JPS601235A - Glass fiber-reinforced polyolefin resin composition - Google Patents

Abstract

PURPOSE:To provide a polyolefin resin compsn. having excellent mechanical strength, by melt-kneading glass fiber, an unsaturated silane compd., an org. carboxylic acid, and a free radical generating agent with a polyolefin. CONSTITUTION:50-99pts.wt. polyolefin, 1-50pts.wt. (per 100pts.wt. polyolefin) glass fiber, 0.1-5pts.wt. (per 100pts.wt. glass fiber) unsaturated silane compd., 0.01-5pts.wt. org. carboxylic acid or anhydride and 0.005-0.5pts.wt. (per 100 pts.wt. polyolefin) free radical generating agent are melt-kneaded together. Preferred polyolefin resins include crystalline polypropylene and a crystalline ethylene/propylene copolymer. Preferred carboxylic acid and its anhydride include C1-C3 carboxylic acids. Preferred free radical generating agents include org. peroxides having a decomposition temp. of 120 deg.C or above at which the falf life period for decomposition is 1min.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a glass fiber reinforced polyolefin resin composition having excellent mechanical strength.

Glass fiber-reinforced polyolefin resins have superior mechanical properties, heat resistance, and dimensional stability than regular polyolefin resins, so their application to automobile parts, electrical appliance parts, and various industrial parts is expanding. .

Conventionally, various proposals have been made for achieving interfacial modification or interfacial adhesion between glass fibers and polyolefin resins in order to improve the physical properties of glass fiber reinforced polyolefin resin compositions. For example, (1) a method in which an unsaturated silane compound and a radical generator coexist (Japanese Patent Publication No. 49-41098, etc.), (2) a polyolefin resin containing silane-treated glass fiber and a polyfunctional compound that can react with the silane, Method of adding and mixing the upper part and a radical generator
96, etc.), (3) A method of adding organic carzenic acid or its acid anhydride to glass fiber and polyolefin surface-treated with an aminoalkylsilane compound (Japanese Patent Publication No. 49-49029), (4) A method of adding and mixing glass fibers treated with a silane compound having an organic group that reacts with acids to a polyolefin resin modified with an unsaturated cal-7 acid or its anhydride (Japanese Patent Publication No. 51-10
No. 265, etc.). However, the conventional method (1
Methods Fi), (2), and (3) are simple, but the effect of improving mechanical strength is not sufficient, and the conventional method (4) requires modification to obtain a sufficient effect of improving mechanical strength. Since a large amount of modified polyolefin-' resin is required, and a polyolefin resin that has been modified in advance must be manufactured or obtained, the process is complicated and economically expensive.

The present invention was completed based on the discovery that the mechanical strength of the composition can be dramatically improved by improving the conventional method with an extremely simple solution.

That is, the present invention includes 50 to 99 parts by weight of polyolefin, 1 to 50 parts by weight of glass fibers based on the polyolefin, 0.1 to 5 parts by weight of an unsaturated silane compound and 0.01 parts by weight based on 100 parts by weight of the glass fibers. ~5 parts by weight of an organic carboxylic acid or its acid anhydride and the polyolefin 1
The present invention relates to a glass fiber-reinforced polyolefin resin composition obtained by melt-kneading 0.00 parts by weight with 0.005 to 0.5 parts by weight of a radical generator.

Examples of the polyolefin resin in the present invention include crystalline polypropylene, crystalline ethylene-zolopylene copolymer, polyethylene, polybutene, homopolymer of α-olefin such as poly-4-methylpentene-1, and α-olefin and other polymers. A copolymer with copolymerizable monomers such as olefins, aromatic olefins, and dienes, and mixtures thereof or less than 50% by weight of distoners,
Mixtures with other #'4 polymers are also possible. Particularly suitable are crystalline polypropylene and crystalline ethylene-propylene copolymer.

The unsaturated silane compound in the present invention is an organic silane having an ethylenic double bond and a group capable of forming a silanol group in the molecule, and even tf? Preferred are nyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, γ-acryloyloxyzolopyltrimethoxysilane, and mixtures of two or more of them are also possible. The amount of these unsaturated silane compounds to be used is in the range of 0.1 to 5 parts by weight, more preferably 0.3 to 3 parts by weight, based on 100 parts by weight of glass fiber. If it is less than the above range, no improvement in mechanical strength will be obtained, and if it is above the above range, the rate of improvement in mechanical strength will be small, the cost will be high, and heat resistance may deteriorate, discoloration, etc. may easily occur.

The organic carboxylic acid or its acid anhydride in the present invention can be of any type, and may be an aliphatic carboxylic acid, an aromatic carboxylic acid, a monocarboxylic acid, or a dicardic acid. It may be a saturated carboxylic acid or an unsaturated carboxylic acid, and may have other kinds of functional groups. For example, acetic acid, propionic acid, capric acid, lauric acid, stearic acid, acrylic acid, methacrylic acid, oleic acid, succinic acid, adipic acid, nananocin, maleic acid, fumaric acid, itaconic acid, citraconic acid, lactic acid. Typical examples include citric acid, phthalic acid, benzoic acid, toluic acid, and the like. Particularly preferred are carboxylic acids having 3 to 10 carbon atoms.

In addition, these acid anhydrides are also possible, but maleic acid,
Acid anhydrides such as succinic acid, phthalic acid, and cytosiconic acid are useful. The above acids and acid anhydrides may be used alone, but
You may use it as a mixture of 2 or more types. The amount of the organic carboxylic acid or its acid anhydride used is in the range of 0.01 to 5 parts by weight, more preferably 0.1 to 1 part by weight, based on 100 parts by weight of glass fiber.

In addition, the amount used for the unsaturated silane compound is preferably in the range of 1/λθ to 26)/1 in terms of weight ratio, but 1/10
Sufficient improvement effects can be obtained even with the usage amount in the range of ~V1.

If the amount used is less than the above range, the mechanical strength improvement effect will not be sufficient, and if it is more than the -F range, the rate of increase in the improvement effect will be small, and discoloration, odor, etc. may occur. It becomes easier.

Examples of the radical generator in the present invention include organic peroxides and azo compounds. Particularly suitable are organic peroxides having a decomposition temperature of 120° C. or higher and a half-life of 1 minute. For example, knzoylnoseoxide,
dicumyl peroxyr.

2,5-dimethyl-2,5-di(heavy-butylnomino-oxy)hexane, 2,5-dimethyl-2,5-di(t-butyl iR-oxy)hexyne-3,1,3-bis(t −
iflunozo-oxyisozolopyl) 4-enzene, 1.4-
Examples include bis(t-dityl/ξ-oxyisozolobyl)benzene, di-butyl peroxide, cumene hydroperoxy'Y, and t-butyl mono-benzoate, and they can also be used as a mixture of two or more. The use of these radical generators varies depending on the type of polyolefin, the amount of glass fiber, and the t1 crosstalk conditions of the unsaturated silane compound, but it is usually 0.0 parts by weight per 100 parts by weight of the polyolefin.
05 to 0.5 parts by weight, more preferably 0.01 to 0.1
Parts by weight range. If the amount is less than the above range, the mechanical strength improvement effect will not be sufficient, and if it is more than the above range, too many polymer radicals will be generated, resulting in crosslinking and main chain scission, resulting in poor physical properties and moldability. I also don't like it.

The glass fibers used in the present invention are usually commercially available glass fibers, and are usually surface-treated with aminosilane, epoxysilane, vinylsilane, acrylic silane, etc., but fibers treated with any of these are also possible. ,
Also, it may not be processed.

Usually, the glass fibers are preferably chopped strands cut into lengths of 3 m + 16 ra, etc., but long fiber rovings may be supplied and broken during kneading.

In the composition of the invention, the concentration of glass fibers is between 1 and 50
% by weight, more preferably in the range 3-40% by weight.

When the amount is less than the above range, the reinforcing effect of the glass fiber is small, and when it is more than the above range, the reinforcing effect is saturated, and moldability, appearance of the molded product, etc. deteriorate (2).

Various methods are possible for producing the composition of the present invention, and the above components may be premixed using a cone blender, ribbon blender, etc. to form a tri-blend composition, which is then fed to various molding machines and melt-molded. Alternatively, the premix may be melt-kneaded and granulated using a single-screw extruder, twin-screw extruder, etc. to obtain a pellet-like composition, which is then subjected to various moldings.

The molding material obtained as a tri-blend composition or a pellet-like composition according to the present invention can be molded into various molded products, sheets, rods, and A-shaped products by commonly used melt molding methods such as injection molding, extrusion molding, and compression molding. be done.

In addition to the above-mentioned components, the composition of the present invention includes a heat stabilizer, an ultraviolet absorber, an antistatic agent, a lubricant, a filler, a flame retardant, a colorant,
It may contain various additives such as a crystal nucleating agent.

Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples. All parts and parts in Examples and Comparative Examples are parts by weight.
Expresses weight %.

In addition, mechanical strength was measured by measuring tensile strength and bending properties. The measurement method was as follows.

Tensile strength: A8'rM D638, 9/- in units Bending strength: A8'rM D790. Unit Kf/ct; 1 Flexural modulus: A8TM D790, Unit Kf/d Example 1-1-6 Crystalline polyzolopyrene with MFI 4.0, r-methacryloyloxypropyltrimethoxysilane, maleic acid,
After thoroughly mixing 2,5-dimethyl-2,5-di(t-butylperoxy)hexane in the proportions listed in Table 1, the surface was treated with γ-aminopropyltriethoxysilane having a length of 3wIII+ and a diameter of 13μ. The chopped glass fiber P was added and mixed, and the mixture was fed to an extruder and heated at 230°C.
The mixture was melt-kneaded and pelletized. A test piece was made from the obtained pellet by injection molding, and the mechanical strength was measured17.
Ta. The results are shown in Table 1.

Comparative Examples 1-1 to 5 Composition pellets were produced in the same manner as in Example 1 except that the quantitative ratio of each component was changed to the ratio shown in Table 1, and the mechanical strength was measured. The results are shown in Table 1.

Comparative Example 2 MFI graft-modified with 0.3 parts of maleic anhydride
A pellet composition was prepared using an extruder in the same manner as in Example 1 using 70 parts of crystalline polyzolopyrene No. 8 and 30 parts of the glass fiber used in Example 1, and evaluated. The results are shown in Table 1.

Example 2 Composition pellets were prepared in the same manner as in Example 1-1, except that various organic cardinic acids and acid anhydrides were used in place of maleic acid in Example 1-1. It was manufactured and its mechanical strength was measured. The results are shown in Table 2.

Table 2 Example 3 In Example 1-5, a composition was prepared in the same manner as in Examples 1-5, except that high-density polyethylene with an MI of 20 and a density of 0.962 was used in place of the crystalline polyzolopyrene. Pellets were manufactured and mechanical strength was measured. The tensile strength was 820 KqlcJ, and the bending strength was 1210 Kv'cJ.

Comparative Example 3 Composition pellets were produced in the same manner as in Example 3, except that only high-density polyethylene and glass fiber were used, and the mechanical strength was measured. The tensile strength was 5 B□Kg/lyi, and the bending strength was 690Kp/no.

The composition of the present invention has excellent mechanical strength, particularly tensile strength and bending strength, which exhibit extremely high values. According to the invention,
By filling 20 inches of glass fiber, the tensile strength that would require 30% glass fiber filling in the conventional composition,
It is possible to develop a value that approximates the bending strength. Being able to reduce the amount of glass fiber filled has many benefits, including cost reduction, less wear on the molding machine, a clearer appearance of the molded product, lighter weight, and less anisotropy. .

Moreover, the composition of the present invention can be produced by a simple method.

Patent applicant: Asahi Kasei Industries, Ltd.

Claims (1)

[Claims] (1) 50 to 99 parts by weight of a polyolefin, 1 to 50 parts by weight of glass fiber based on the polyolefin, 0.1 to 5 parts by weight of an unsaturated silane compound based on 100 parts by weight of the glass fiber, and 0.01 to 5 parts by weight of an unsaturated silane compound. A glass fiber-reinforced polyolefin resin composition obtained by melt-kneading parts by weight of organic carzenic acid or its acid anhydride and 0.005 to 0.5 parts by weight of a radical generator per 100 parts by weight of the polyolefin.