JPH115909A - Reinforced resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin composition excellent in rigidity and impact strength and having characteristics, such as capability of being nailed, necessary for use as a wood substitute by blending a thermoplastic resin with polyacrylonitrile fibers and a filler comprising an organic natural material. SOLUTION: This composition contains 98-19 wt.% thermoplastic resin, 1-50 wt.% polyacrylonitrile fibers, and 1-80 wt.% filler comprising an organic natural material. The thermoplastic resin used preferably comprises a polyethylene or polystyrene, although not limited in particular. The polyacrylonitrile fibers used comprises fibers of an acrylonitrile homopolymer or a copolymer of at least 90 wt.% acrylonitrile and at most 10 wt.% copolymerizable vinyl monomer. It is desirable that the fibers have a fineness of 0.5-50 denier, a tensile strength of at least 2.5 g/d, an initial modulus of at least 30 g/d, and a fiber length of 0.5-20 mm. The filler mainly used comprises woodflour.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a polyacrylonitrile fiber and an organic natural filler-reinforced resin composition. In particular, it is used for wood replacement.

[0002]

2. Description of the Related Art Thermoplastic resins have excellent moldability and impact resistance, and are used in various fields such as automobile parts, home electric appliance parts, and OA equipment. However, compared to other materials (especially metal materials), the rigidity is inferior, and to strengthen it,
Products reinforced with fibers such as glass fibers, carbon fibers, and aramid fibers are known.

Japanese Patent Application Laid-Open No. 63-81162 discloses an invention in which a thermoplastic resin is reinforced with polyacrylonitrile fibers, and Japanese Patent Application Laid-Open No. Hei 5-70698 discloses a friction comprising a polyacrylonitrile fiber, a thermosetting resin and a filler. JP-A-3-45637 discloses a flame-retardant electrical insulating composition comprising a polyolefin, an inorganic flame retardant and a polyacrylonitrile fiber.
Japanese Patent Application Laid-Open No. 3-45637 discloses a friction material made of an acrylic fiber having a specific shape, a filler, a resin such as a phenol resin, an epoxy resin, a polyimide resin, a melamine resin, or a natural or synthetic rubber. The publication discloses a flame-retardant electric insulating composition comprising a polyolefin, an inorganic flame retardant and a polyacrylonitrile fiber, as disclosed in JP-A-8-8.
No. 5761 discloses a composition comprising a thermoplastic resin, polyacrylonitrile fiber, and an inorganic filler.

[0004] On the other hand, there have been many examples of adding organic natural fillers such as wood flour to thermoplastic resins. Research has shown that natural products can provide peace of mind and are indispensable as an ingredient in artificial wood. But,
Simply adding wood powder or the like increases the modulus of elasticity but has the disadvantage of becoming brittle. In order to prevent this, there is a method of kneading cellulosic fibers and the like, but cellulosic fibers are particularly vulnerable to heat and use relatively large extruders in industrial production. Is not strengthened. In addition, one of the necessary characteristics of artificial wood,
It has nailing and nail holding properties. It is necessary to satisfy these characteristics.

[0005] For example, JP-A-57-180648 describes an invention relating to a polypropylene composition comprising polypropylene and / or modified polypropylene, wood flour, and organic fibers. However, vinylon fibers and jute fibers are used as organic fibers, and the effect of improving impact strength is low.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a natural substance-filled composite which is excellent in both physical properties such as rigidity and impact strength. Particularly, in a thermoplastic resin, a natural filler is used to increase rigidity, and an elastomer component is usually added to increase impact strength. When an elastomer component is added, impact strength is improved but rigidity is reduced.

An object of the present invention is to provide a natural filler composite having excellent physical properties of both rigidity and impact strength, and to impart properties such as nailing required for wood replacement. Things.

[0008]

Means for Solving the Problems The present inventors have solved the above problems by using a natural filler and a polyacrylonitrile fiber in combination. That is, the present invention is as follows. 1) (a) 98 to 19% by weight of a thermoplastic resin, (b) 1 to 50% by weight of a polyacrylonitrile fiber, and (c)
A resin composition comprising 1 to 80% by weight of an organic natural product filler.

2) The resin composition as described in 1 above, wherein the organic natural filler is wood flour. 3) A wood substitute material comprising the resin composition according to 1 or 2 above. Hereinafter, the present invention will be described in detail. The thermoplastic resin in the present invention includes low, medium and high density polyethylene (hereinafter, high density polyethylene is abbreviated as HDPE), polypropylene, polyvinyl chloride, polystyrene, acrylonitrile-styrene copolymer, acrylonitrile-butadiene-
Examples include styrene copolymers, polyamides, polyacetals, polycarbonates, polyethylene terephthalates, polybutylene terephthalates, polyphenylene ethers, styrene-butadiene copolymers, and hydrogenated compositions thereof. These thermoplastic resins can be used alone or in combination of two or more. Among these thermoplastic resins, polyethylene and polystyrene are particularly preferable.

The polyacrylonitrile fiber in the present invention is a polyacrylonitrile polymer fiber composed of acrylonitrile homopolymer or a copolymer of 90% by weight or more of acrylonitrile and 10% by weight or less of a vinyl monomer copolymerizable with acrylonitrile. The production method is a fiber produced by a generally known method for producing a polyacrylonitrile-based polymer fiber. Among them, the polymerization ratio of the vinyl monomer to be copolymerized is more preferably 5% or less, further preferably 3% or less.

Further, it is more preferable that the fiber is stretched by heating, and the fiber stretched by heating at 140 ° C. or more, preferably 170 ° C. or more is more preferably used. The polyacrylonitrile fiber in the present invention has a fineness of 0.5 to 50 denier and a tensile strength of 2.5 g / d or more, preferably 5.0 or more.
g / d or more, more preferably 8.0 g / d or more, and the initial elastic modulus is preferably 30 g / d or more.

[0012] The fiber length of the polyacrylonitrile fiber in the present invention is preferably 0.5 to 20 mm, more preferably 1 to 10 mm, more preferably 2 to 6 m.
m. If it is less than 0.5 mm, industrial production is difficult. In addition, it is preferable to use a longer one to obtain the reinforcing effect,
If it exceeds 20 mm, the polyacrylonitrile-based fibers are kneaded in a thermoplastic resin, and when extruded, the polyacrylonitrile-based fibers may be entangled with each other, resulting in poor dispersibility and poor physical properties.

The composite reinforced resin composition of the present invention contains 1 to 50% by weight, preferably 2% by weight of polyacrylonitrile fiber.
To 40% by weight, more preferably 3 to 25% by weight. If the amount of the polyacrylonitrile fiber is too small, the effect of the present invention is not achieved, and if it is too large, the moldability is impaired, which is not preferable. The organic natural product-based filler in the present invention mainly refers to wood flour obtained by finely grinding wood. The raw material wood is not particularly limited, but examples include cypress, cedar, pine, toga, fir, hippo, maple, sen, tamo, oak,
Beech, oyster, cherry, hornbeam, camellia, sina, shii, tochi, dronoki,
Japanese cypress, Mizume, Beetzga, Beech pine, Maple, Alder, Rubber tree, Ramin, Rawan, Terentan, Mango, Rengas, Lansingbok, Chatchinmodoki, Nurde, Urushi, Hazenoki, Harigiri, Hannoki, Birch, Asada, Kissage, Tabebuya, Ibe, Gayakan, Corzia, Canary Wood, Canalium, Katsura, Terminaria, Idygbo, Afara, Elima, Mersawa, Parosapis, Chengal, Resak, Apithon, Kruin, Jan, Tuter, Dona, Kapoor, Yakar, Meranti, Upna, Kakinoki, Kokutan, Butabuta , Chestnuts, Bintangol, Santa Maria, Carofilm, Gerongan, Garcinia, Manil, Isoki, Walnut,
Nogurumi, Kusunoki, Quinland Walnut, Villian, Tabunoki, Green Heart Acacia, Coclojua,
African teak, Afzeria, Alnus, Acre, Albizia, False Acacia, Magnolia, honoki, Kaya,
Mulberry, Eucalyptus, Platanus, Rowan, Poplar, Mokkoku, Zelkova, Elm, Teak, Mahogany, Ginkgo,
Abies fir, larch, yew, kaya and the like.

In addition, the organic natural product filler includes rice husk, peach kernel, apricot kernel, walnut shell, corn cob, and the like. The resin composition of the present invention is added with 1 to 80% by weight of an organic natural filler. Preferably, it is added in an amount of 5 to 70% by weight, more preferably 20 to 60% by weight. If the addition amount is small, no effect is exhibited, and if the addition amount is large, it becomes extremely brittle, which is not preferable.

In the resin composition of the present invention, inorganic fillers, antistatic agents, various stabilizers, nucleating agents, plasticizers, flame retardants, pigments, coloring agents, etc. are known as long as their characteristics are not impaired. It can be used by appropriately adding it according to the method. The resin composition of the present invention can be used particularly effectively for uses such as wood replacement. For example, building materials (baseboard, surrounding edges, beams, wet edges, flooring materials, ceiling materials, etc.), window frame sashes, rails such as bran windows, around baths (bath lids, bath tubs, pens, etc.), around kitchens , Concrete formwork, piles, fences, and pallets for carrying cargo.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described specifically with reference to examples, but the present invention is not limited to these examples. In addition, each measurement is performed on condition of the following. Izod impact strength; measured according to ASTM D-256. Flexural modulus; measured in accordance with ASTM D-790.

Vibration control: The reverberation time measured by the central vibration method is expressed as a relative value with the value of the system of HDPE / wood flour = 50/50 (Comparative Example 2) being 100. The smaller the value, the better the damping performance. Nailability: 2.15 thickness at the center of 15 mm from the end of a compression molded product having a length of 65 mm, a width of 12 mm and a thickness of 3 mm
Use a hammer to drive an mm round nail. At this time, a mark that can be nailed without any problem is indicated by ○, a mark that breaks the molded article is indicated by x, and a mark that can be nailed but cracks the molded article is indicated by Δ.

Nail Retention: A pull-out test is carried out with the handle of the head of the nail hit by the method described above. Objects that cannot be pulled out by hand are represented by ○, and objects that can be pulled out by hand are represented by ×.

[0019]

Example 1 A polyacrylonitrile-based fiber (acrylonitrile homopolymer fiber) having a strength of 13 g / d and an initial modulus of elasticity of 60 g / d with 3000 denier / 1000 filaments was converted to a bisphenol A type epoxy resin (Asahi Kasei Kogyo Co., Ltd.). AER661) is dipped and passed through an emulsion having a concentration of 8% by weight, dried, and cut into 3 mm length polyacrylonitrile fiber chopped strands.

10% by weight of this polyacrylonitrile fiber chopped strand (hereinafter abbreviated as PAN fiber), 50% by weight of HDPE (J311 manufactured by Asahi Kasei Kogyo Co., Ltd.), and 40% by weight of wood flour (pine) were mixed. 2 using an extruder (Twin Screw Extruder 2D20S, manufactured by Toyo Seiki Seisaku-sho, Ltd.)
The mixture is melt-kneaded at 00 ° C., and further molded by a compression molding machine to prepare a test piece for evaluation.

[0021]

Example 2 and Comparative Examples 1 and 2 Specimens were prepared in the same manner as in Example 1 except that the components were added at the ratios shown in Table 1.

[0022]

Examples 3 and 4 and Comparative Examples 3 and 4 Test pieces were prepared in the same manner as in Example 1 except that the components were added in the ratios shown in Table 2. HIPS uses polystyrene 433 manufactured by Asahi Kasei Corporation.

[0023]

Comparative Example 5 A polyacrylonitrile fiber (acrylonitrile copolymer fiber; copolymer content: 15% by weight) having a performance of 3000 denier / 1000 filament, strength of 2 g / d and initial modulus of elasticity of 60 g / d was converted to bisphenol A type. Epoxy resin (AER66 manufactured by Asahi Kasei Corporation)
After dipping and passing through the emulsion liquid having a concentration of 8% by weight in 1) and drying, a chopped strand of polyacrylonitrile fiber cut to a length of 3 mm is prepared. Thereafter, evaluation was made in the same manner as in Example 1, and as a result, the Izod impact strength was 3.7.
kg · cm / cm.

Tables 1 and 2 show the evaluation results of Examples and Comparative Examples. As can be seen from these tables, the addition of polyacrylonitrile-based fibers has improved the Izod impact strength without reducing rigidity. It turns out to be excellent. This is the same in the examination results of the HIPS system as well as the HDPE system.

[0025]

[Table 1]

[0026]

[Table 2]

[0027]

The resin composition of the present invention is excellent in both rigidity and impact strength, excellent in vibration damping properties and nailing properties, and is a good wood substitute material as compared with the comparative example of the conventional product. is there.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI C08L 97/02 C08L 97/02 // (C08L 101/00 33:20 97:02)

Claims (3)

[Claims] (A) 98 to 19% by weight of a thermoplastic resin,
A resin composition comprising (b) 1 to 50% by weight of a polyacrylonitrile fiber and (c) 1 to 80% by weight of an organic natural filler. 2. The resin composition according to claim 1, wherein the organic natural product filler is wood flour. 3. A wood substitute material comprising the resin composition according to claim 1 or 2.