adhered and penetrated. Thereby, it is possible to provide a fiber composite useful as a reinforcing fiber such as a polycarbonate resin while maintaining the original high Young's modulus of the polyparaphenylene terephthalamide fiber. This polyparaphenylene terephthalamide fiber complex can be used in a wide range of applications as a composite material.

The polyparaphenylene terephthalamide (PPTA) in the present invention is a polymer obtained by polycondensing terephthalic acid and para-phenylenediamine, but a polymer obtained by copolymerizing a small amount of dicarboxylic acid and diamine can also be used. Alternatively, the molecular weight of the copolymer is usually preferably 20,000 to 25,000.

In ordinary PPTA fibers, PPTA is dissolved in concentrated sulfuric acid, the viscous solution is extruded from a spinneret, spun into air or water to form filaments, and then neutralized with an aqueous sodium hydroxide solution. Finally, it is obtained by drying and heat-treating at 120 to 500 ° C.

In the present invention, the PPTA fiber adjusted to have a water content of 15 to 200% by mass can be obtained, for example, as follows. That is, PPTA is dissolved in concentrated sulfuric acid to obtain a viscous solution of 18 to 20% by mass, which is discharged from the spinneret, spun in the air for a short time, and then spun into water (at this time, the spinneret). The shear rate at the time of discharge ^{is preferably 25,000 to 50,000 sec -1} ), and after undergoing a water-washing neutralization treatment, the obtained raw yarn is dried at 100 to 160 ° C., preferably for 5 to 20 seconds. do. If the water content is less than 15% by mass, it becomes difficult to uniformly permeate the resin dispersion into the fiber skeleton, while if the water content exceeds 200% by mass, the permeated resin dispersion is before the winding process. When it comes into contact with a guide or the like, it may fall off together with moisture, and the fiber winding process becomes difficult. The water content of the PPTA fiber is preferably 15 to 100% by mass, more preferably 20 to 50, from the viewpoints of the permeability of the resin dispersion into the PPTA fiber skeleton, the ease of adjusting the water content of the PPTA fiber, the production efficiency, and the like. It is by mass, particularly preferably 35 to 50% by mass.

The PPTA fiber composite of the present invention maintains a state in which the crystal size of the PPTA fiber is less than 50 angstroms and the moisture content is 15 to 200% by weight while changing the heat treatment conditions at a temperature of 100 to 160 ° C. It is obtained by making PPTA fibers that can be maintained and adhering and permeating the resin dispersion into the PPTA fiber skeleton. When the crystal size of the PPTA fiber is 50 angstroms or more, it becomes difficult to allow the resin dispersion to penetrate into the fiber skeleton. Here, the term “adhesive permeation” means that the resin dispersion that adheres to the surface of the PPTA fiber when the resin dispersion is permeated into the PPTA fiber skeleton is also included.

Further, it is desirable that the PPTA fiber does not have a history of being dried to a moisture content of less than 15% by mass after spinning. This is because by using PPTA fibers whose water content is always adjusted to 15% by mass or more, it is possible to maintain a state in which the resin dispersion easily permeates.

The treatment step is that the resin dispersion permeated into the PPTA fiber skeleton adjusted to have a water content of 15 to 200% by mass does not use a silane coupling agent such as aminopropyltrimethoxysilane or aminopropyltriethoxysilane in combination. Although it is preferable from the viewpoint of preventing the complexity of the above and the deterioration of the mechanical properties of the molded product, it may be used in combination if desired. When the resin dispersion contains a silane coupling agent, it may hinder the affinity with the resin in the dispersion by preferentially reacting with the functional groups slightly present in the PPTA fiber skeleton.

The PPTA fiber composite to which the resin dispersion is adhered and permeated is, for example, wound on a bobbin in a winding step, then unwound from the bobbin, heat-treated to remove water, and the water content is reduced to less than 15% by mass. , The PPTA fiber composite of the present invention can be obtained.

The resin dispersion adheres and permeates 0.1 to 10.0% by mass, more preferably 0.2 to 5.0% by mass, as a solid content with respect to the fiber mass in which the water content of the PPTA fiber is converted to 0%. Is good. If the amount of adhesion permeation is small, the effect of imparting adhesiveness may not be sufficiently exhibited.

In the present invention, the acrylic or styrene resin dispersion is used as a resin dispersion that does not have a history of having a water content of less than 15% by mass and is allowed to permeate into the PPTA fiber skeleton adjusted to a water content of 15 to 200% by mass. Used.

(Acrylic resin dispersion)
Examples of the acrylic resin constituting the acrylic resin dispersion include (meth) acrylic acid ester-based copolymers and acrylonitrile-based copolymers. In the present invention, the (meth) acrylic acid ester means an acrylic acid ester or a methacrylic acid ester.

The (meth) acrylic acid ester-based copolymer is a copolymer of a (meth) acrylic acid ester and another copolymerizable ethylenically unsaturated compound, and the acrylonitrile-based copolymer is an acrylonitrile and another. It is a copolymer with a copolymerizable ethylenically unsaturated compound.

As the acrylic resin, 2 to 4 of a (meth) acrylic acid ester or acrylonitrile and another copolymerizable ethylenically unsaturated compound from the viewpoint of permeability into the PPTA fiber skeleton and adhesion to a polycarbonate resin. The original copolymer is preferable. The mass average molecular weight (Mw) is preferably about 2,000 to 100,000.

Examples of the (meth) acrylic acid ester include methyl (meth) acrylic acid, ethyl (meth) acrylic acid, n-propyl (meth) acrylic acid, iso-propyl (meth) acrylic acid, and n-butyl (meth) acrylic acid. , (Meta) acrylate sec-butyl, (meth) acrylate iso-butyl, (meth) acrylate tert-butyl, (meth) acrylate n-pentyl, (meth) acrylate -2-ethylhexyl, etc. (Meta) acrylic acid esters having a hydrocarbon group; cyclopentyl (meth) acrylic acid, cyclohexyl (meth) acrylic acid, cycloheptyl (meth) acrylic acid, cyclooctyl (meth) acrylic acid, isobornyl (meth) acrylic acid, etc. (Meta) acrylic acid esters having an alicyclic hydrocarbon group; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, (meth) Examples thereof include (meth) acrylic acid esters having a hydroxyalkyl group such as 3-hydroxybutyl acrylate and 4-hydroxybutyl (meth) acrylate. These compounds may be used alone or in combination of two or more. Among these, (meth) acrylates having an aliphatic hydrocarbon group are preferable from the viewpoint of availability and permeability into the PPTA fiber skeleton, and methyl (meth) acrylate and ethyl (meth) acrylate. Is more preferable.

Other copolymerizable ethylenically unsaturated compounds include, for example, acrylic acid, methacrylic acid, crotonic acid, isocrotonic acid, maleic acid, fumaric acid, itaconic acid, maleic anhydride, itaconic anhydride, citraconic anhydride, cyclohexene. Unsaturated carboxylic acids such as dicarboxylic acids; vinyl carboxylic acid esters such as vinyl acetate and vinyl propionate; nitrogen-containing compounds such as (meth) acrylamide and (meth) acrylonitrile; epoxy group-containing compounds such as glycidyl (meth) acrylate; Aromatic vinyl compounds such as styrene, p-methylstyrene, o-methylstyrene, m-methylstyrene, α-methylstyrene, vinyltoluene; unsaturated carboxylic acid alkyl esters such as benzyl (meth) acrylate; aminoethyl (meth) Unsaturated carboxylic acid aminoalkyl esters such as acrylates; unsaturated carboxylic acid glycidyl esters such as glycidyl (meth) acrylates; nitrogen-containing compounds such as vinylpyridine and (meth) acrylamide; aliphatic conjugates such as 1,3-butadiene and isoprene. Jien; etc. These compounds may be used alone or in combination of two or more.

Among these compounds, unsaturated carboxylic acids, aromatic vinyl compounds or epoxy group-containing compounds are preferable, and unsaturated carboxylic acids are particularly preferable, from the viewpoint of availability and stability of acrylic resin dispersion. The unsaturated carboxylic acid can be used alone or in any combination of two or more.

By copolymerizing an unsaturated carboxylic acid, an acid-modified acrylic resin having a carboxyl group can be obtained. Among the unsaturated carboxylic acids, acrylic acid, methacrylic acid, maleic acid, etc. Maleic anhydride is preferred. When maleic anhydride is used as another monomer, the ratio of maleic anhydride can be increased by further copolymerizing an aromatic vinyl compound such as styrene, and the adhesiveness to the polycarbonate resin can be improved. Can be done.

In acid-modified acrylic resins, copolymerizable ethylenically unsaturated substances other than (meth) acrylic acid esters and unsaturated carboxylic acids in all the monomers constituting the (meth) acrylic acid ester-based copolymers. The ratio of the compounds is preferably 50 to 99% by mass, more preferably 50 to 95% by mass in total, from the viewpoint of permeability into the PPTA fiber skeleton and stability of the resin dispersion. The ratio of the unsaturated carboxylic acid is preferably 1 to 50% by mass, more preferably 5 to 50% by mass. The ratio of the unsaturated carboxylic acid is preferably determined so that the acid value of the acid-modified acrylic resin is 0.1 to 500.
The acid value is the amount of potassium hydroxide required to neutralize the carboxyl group in the sample expressed in mg with respect to 1.0 g of the sample, and is a scale indicating the content of the carboxyl group in the sample. be

(Styrene resin dispersion)
As the styrene resin constituting the styrene resin dispersion, an acid-modified styrene resin having a carboxyl group is preferably used. Examples of the styrene-based resin include copolymers of aromatic vinyl compounds and other copolymerizable unsaturated compounds.

As the styrene resin, a copolymer of styrene and a copolymerizable unsaturated compound, which is a 2 to 4 element copolymer and has an acid value of 0.1 to 500, is preferable from the viewpoint of adhesiveness to the polycarbonate resin. .. The mass average molecular weight (Mw) is preferably about 2,000 to 100,000.

Examples of the aromatic vinyl compound include styrene, p-methylstyrene, o-methylstyrene, m-methylstyrene, α-methylstyrene, vinyltoluene and the like.
Other copolymerizable unsaturated compounds include, for example, dienes such as butadiene, isoprene, chloroprene; acrylic acid, methacrylic acid, crotonic acid, isocrotonic acid, maleic acid, fumaric acid, itaconic acid, maleic anhydride, anhydrous. Unsaturated carboxylic acids such as itaconic acid, citraconic anhydride, cyclohexendicarboxylic acid; carboxylic acid vinyl esters such as vinyl acetate and vinyl propionate; nitrogen-containing compounds such as vinylpyridine, (meth) acrylamide, (meth) acrylonitrile; etc. Can be mentioned. These compounds may be used alone or in combination of two or more. Among these, dienes, unsaturated carboxylic acids or nitrogen-containing compounds are preferable from the viewpoint of availability and stability of resin dispersion, and the unsaturated carboxylic acids include acrylic acid, methacrylic acid, maleic acid and maleic anhydride. Acids are preferred.

The ratio of the aromatic vinyl compound in the copolymer of the aromatic vinyl compound and the other copolymerizable unsaturated compound is 50 to 50 in terms of permeability into the PPTA fiber skeleton and stability of the resin dispersion. It is preferably 99% by mass, more preferably 50 to 95% by mass. The ratio of other copolymerizable unsaturated compounds is preferably 1 to 50% by mass, more preferably 5 to 50% by mass.

As the resin dispersion, those obtained by a known polymerization method such as solution polymerization, suspension polymerization, emulsion polymerization and the like can be used. Considering the permeation of the resin dispersion into the PPTA fiber skeleton adjusted to have a water content of 15 to 200% by mass, the polymer obtained by the emulsification polymerization method or the polymer obtained by another polymerization method is forcibly emulsified. Therefore, those dispersed in water, an aqueous solvent, or a mixed solvent thereof are preferably used.

Examples of the aqueous solvent include esters, aliphatic alcohols, (poly) alkylene glycol ethers, ketones and the like, and a mixed solvent of two or more kinds may be used. Further, an organic solvent other than these may be mixed.

In the present invention, the resin concentration in the resin dispersion is not particularly limited, but a dispersion having a resin concentration of about 10 to 50% by mass is preferably used. The resin particle size is preferably small, and more preferably has an average particle size (according to electron microscopy) of about 20 to 300 nm. The pH of the resin dispersion is preferably in the range of 6 to 10.

In the present invention, when the resin dispersion is permeated into the PPTA fiber skeleton adjusted to have a water content of 15 to 200% by mass, it may be used by being contained in an oil agent, or may be used in a separate step from the oil agent. Examples of the oil agent include general oil agents used for PPTA fibers, for example, low molecular weight fatty acid esters, polyethers, mineral oils and the like having 18 or less carbon atoms. When the resin is contained in the oil agent, it is preferably contained in the oil agent in an amount of about 20 to 60% by mass, more preferably 30 to 50% by mass.

The method of applying the resin dispersion and the oil agent containing the resin dispersion to the PPTA fiber is not particularly limited, and any conventionally known method may be adopted. , It is applied to PPTA fiber by a method such as a guide lubrication method using a measuring pump.

The PPTA fiber composite to which the resin dispersion is adhered and permeated is continuously or once wound around the bobbin in the winding step, and then the wound PPTA fiber composite is unwound from the bobbin and heat-treated. The water content can be less than 15% by mass, more preferably less than 10% by mass. The heat treatment conditions are not particularly limited. For example, when the heat treatment is performed at 80 to 300 ° C., preferably 100 to 250 ° C., the moisture content can be reduced to less than 15% by mass. By this heat treatment, the crystal size of PPTA is increased, and the resin can be fixed in the PPTA fiber skeleton by narrowing the intercrystal gap.

Most of the surface functional groups of PPTA fibers are amide groups, but amine groups and carboxyl groups are present due to hydrolysis of the amide groups, although the amount is small. When an acid-modified resin dispersion in which unsaturated carboxylic acids are introduced by copolymerization or the like is permeated into a PPTA fiber skeleton whose water content is adjusted to 15 to 200% by mass, a reactive functional group is introduced into the PPTA fiber skeleton. By doing so, it is possible to form a state in which it easily reacts with the surface functional group of the PPTA fiber. The reaction may be carried out under unheated and / or heated conditions. The reaction rate varies depending on the type of resin to be introduced and the drying conditions after introduction, but usually, it often does not react under non-heated conditions, and it is presumed that heating facilitates the reaction.

The PPTA fiber composite obtained in the present invention is suitably used as a composite material with a polycarbonate resin. Other than that, it can be widely applied to rubber materials and composite materials with resin materials such as polypropylene resins other than polycarbonate resins and polyamide resins.

The form of the composite material is not particularly limited as long as it is a composite of a PPTA fiber composite and a resin or rubber, and may be in the form of pellets, sheets, or the like. Further, the PPTA fiber composite can be applied to a composite material in various forms such as a cut fiber, a fiber bundle, a woven fabric, a knitted fabric, a twisted yarn, and a processed yarn.

When used for rubber reinforcement, a method of dipping the PPTA fiber composite of the present invention with a known resorcin formalin latex (RFL) can be mentioned. For example, 100 parts by mass of rubber latex is applied to the PPTA fiber composite. A mixture containing 2 to 20 parts by mass of the initial condensate of resorcin-formaldehyde is subjected to an RFL treatment solution containing about 5 to 25% by mass of solid content, and then heat-treated at 100 to 260 ° C.

Rubber latex includes vinylpyridine-styrene-butadiene copolymer rubber latex, styrene-butadiene rubber latex, acrylonitrile-butadiene rubber latex, chloroprene rubber latex, chlorosulfonated polyethylene rubber latex, acrylate rubber latex and natural rubber. Examples thereof include latex, and examples of the resorcin-formaldehyde initial condensate include a novolac-type condensate obtained by condensing resorcin-formaldehyde under an acid catalyst or an alkali catalyst. The treatment liquid may be mixed with one or more compounds selected from a blocked polyisocyanate compound, an ethyleneimine compound, a reaction product of polyisocyanate and ethyleneimine, and the like.

Since the PPTA fiber complex of the present invention has the resin dispersion permeated into the PPTA fiber skeleton, it has good adhesion of the RFL treatment liquid and is unlikely to cause a strong decrease in the cord when the RFL high temperature treatment is performed. There are advantages.

The floc-shaped short fiber composite obtained by cutting the PPTA fiber composite that has been immersed with RFL to 0.1 to 5 mm can be used as a reinforcing material for rubber belts and to 0.1 to 5 mm without RFL treatment. The cut flock-shaped short fiber composite can be used as an additive for resin or the like.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples. In addition, each measured value in an Example followed the following method.

(1) Moisture content (mass%)
The mass of about 5 g of the sample is measured, heat-treated at 105 ° C. for 1 hour, left at 24 ° C. and 55% RH for 5 minutes, and then the mass is measured again. The moisture content used here is the dry base moisture content obtained by [mass before drying-mass after drying] / [mass after drying] × 100.

(2) Amount of resin adhered to fibers (mass%)
The fibers before the resin dispersion treatment are sampled to a predetermined length, and the mass after the treatment at 105 ° C. for 4 hours is measured. Next, the fibers after the resin dispersion treatment are sampled at the same length, and the mass after the same treatment at 105 ° C. for 4 hours is measured. The amount of resin adhered to the fibers used here is obtained by [mass after treatment-mass before treatment] x 100 / [mass before treatment].

(3) Peeling load (N)
Using a tensile tester, a resin sheet with long fibers that do not have about 20 mm from the end attached is installed on the resin surface on a jig designed so that the plate-shaped resin sample moves smoothly in the horizontal direction. Then, the non-sticked end was sandwiched between the chucks that move in the vertical direction, and the load when the chuck was moved upward was measured and used as the peeling load.

(Example 1)
1 kg of PPTA (molecular weight of about 20,000) obtained by a usual method is dissolved in 4 kg of concentrated sulfuric acid, and discharged ^{from a mouthpiece having 1,000 holes with a diameter of 0.1 mm so as to have a shear rate of 30,000 sec -1.} Then, after spinning in water at 4 ° C., neutralization treatment was performed with a 10% by mass sodium hydroxide aqueous solution under the conditions of 10 ° C. × 15 seconds, and then low-temperature drying at 110 ° C. × 15 seconds was performed to obtain a water content. It was adjusted to 35% by mass of PPTA fiber (fineness of 1,670 dtex when converted to 0% by mass of water content). Furthermore, this PPTA fiber is a quaternary copolymer obtained by copolymerizing acrylic acid, maleic acid, methyl acrylate and styrene (acrylic acid / maleic acid / methyl acrylate / styrene = 0.1 / 35.0 / 48. After passing through a dip bath made of 9 / 16.0 (mass ratio) resin dispersion, squeeze it with a roll, adjust the amount of adhesion, and dry it at 105 ° C for 4 hours to convert it to 0% by mass. A PPTA fiber composite was produced in which 2.4% by mass (resin equivalent) of resin was impregnated into the fibers at the time of the above.

2.08 times / inch single twist was added to the obtained PPTA fiber composite.
After aligning the seven PPTA fiber composites so that the length is 265 mm or more at 1 mm intervals in the vertical direction, the portion to be the fiber end is determined, and the length is 20 mm from the end in the fiber alignment direction. A polycarbonate resin sheet having a thickness of 4 mm was placed on the resin sheet, and the resin was melted by treating the resin at 250 ° C. under a load of 10 MPa for 15 minutes using a 3.8 mm spacer in a heat press molding machine. Under the conditions, the mold was cooled and solidified at 50 ° C. to obtain a sheet in which the PPTA fiber composite was attached on a 3.8 mm thick polycarbonate resin sheet. The peeling load of the PPTA fiber composite in this sheet test piece was 34 N.

(Example 2)
On the polycarbonate resin sheet in the same manner as in Example 1 except that the resin permeation amount in Example 1 is 4.7% by mass (resin equivalent) with respect to the fiber when the moisture content is converted to 0% by mass. A sheet to which the PPTA fiber composite was attached was obtained. The peeling load of the PPTA fiber composite in this sheet test piece was 41 N.

(Comparative Example 1)
6. The moisture content without resin adhesion was determined by the same method as in Example 1 except that the PPTA fiber before the treatment having a moisture content of 35% by mass obtained in Example 1 was dried without passing the dip liquid. 9% by mass PPTA fiber was obtained. Using this PPTA fiber, a sheet in which the PPTA fiber was attached on a polycarbonate resin sheet was obtained by the method described in Example 1. The peeling load of the PPTA fiber in this sheet test piece was 17N.

(Comparative Example 2)
Instead of the resin dispersion in Example 1, the same method as in Example 1 was used except that aminopropyltrimethoxysilane was permeated into the fibers in terms of water content of 0% by mass by 0.63% by mass. , A sheet in which a PTA fiber composite was attached on a polycarbonate resin sheet was obtained. The peeling load of the PPTA fiber in this sheet test piece was 18N.

From the results in Table 1, the PPTA fiber composites of Examples 1 and 2 to which the quaternary copolymer resin dispersion was attached were PPTA fibers to which the quaternary copolymer resin dispersion was not attached (Comparative Example 1). It can be seen that the adhesiveness to the polycarbonate resin is better than that of the above.

The polyparaphenylene terephthalamide fiber composite of the present invention is useful for various industrial materials as a polycarbonate resin composite material and the like.

Claims (4)

In a polyparaphenylene terephthalamide fiber skeleton adjusted to a water content of 15 to 200% by mass, which has no history of a water content of less than 15% by mass, (meth) acrylic acid ester or acrylonitrile and an unsaturated carboxylic acid , An acid-modified acrylic resin dispersion containing 5 to 50% by mass of an unsaturated carboxylic acid, which is a copolymer with another copolymerizable ethylenically unsaturated compound, and has a water content of 0 mass of the fiber. A polyparaphenylene terephthalamide fiber composite characterized in that a solid content of 0.1% by mass or more and 10.0% by mass or less is adhered and permeated with respect to the fiber mass when converted to%. The acid-modified acrylic resin is a 3- to quaternary copolymer, the (meth) acrylic acid ester is methyl (meth) acrylate or ethyl (meth) acrylate, and the unsaturated carboxylic acid is acrylic acid or methacrylic acid. The polyparaphenylene terephthalamide fiber composite according to claim 1, which is one or more selected from acid, maleic acid and maleic anhydride. The polyparaphenylene terephthalamide fiber complex according to claim 1 or 2 , wherein the average particle size of the resin dispersion is 20 to 300 nm. A polycarbonate resin composite material comprising the polyparaphenylene terephthalamide fiber composite according to any one of claims 1 to 3 as a constituent element.