JPH07186283A - Thermoplastic resin composite material, production thereof and molded article obtained therefrom - Google Patents

Abstract

PURPOSE:To obtain a self-reinforcing type thermoplastic resin composite material excellent in handling properties and recovery reusability without employing an impregnation process being a subject of a fiber reinforced thermoplastic resin composite material. CONSTITUTION:In a thermoplastic resin composite material based on a fibril component composed of a crystalline thermoplastic resin (A) and a matrix component composed of a thermoplastic resin (B), a fibrile diameter is below 10mum and the aspect ratio of a fibril is 100 or more and fibrils are mutually arranged in an almost parallel state (a). The content of the crystalline thermoplastic resin (A) in the composite material is 10-80wt.% and the m.p. of (A) is higher than the m.p. or softening point of (B) by 10 deg.C or higher (b) and fibrils are uniformly dispersed in the cross section in the direction vertical to the orientation direction of the fibrils.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite material in which a reinforcing fiber and a matrix resin are both made of a thermoplastic polymer compound, a method for producing the composite material, and a molded product obtained from the composite material. By molding this composite material, a composite material molded body can be easily obtained.

[0002]

2. Description of the Related Art Glass fiber reinforced plastic (GFR
P) is a composite material of glass fiber and unsaturated polyester, vinyl ester resin, epoxy resin or the like, and these are problematic in recyclability because they use a thermosetting resin as a matrix resin.

On the other hand, a thermoplastic composite material (TPC) using a thermoplastic resin as a matrix resin and a glass fiber, a carbon fiber or the like as a reinforcing fiber is tough, does not require a curing reaction treatment, and has excellent recyclability. However, since the viscosity is significantly higher than that of the thermosetting resin, it is difficult to impregnate the reinforcing fibers as a matrix.

Further, Japanese Patent Application Laid-Open No. 3-244529 discloses a sheet-like material for composites, in which a reinforcing fiber and a thermosetting resin fiber are mixed and woven, and then the thermoplastic resin fiber is melted into a matrix, and a manufacturing method thereof. Although this facilitates the impregnation process, there is a problem that impregnation during melting is indispensable.

Further, Plastic Age Apr. 1989, p17
Liquid crystal polymers and thermoplastic resin alloys are disclosed in 4 to 180, and the property of liquid crystal polymers that is rigid and easy to align is utilized, and after melt blending with the thermoplastic resin, the liquid crystal polymers are made into oriented fibers during injection molding. Although researches have been conducted to form them and improve their mechanical properties, liquid crystal polymers are expensive, and there are problems such as the need to add 50% or more of liquid crystal polymers to improve the properties.

In addition, Journal of the Textile Society, Vol. 38, No. 1 (1982),
p87-95, Vol.38, No.4 (1982), p43-52, describes melt-spinning of polypropylene / polystyrene mixed system. Two components of thermoplastic resin are mixed and melt-spun to form ultrafine fibers. Although there are studies on blending characteristics and mechanical properties, there is no description about further stretching and stretching after spinning, and neither is the molded composite material obtained.

[0007]

The object of the present invention is to provide a self-reinforced thermoplastic resin composite which does not require an impregnation step, which is a problem of the fiber-reinforced thermoplastic resin composite material, and is excellent in handleability and recovery / reusability. To provide a material and a molded body thereof.

[0008]

The present invention relates to a thermoplastic resin composite material comprising, as a main component, a fibril component composed of a crystalline thermoplastic resin (A) and a matrix component composed of a thermoplastic resin (B). The fibril diameter is less than 10 μm, the aspect ratio is 100 or more, and the fibrils are arranged in a substantially parallel state. (B) The content of the crystalline thermoplastic resin (A) in the composite material is 10 to 80% by weight. Then, (A)
Thermoplastic resin having a melting point of 10 ° C. or more higher than the melting point or softening temperature of (B), and (c) the fibrils are uniformly dispersed in a cross section in a direction perpendicular to the fibril arrangement direction. The present invention relates to a composite material, a method for producing the composite material, and a molded body obtained by molding the composite material.

In the present invention, the fiber-reinforced thermoplastic resin composite material can be produced, for example, by the following method.

A crystalline thermoplastic resin (A), a compatibilizer for uniformly dispersing the thermoplastic resins (B) and (A), (B), other interface modifiers, fillers, colorants, etc. Dry blend the additives in and mix.

The mixture is melt-kneaded and dispersed at a temperature not lower than the melting point of the crystalline thermoplastic resin (A) with a biaxial kneader, a kneader or the like.

The kneaded product is continuously extruded in a strand form or a sheet form with an extruder, a spinning machine or the like, and further 3 m / min or more,
It is preferably stretched and wound at a speed of 20 to 500 m / min. It can also be performed by inflation molding. As a result, a two-component composite type strand or sheet of crystalline thermoplastic resin (A) and thermoplastic resin (B) is obtained.

Further, this is uniaxially stretched 2 to 10 times by a stretching device to increase the degree of orientation and crystallinity of the crystalline thermoplastic resin (A), so that it is less than 10 μm, preferably 0.1 to
A fiber reinforced thermoplastic resin composite material containing a 1 μm diameter ultrafine fibrous crystalline thermoplastic resin (A) and a thermoplastic resin (B) as main components is obtained.

The crystalline thermoplastic resin (A) used is a melt-spinnable polyamide (PA) or polyester (PE).
s), polypropylene (PP), polyethylene (P
E), polyacetal and the like are preferable, but not limited to these.

On the other hand, the thermoplastic resin (B) forming the matrix, regardless of whether it is crystalline or amorphous, has a melting point or softening point lower than the melting point of the crystalline thermoplastic resin (A) by 10 ° C. or more. To be selected. For example, polyethylene (PE),
Polyolefin such as polypropylene (PP), polyester such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), polystyrene (P
S), polyvinyl chloride (PVC), acrylonitrile-
Butadiene-styrene resin (ABS), polyamide (P
A), polycarbonate (PC), polyacetal (P
OM), polyphenylene ether (PPE), polymethyl methacrylate (PMMA), crystalline polybutadiene and the like.

Examples of the compatibilizer include carboxy-modified polypropylene and maleic anhydride-modified polypropylene (P
P), ionomer, carboxylic acid, acid modified polyethylene (PE), ethylene / methacrylic acid copolymer, maleic anhydride grafted styrene / ethylene butadiene /
Styrene block copolymer (SEBS), ethylene / ethyl acrylate copolymer, maleic anhydride grafted ethylene propylene rubber (EPR), polyacrylic acid imide, SEBS, styrene / butadiene / styrene block copolymer (SBS), ethylene Propylene diene monomer (EPDM) copolymer, PP / EPDM copolymer,
Polymethylmethacrylate (PMMA) / EPDM copolymer, PE / polystyrene (PS) copolymer, ethylene / glycidyl methacrylate copolymer, styrene / maleic anhydride copolymer, ethylene / acrylic ester /
Maleic anhydride copolymer, ethylene / ethyl acrylate copolymer, ethylene / ethyl acrylate / maleic anhydride copolymer, glycidyl methacrylate / vinyl monomer copolymer, ethylene / methacrylic acid / acrylic ester copolymer, Ethylene / glycidyl methacrylate / vinyl acetate copolymer, maleated ethylene /
Propylene rubber, ethylene-vinyl acetate (EV
A) Copolymer, ethylene / vinyl acetate / maleic anhydride copolymer, EPDM / EVA / low density polyethylene (LDPE) copolymer, SBS / EPDM / EVA /
LDPE copolymer etc. can be mentioned. As the additive, for example, an interface modifier, a filler, a colorant, etc. can be used.

The fiber-reinforced thermoplastic resin composite material of the present invention is preformed into, for example, a filament shape, a tape shape, a sheet shape, a film shape, a strand shape, a pellet shape, and the like, which is then filament winding molding, laminated press molding,
A molded product can be obtained by injection molding or the like and is useful as a precursor of the molded product.

[0018]

EXAMPLES The present invention will be described in more detail below with reference to examples.

Example 1 Nylon 6 pellet [Toyobo Co., Ltd., T-850, mp]
= 215 ° C], polypropylene pellets [Showa Denko KK]
Manufactured by YOYO-ALOMAR MA-410, mp = 165 ° C.) and a compatibilizing agent [Venezto GR-25 manufactured by Nagase & Co., Ltd.] at a weight ratio of 50/50/5, respectively, and blended into a biaxial kneader. Melted and kneaded at 240 ° C. under the condition of screw rotation speed of 100 RPM. After crushing the kneaded product, it was kneaded and extruded at 240 ° C. by an extruder equipped with a strand-shaped die having a diameter of 3 mm and taken at a speed of 8 m / min to obtain a strand-shaped extrudate having a diameter of about 1 mm. It was further stretched 3 times at room temperature to obtain a strand-shaped stretched product. This serves as a precursor for molding the fiber-reinforced thermoplastic resin composite material. This strand-shaped precursor is arranged in one direction, stacked, and hot pressed at 180 ° C to 2 mm
A thick sheet-shaped compact was obtained. Punched into a dumbbell shape,
A tensile test was conducted in the fiber axis direction at 100 mm / min to determine the tensile breaking strength.

Example 2 Polypropylene [Showa Denko K.K.
A-410, mp = 165 ° C.], low density polyethylene [Showa Denko KK, Cyolex, mp = 105 ° C.] and compatibilizer [Nagase Sangyo KK, Veneto GR-25] 40/60 respectively The mixture was dry blended at a weight ratio of / 5 and melt-kneaded in a twin-screw kneader at 180 ° C. under the condition of a screw rotation speed of 100 RPM. After crushing the kneaded product, it was kneaded and extruded at 240 ° C. by an extruder equipped with a strand-shaped die having a diameter of 3 mm and taken at a speed of 8 m / min to obtain a strand-shaped extrudate having a diameter of about 1 mm. It was further stretched 5 times at room temperature to obtain a strand-shaped stretched product. This serves as a precursor for molding the fiber-reinforced thermoplastic resin composite material. This strand-shaped precursor is arranged in one direction, stacked, and hot pressed at 130 ° C to 2 mm
A thick sheet-shaped compact was obtained. Punched into a dumbbell shape,
A tensile test was conducted in the fiber axis direction at 100 mm / min to determine the tensile breaking strength.

Comparative Example 1 Nylon 6 was extruded into a strand at a temperature of 240 ° C.
Collect at 8m / min. Then, after stretching 3 times at room temperature,
Arrangement, stacking and hot pressing at 240 ° C. were carried out in the same manner as in the example to obtain a sheet-shaped molded product having a thickness of 2 mm. It was punched into a dumbbell shape and subjected to a tensile test in the fiber axis direction at 100 mm / min to determine the tensile breaking strength.

COMPARATIVE EXAMPLE 2 Polypropylene was extruded in strands at a temperature of 180 ° C. and taken up at 8 m / min. Then, the sheet was stretched 8 times at room temperature, arranged and stacked in the same manner as in the example, and heat-pressed at 180 ° C. to obtain a sheet-shaped compact having a thickness of 2 mm. It was punched into a dumbbell shape and subjected to a tensile test in the fiber axis direction at 100 mm / min to determine the tensile breaking strength.

Comparative Example 3 Low-density polyethylene was extruded at a temperature of 130 ° C. in a strand shape and taken out at 8 m / min. Then, after stretching 5 times at room temperature, the sheets were arranged, stacked and heat-pressed at 130 ° C. in the same manner as in Example to obtain a sheet-shaped molded product having a thickness of 2 mm. Punched into a dumbbell shape, tested at 100 mm / min in the fiber axis direction,
The tensile breaking strength was determined.

The results of Examples 1 and 2 and Comparative Examples 1 to 3 are shown in Table 1. A cross-sectional SEM photograph showing the shape of the fibers of the molding precursor strand is shown in FIG. 1, and a cross-sectional SEM photograph showing the shape of the fibers in the composite material molded product sheet is shown in FIG. In Examples 1 and 2, the composite material molded products were nylon 6 and P, respectively.
It can be seen that the tensile strength is significantly higher than that of a sheet formed of a single material, which is reinforced with ultrafine P fibers.

[0025]

[Table 1]

Examples 3 to 5 and Comparative Examples 4 to 5 Nylon 6 pellets [manufactured by Toyobo Co., Ltd., T-850, mp]
= 215 ° C.) and polypropylene pellets (Showa Denko KK, Shiyo Aroma MA-410, mp = 165 ° C.) were changed in the same manner as in Example 1 except that the ratios were changed as shown in Table 2. I got a thing. This serves as a precursor for molding the fiber-reinforced thermoplastic resin composite material. This strand-shaped precursor was arranged in one direction, stacked, and hot pressed at 180 ° C. to obtain a sheet-shaped molded product having a thickness of 2 mm. It was punched into a dumbbell shape and subjected to a tensile test in the fiber axis direction at 100 mm / min to determine the tensile breaking strength. The results are shown in Table 2.

[0027]

[Table 2] (* A) The precursor strands are not fused to each other and cannot be molded.

[0028]

Since the present invention is a fiber reinforced composite material of thermoplastic materials, it is excellent in recyclability. In the melt-kneading-extrusion stretching process, fibers are formed in the matrix material, so that the adhesiveness at the interface is excellent. Since it is reinforced with ultrafine thermoplastic fibers, it has excellent smoothness on the surface of the molded product.

[Brief description of drawings]

FIG. 1 is a cross-sectional SEM photograph showing the shape of fibers of a molding precursor strand of Example 1.

2 is a cross-sectional SEM photograph showing the shape of fibers in the composite material molded product sheet of Example 1. FIG.

Claims (4)

[Claims] 1. A thermoplastic resin composite material comprising a fibril component composed of a crystalline thermoplastic resin (A) and a matrix component composed of a thermoplastic resin (B) as main components,
(a) The fibril diameter is less than 10 μm, the aspect ratio is 100 or more, and the fibrils are arranged in a substantially parallel state. (b) The content of the crystalline thermoplastic resin (A) in the composite material is 10 to At 80% by weight, the melting point of (A) is 10 ° C or more higher than the melting point or softening temperature of (B), and (c) the fibrils are uniformly dispersed in the cross section in the direction perpendicular to the fibril arrangement direction. A thermoplastic resin composite material characterized by the above. 2. A crystalline thermoplastic resin (A), a thermoplastic resin (B), a compatibilizer and other additives are melt-mixed at a temperature equal to or higher than the melting point of the crystalline thermoplastic resin (A), A method for producing a thermoplastic resin composite material, which comprises extruding, stretching, and then stretching. 3. A thermoplastic resin composite material molded body obtained by molding the composite material according to claim 1. 4. The thermoplastic resin composite material molding, wherein the composite material according to claim 1 is molded at a molding temperature lower than the melting point of (A) and higher than the melting point or softening temperature of (B). Body manufacturing method.