JP3950410B2 - Fiber, fiber assembly, fiber assembly molding - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fiber assembly such as a fiber composed of a crystalline thermoplastic resin and an amorphous thermoplastic resin, a web composed of the fiber, a knitted fabric, and the like, and a fiber assembly molded product obtained by molding the fiber assembly into a predetermined shape. Is.
[0002]
[Prior art]
Conventionally, fibers made of thermoplastic resins such as polyamide, polypropylene and polyester have been used in various applications such as interior materials and building materials for automobiles such as ceiling materials and carpets. There are also provided fibers made of a polymer alloy of two or more thermoplastic resins, for example, a fiber made of a polymer alloy of polyamide and polypropylene (for example, see Patent Document 1).
[0003]
[Patent Document 1]
Japanese Patent Laid-Open No. 3-51314
[Problems to be solved by the invention]
Thermoplastic resins such as polyamide and polypropylene are crystalline. When a fiber assembly such as a knitted fabric or web made of this kind of thermoplastic resin is heated and pressed to form a molded product, the dimensional stability of the molded product is improved. There was a problem that the nature was bad.
In addition, when a fiber assembly obtained from polyamide and polypropylene polymer alloy fibers is hot-pressed into a molded product, the molded product has generally good dimensional stability, but the molded product has poor shapeability. was there. Therefore, when a molded product having a complicated shape such as unevenness is produced from this type of fiber assembly, it is necessary to always impregnate the fiber assembly with a thermosetting resin such as a phenol resin. It was.
[0005]
[Means for Solving the Problems]
In the present invention, as means for solving the above problems, 100 parts by mass of a mixture in which polyamide as a crystalline thermoplastic resin and polycarbonate as an amorphous thermoplastic resin are mixed in a ratio of 1:99 to 99: 1 by mass. In contrast, a fiber (1) obtained by melt spinning a polymer alloy to which 0.01 to 60 parts by mass of a copolymer of maleic anhydride and allyl ether is added as a compatibilizing agent , or a crystalline thermoplastic resin As a compatibilizer, a partially hydrogenated alkenyl aromatic compound is used as a compatibilizer with respect to 100 parts by mass of a mixture of polypropylene as a non-crystalline thermoplastic resin and styrene-modified polyphenylene ether as an amorphous thermoplastic resin in a ratio of 1:99 to 99: 1 by mass. - fibers a polymer alloy prepared by adding conjugated diene block copolymer 0.01 to 60 parts by mass obtained by melt spinning (1), or As a compatibilizing agent for 100 parts by mass of a mixture in which polyamide as a crystalline thermoplastic resin and high impact polystyrene-modified polyphenylene ether as an amorphous thermoplastic resin are mixed in a ratio of 1:99 to 99: 1 by mass. Provided is a fiber (1) obtained by melt spinning a polymer alloy to which 0.01 to 60 parts by mass of an epoxy group-containing unsaturated monomer is added .
Crystalline thermoplastic resin used in the present invention are polypropylene, a port Riami de, non-crystalline thermoplastic resin is denatured polyphenylene ether.
The present invention also provides a fiber assembly containing the fiber (1).
Examples of the fiber aggregate include a fiber aggregate in which vegetable fibers are mixed, a web or a web laminate, a nonwoven fabric in which the web or web laminate is entangled by needle punching, and fibers are bound by a synthetic resin binder. Non-woven fabrics and fiber knitted fabrics are included.
Furthermore, the present invention provides a fiber維集coalescence molded article was molded into a predetermined shape by heat-pressing the fiber aggregate.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail.
〔fiber〕
The fiber (1) of the present invention comprises a polymer alloy of a crystalline thermoplastic resin and an amorphous thermoplastic resin.
Binding-crystalline thermoplastic resins that are used in the polymer alloy, polypropylene (PP), Po Li caprolactam (nylon 6), polyhexamethylene adipamide (nylon 66), polyhexamethylene sebacamide (nylon 610), Poriundeka 1 lactam (nylon 11), Poridodeka 1 lactam (nylon 12) Ru polyamide (PA) der such.
[0007]
The non-crystalline heat-friendly thermoplastic resins used in the polymer alloy, for example, port polycarbonate (PC), modified polyphenylene ether (modified PPE) Ru der.
[0008]
The modified PPE refers to styrene, α-methyl styrene, α-ethyl styrene, α-methyl vinyl toluene, α-methyl dialkyl styrene, o, m or p-vinyl toluene, o-ethyl styrene, p-ethyl. Styrene, 2,4-dimethylstyrene, o-chlorostyrene, p-chlorostyrene, o-bromostyrene, 2,4-dichlorostyrene, 2-chloro-4-methylstyrene, 2,6-dichlorostyrene, vinylnaphthalene, Graft polymerization of styrene monomers such as vinyl anthracene, or polymer alloy by mixing styrene resins such as polystyrene, styrene-acrylonitrile resin, acrylonitrile-butadiene-styrene resin (ABS), high impact polystyrene (HIPS), etc. It is.
[0009]
The polymer alloy of the present invention may contain a rubber-like substance if desired. Examples of the rubbery substance include acrylic rubber, butyl rubber, silicon rubber, urethane rubber, fluoride rubber, polysulfide rubber, graft rubber, butadiene rubber, isoprene rubber, chloroprene rubber, polyisobutylene rubber, polybutene rubber, isobutene. Rubber-isoprene rubber, acrylate-butadiene rubber, styrene-butadiene rubber, acrylonitrile-butadiene rubber, pyridine-butadiene rubber, styrene-isoprene rubber, acrylonitrile-chloroprene rubber, rubber such as styrene-chloroprene rubber, natural rubber, styrene-butadiene- Styrene block copolymer (SBS), styrene-isoprene-styrene block copolymer (SIS), α-methylstyrene-butadiene-α-methylstyrene block copolymer (α-MeS-B -MeS), α-methylstyrene-isoprene-α-methylstyrene block copolymer, styrene-hydrogenated polyolefin-styrene block copolymer (SEBS, SEPS) and other styrene elastomers, polyolefin elastomers, polyurethane elastomers, Examples include polyester elastomers and polyamide elastomers. These rubber-like substances are used alone or in combination of two or more.
[0010]
More polymer alloy consisting of crystalline thermoplastic resin and the non-crystalline thermoplastic resin, a compatibilizer for the purpose of improving the compatibility of each component is Ru added.
Since the compatibilizing agent is composed of a compound having affinity for each component of the polymer alloy, the mixing state of each component in the polymer alloy is made uniform through each component. Therefore, the characteristics of each component are effectively exhibited, and the material has extremely good dimensional stability, moldability, and formability.
[0011]
(Delete)
[0012]
The compatibilizer used in the port Rimaaroi of the present invention, in the case of PA-PC, a copolymer of maleic acid with allyl ether anhydride is used, in the case of PP- modified PPE, partially hydrogenated alkenyl aromatic A group compound-conjugated diene block copolymer is used, and in the case of PA-modified PPE, an epoxy group-containing unsaturated monomer is used.
[0013]
(Delete)
[0014]
In the polymer alloy of the present invention, the crystalline thermoplastic resin and the amorphous thermoplastic resin are usually mixed at a ratio of 1:99 to 99: 1 by mass, and the rubber-like substance is usually added to 100 parts by mass of the polymer alloy. On the other hand, 0.5-100 mass parts and a compatibilizing agent are usually added 0.01-60 mass parts.
[0015]
The what is marketed as a polymer alloy for use in the present invention, for example, a polymer alloy of P A and the PPE, NORYL GTX (manufactured by GE Plastics Japan Ltd.), a polymer alloy of P PS and PPE are Iupiace SX (SX1000, SXG1040) and the like.
[0016]
Further, the polymer alloy used in the fiber (1) of the present invention may optionally include calcium carbonate, magnesium carbonate, barium sulfate, calcium sulfate, calcium sulfite, calcium phosphate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, oxidized Magnesium, titanium oxide, iron oxide, zinc oxide, alumina, silica, diatomaceous earth, dolomite, gypsum, talc, clay, asbestos, mica, calcium silicate, bentonite, white carbon, carbon black, iron powder, aluminum powder, glass powder, Stone powder, synthetic resin powder, blast furnace slag, fly ash, cement, zirconia powder, linter, linen, sisal, wood powder, wheat flour, walnut powder, den powder, coconut powder, rice flour, filler, polyamide fiber, polyester fiber, acrylic Fiber, viscose Fibers such as organic synthetic fibers such as fibers, acetate fibers, vinyl chloride fibers, vinylidene chloride fibers, and vinylon fibers may be added.
The filler or the like may be usually added in an amount of about 0.01 to 200% by mass with respect to the polymer alloy.
[0017]
Furthermore, the polymer alloy of the present invention includes pigments, dyes, plasticizers such as DOP and DBP, antioxidants, antistatic agents, crystallization accelerators, flame retardants, flame retardants, insecticides, antiseptics, waxes. Further, a lubricant, an anti-aging agent, an ultraviolet absorber, a foaming agent and the like may be added. These components may be added singly or in combination of two or more.
[0018]
The crystalline thermoplastic resin and non-crystalline thermoplastic resin used in the polymer alloy of the present invention may be a crystalline thermoplastic resin or non-crystalline thermoplastic resin obtained from a waste material of a thermoplastic resin molded article. In addition, trimming waste generated during injection molding, vacuum forming, melt spinning, etc. of thermoplastic resin, resin waste adhering to the molding machine, and the like may be used for the polymer alloy of the present invention.
In these cases, the waste and waste material used may be a waste made only of a crystalline thermoplastic resin or a non-crystalline thermoplastic resin, or a crystalline thermoplastic resin and a non-crystalline thermoplastic resin. It may be a waste made of a polymer alloy.
[0019]
(Fiber manufacturing method)
The fiber (1) made of the polymer alloy of the present invention is produced by a melt spinning method, which is a method for producing an ordinary thermoplastic resin fiber.
For example, a PA and PPE polymer alloy pelletized by a twin-screw kneader is spun from a spout of φ0.25 × 12 Hole at 300 ° C. and unwound by winding at a spinning speed of 100 m / min. Get.
The obtained undrawn yarn is drawn 3 times with a roll type drawing machine to obtain a drawn yarn.
[0020]
[Fiber assembly]
The fiber assembly of the present invention refers to a knitted fabric, a web, a nonwoven fabric, a felt, a mat, and a laminate (web laminate) produced using the fiber (1) comprising the polymer alloy of the present invention described above. It is.
In the fiber assembly of the present invention, fibers composed of only one type of polymer alloy may be used, or fibers of two or more types of polymer alloy may be used.
Along with the polymer alloy fibers (1), for example, polyester fibers, polyethylene fibers, polypropylene fibers, polyamide fibers, acrylic fibers, urethane fibers, polyvinyl chloride fibers, polyvinylidene chloride fibers, synthetic fibers such as acetate fibers, pulp, Dismantle scraps of vegetable fiber such as cotton, palm fiber, hemp fiber, bamboo fiber, kenaf fiber, inorganic fiber such as glass fiber, carbon fiber, ceramic fiber, asbestos fiber, or textile products using these fibers It is also possible to use a mixed fiber assembly using one type or two or more types of recycled fibers.
[0021]
When the fiber assembly of the present invention is a nonwoven fabric or felt, the fibers are usually carded or dispersed on a base material to form a mat, and then the fibers are bound or entangled. The web and mat may be laminated in the same kind or in different layers. In this case, the fibers are bound by a synthetic resin binder, bound by heating and melting, or entangled by needle punching.
Examples of the synthetic resin binder include polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyvinyl acetate, fluororesin, thermoplastic acrylic resin, thermoplasticity Polyester resins, thermoplastic polyamideimide resins, acrylonitrile-butadiene copolymers, styrene-butadiene copolymers, thermoplastic resins such as acrylonitrile-styrene-butadiene copolymers, urethane resins, melamine resins, urea resins, thermosetting acrylics Thermosetting resins such as resins, phenolic resins, epoxy resins and thermosetting polyesters are used, and these synthetic resin binders are usually used in the form of solutions, emulsions or dispersions.
[0022]
The fiber assembly may be impregnated with a synthetic resin, and as the synthetic resin,
The same resin as that used as the synthetic resin binder is used, and the synthetic resin binder is usually impregnated into the fiber assembly in the form of a solution, an emulsion or a dispersion. In addition, although adhesiveness is provided to a fiber assembly by this synthetic resin, reinforcement property and moldability are also provided by this synthetic resin.
[0023]
The solution, emulsion or dispersion further includes water-soluble polymers such as polyvinyl alcohol, sodium alginate, starch, starch derivatives, glue, gelatin, blood powder, methylcellulose, carboxymethylcellulose, polyacrylate, polyacrylamide, and natural gum. Kinds: calcium carbonate, magnesium carbonate, barium sulfate, calcium sulfate. Calcium sulfite, calcium phosphate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, magnesium oxide, titanium oxide, iron oxide, zinc oxide, alumina, silica, diatomaceous earth, dolomite, gypsum, talc, clay, asbestos, mica, calcium silicate , Bentonite, white carbon, carbon black, iron powder, aluminum powder, glass powder, stone powder, synthetic resin powder, blast furnace slag, fly ash, cement, zirconia powder, wood powder, wheat flour, walnut powder, den powder, coconut powder, rice flour Surfactants; higher fatty acids such as stearic acid and palmitic acid, higher alcohols such as palmitic alcohol and stearyl alcohol; esters of fatty acids such as butyl stearate and glycerol monostearate; fatty acid amides; Natural waxes such as cox, synthetic waxes; pigments, dyes, flame retardants, flame retardants, insecticides, antiseptics, anti-aging agents, UV absorbers, fluorescent dyes, surfactants, foaming agents, oil repellents, etc. It may be added.
[0024]
When the fibers are bound by heat fusion, low melting point fibers having a melting point of 200 ° C. or lower and low melting point resin powder may be mixed with the fibers. Examples of such low melting point fibers include polyethylene fiber, polypropylene fiber, low melting point polyester fiber, low melting point polyamide fiber, and low melting point resin powders such as polyethylene powder, low melting point polyester resin powder, and low melting point polyamide powder. .
In the case of heat fusion, the web or mat may be heated as it is to fuse the fibers, or the web or mat may be needle punched and then heated to fuse the fibers.
[0025]
The fiber assembly of the present invention includes polyolefin such as polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, vinyl chloride resin, (meth) acrylic resin, vinylidene chloride resin, styrene Resin, vinyl propionate resin, styrene-butadiene copolymer, polyester resin or other thermoplastic plastic sheet or thermoplastic foam sheet, polyethylene film, low melting point polyamide film, low melting point polyester film, etc. A hot melt film or a reinforcing fiber layer made of the above natural fiber or inorganic fiber may be laminated.
[0026]
In addition, the fiber aggregate includes polyolefin resins such as polyethylene, polypropylene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, and modified products thereof, polyvinyl chloride, polyurethane, polyester, polyester polymer. A hot melt adhesive made of polyamide, polyamide copolymer, cellulose derivative, polyvinyl ether, vinyl block copolymer, butyral, phenol resin, epoxy resin or the like may be added.
[0027]
Further, an adsorbent for trapping volatile substances such as formaldehyde and amine may be mixed or applied to the fiber assembly. Examples of the adsorbent include urea, ethylene urea, propylene urea, 5-hydroxypropylene urea, 5-methoxypropylene urea, 5-methylpropylene urea, 4,5-dimethoxyethylene urea, melamine, or an initial condensate thereof. Compounds, polyhydric phenols such as monohydric phenol, resorcin, and alkyl resorcin, or initial condensates thereof (including resole phenol resin and novolac phenol resin), dicyandiamide, parabanic acid, sodium sulfite, ammonium cobalt, 2,4- Dinitrophenylhydrazine (DNPH), tannins, catechins, flavonoids (flavones, flavonols, dihydroflavonols, isoflavones, flavanones, chalcones, anthocyanidins, etc.), acetylacetone, chitosan Activated carbon, some charcoal, coconut shell, wood flour, bark, the proteins and the like.
[0028]
The fiber assembly of the present invention is excellent in moldability, and a molded product obtained from the fiber assembly is excellent in dimensional stability.
[0029]
[Fiber assembly molded product]
The fiber assembly molded product of the present invention (hereinafter, “molded product”) is a molded product obtained by molding the fiber assembly. In the forming process, a known method such as vacuum and / or pressure forming is applied to a fiber assembly in which a hot press, a cold press, or a non-breathable sheet is laminated. Since the fiber comprising the polymer alloy constituting the fiber assembly of the present invention is thermoplastic, it is hot-pressed at a temperature above the softening point of the fiber or heated to the temperature and then cold-pressed or vacuum and / or compressed-air molded. The method is applied to a fiber assembly in which other thermoplastic fibers are mixed or a fiber assembly in which a thermoplastic resin is impregnated or mixed, depending on the temperature above the softening point of the thermoplastic fiber or the thermoplastic resin. In a fiber assembly in which hot pressing or heating to the above temperature and cold pressing or vacuum and / or pressure forming, impregnation or mixing with a thermosetting resin is performed, mainly at a temperature higher than the curing temperature of the thermoplastic resin. Hot press is applied.
[0030]
The molded product of the present invention may be a molded product composed of a fiber assembly and other members as well as a molded product composed of only a fiber assembly (molded product composed of one or more kinds of fiber assemblies). .
[0031]
The fiber assembly molded product of the present invention is excellent in dimensional stability, for example, interior materials such as automobile door trims, dashboards, ceiling materials, hood insulators, engine covers, heat insulating materials or soundproof materials, building materials for buildings, Used as wall material, heat insulating material, soundproofing material, etc.
[0032]
Hereinafter, the present invention will be described by way of examples. However, this invention is not limited only to the Example shown below.
[0033]
[Example 1]
A polymer alloy containing 40 parts by mass of polyamide (PA, nylon 6) as a crystalline thermoplastic resin, 60 parts by mass of polycarbonate (PC) as an amorphous thermoplastic resin, and maleic anhydride and an allyl ether copolymer as a compatibilizer. The fiber (1) having a fiber thickness of 2.2 dtex was obtained by discharging from a spinneret using a melt spinning machine.
In the production of fibers by the melt spinning machine (2), a chip-like or pellet-like polymer alloy is supplied from the root end hopper (4) of the extruder (3) as shown in FIG. ), The polymer alloy is extruded into the die (5) while being heated and melted, and discharged from the orifice (7) of the die (5) as shown in FIG. The hot air blowing ports (8) are opened on both sides of (7), hot air is blown obliquely downward from the hot air supply passage (6), and the fiber (1) as the polymer alloy discharge product is stretched and thinned. It was broken.
Using the fiber (1) having a length of 50 mm, a nonwoven fabric sheet having a basis weight of 100 g / m ² was obtained by a needle punching method.
Furthermore, the nonwoven fabric sheet was impregnated with a 50% solid content thermosetting resol-type phenol-formaldehyde initial condensate aqueous solution with a roll so as to be 20% of the basis weight of the nonwoven fabric sheet, and 130 ° C. in a dryer. After drying for 5 minutes, it was subjected to hot press molding at 200 ° C. for 30 seconds to obtain a molded product (A) having a thickness of 5 mm.
[0034]
[Comparative Example 1]
Without using a compatibilizer, a PA and PC mixture comprising the above PA, 40 parts by mass, and PC, 60 parts by mass was prepared, and the mixture was used in the same manner as in Example 1 to obtain A molded product (B) of 5 mm was obtained.
[0035]
(test)
The tensile strength (MPa) and bending strength (MPa) of the molded product (A) and molded product (B) obtained in Example 1 and Comparative Example 1 were measured according to JIS-K7113 and JIS-K7171. . The results are shown in Table 1.
[0036]
[Table 1]
[0037]
As is apparent from the results shown in Table 1, the molded product (A) using the polymer alloy fiber (1) containing the compatibilizer is superior to the comparative molded product (B) in tensile strength. And it was confirmed to have bending strength.
[0038]
[Example 2]
PP as crystalline thermoplastic resin, 60 parts by mass, styrene-modified polyphenylene ether (modified PPE) as non-crystalline thermoplastic resin, 40 parts by mass, partially hydrogenated alkenyl aromatic compound-conjugated diene block copolymer as compatibilizer The polymer alloy containing was discharged from the spinneret using the same melt spinning machine (2) as in Example 1 to obtain a fiber (1) having a fiber thickness of 1.1 dtex. The fiber (1) has a length of 150 mm, 80 parts by mass of the fiber (1), 20 parts by mass of a low-melting polyester fiber (melting point 110 ° C.), and a weight per unit area of 200 g / m ² by a needle punching method. A nonwoven fabric sheet having a thickness of 10 mm was obtained.
The nonwoven sheet is heated in a dryer at 180 ° C. for 3 minutes to partially melt the low-melting polyester fiber, and then the nonwoven sheet is taken out and immediately molded into a predetermined shape with a cold-pressing machine. A molded article having good and rigidity was obtained.
[0039]
Example 3
The mixed fiber obtained by mixing 50 parts by mass of the fiber (1) obtained in Example 2 above, 50 parts by mass of kenaf fibers (thickness 0.6 mm, length 100 mm), and a basis weight of 400 g by needle punching method. / M ² , a 10 mm thick nonwoven fabric sheet was obtained.
Furthermore, 100% by mass of the nonwoven fabric sheet was impregnated with 45% polypropylene emulsion so as to adhere to 40% by mass in solid content, and the nonwoven fabric sheet was further dried in a dryer at 100 ° C. for 10 minutes to evaporate water. The polypropylene is semi-melted in a dryer at 200 ° C. for 3 minutes, taken out of the dryer, and the nonwoven fabric sheet is molded into a predetermined shape with a cold press machine, forming with good moldability and rigidity. I got a thing.
[0040]
Example 4
PA (nylon 66) as a crystalline thermoplastic resin, 40 parts by mass, high impact polystyrene-modified polyphenylene ether as an amorphous thermoplastic resin, 55 parts by mass, styrene-butadiene thermoplastic elastomer as an impact modifier, 5 A polymer alloy containing an epoxy group-containing unsaturated monomer as a compatibilizing agent is discharged from the spinneret using the same melt spinning machine (2) as in Example 1, and the fiber thickness is 2.2 dtex. Fiber. The length of the fiber is 100 mm, the fiber, 40 parts by mass, kenaf fiber (thickness 0.2 mm, length 50 mm), and 60 parts by mass are mixed, and the needle punching method is used to obtain a thickness of 20 mm and a basis weight of 200 g / m ^2. A fiber sheet was obtained.
Next, a thermosetting resin aqueous solution comprising 88% of a 45% solids resol type alkylresorcin-formaldehyde initial condensate, 2% of a fluorine-based water repellent and 10% of a flame retardant is added to the fiber sheet. The fiber sheet was impregnated so that the adhesion amount was%, and dried at 120 ° C. for 3 minutes to obtain a thermosetting resin-impregnated sheet.
When this thermosetting resin-impregnated sheet was hot-press-molded into a predetermined shape at 180 ° C. for 45 seconds, a molded product having excellent moldability and excellent heat resistance and weather resistance was obtained.
[0041]
Example 5
A nonwoven fabric (PET, weight per unit area 30 g / m ² ) produced by the spunbond method is impregnated with the thermosetting resin aqueous solution of Example 4 so as to have a solid content of 20 g / m ² and dried at 100 ° C. for 2 minutes. The obtained skin material was further hot-pressed at 200 ° C. for 45 seconds on top of the three thermosetting resin-impregnated sheets obtained in Example 4 above, and the moldability was good. There was obtained a molded product having excellent heat resistance, weather resistance and water resistance.
[0042]
【The invention's effect】
The fiber, fiber assembly, and fiber assembly molded product of the present invention are excellent in step stability, formation, and heat resistance.
[Brief description of the drawings]
[Fig. 1] Explanatory drawing of melt spinning machine [Fig. 2] Cross section of die [Explanation of symbols]
1 fiber

Claims (12)

Polyamide and a crystalline thermoplastic resin, amorphous thermoplastic and polycarbonate one ninety-nine mass ratio as the resin 99: 1 relative to the mixture 100 parts by weight were mixed at a mass ratio, maleic anhydride as a compatibilizing agent A fiber obtained by melt spinning a polymer alloy to which 0.01 to 60 parts by mass of a copolymer of styrene and allyl ether is added . Partial hydrogen as a compatibilizing agent for 100 parts by mass of a mixture of polypropylene as a crystalline thermoplastic resin and styrene-modified polyphenylene ether as a non-crystalline thermoplastic resin in a ratio of 1:99 to 99: 1 by mass. A fiber obtained by melt spinning a polymer alloy added with 0.01 to 60 parts by mass of an added alkenyl aromatic compound-conjugated diene block copolymer. As a compatibilizing agent for 100 parts by mass of a mixture in which polyamide as a crystalline thermoplastic resin and high impact polystyrene-modified polyphenylene ether as an amorphous thermoplastic resin are mixed in a ratio of 1:99 to 99: 1 by mass. A fiber obtained by melt spinning a polymer alloy to which 0.01 to 60 parts by mass of an epoxy group-containing unsaturated monomer is added. The fiber according to any one of claims 1 to 3, wherein a rubber-like substance is added to the polymer alloy. A fiber assembly comprising the fiber according to any one of claims 1 to 3 . The fiber assembly according to claim 5, wherein vegetable fibers are mixed in the fiber assembly . The fiber assembly according to claim 5 or 6, wherein the fiber assembly is a web or a web laminate . The fiber assembly according to claim 7, wherein the fiber assembly is a nonwoven fabric in which a web or a web laminate is entangled by needle punching . The fiber assembly according to any one of claims 5 to 7 , wherein the fiber assembly is a nonwoven fabric in which fibers are bound together by a synthetic resin binder . The fiber assembly according to any one of claims 5 to 7 , wherein the fiber assembly is a non-woven fabric bound by thermal bonding . The fiber assembly according to claim 5 or 6 , wherein the fiber assembly is a fiber knitted fabric . A fiber assembly molded product obtained by heating and pressing the fiber assembly according to any one of claims 5 to 11 into a predetermined shape .