JPS6140345A - Polyolefin composition - Google Patents

Abstract

PURPOSE:To obtain the titled composition having excellent secondary processability, thermal cycling resistance and the falling ball impact strength of the weld part, by compounding a polyolefin with an olefin polymer modified with an unsaturated carboxylic acid. CONSTITUTION:The objective composition can be prepared by mixing (A) 99.9- 50(wt)% polyolefin (e.g. homopolymer or copolymer of ethylene, propylene, etc.) and (B) 0.1-50% unsaturated carboxylic acid-modified olefin polymer composed of (B1) 0.01-20% unsaturated carboxylic acid and/or its anhydride [e.g. dicarboxylic acid (anhydride)], (B2) 99.99-5% olefin (e.g. ethylene, propylene, etc.) and (B3) 0-75% ethylenic unsaturated compound (e.g. olefin, etc.).

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Object of the Invention The present invention relates to a polyolefin composition that is excellent in secondary processability such as paintability and hot stampability, as well as excellent thermal cycleability and drop impact strength of the weld portion.

Polyolefins such as polypropylene and polyethylene have excellent processability and impact resistance, and are inexpensive, so they are used in many fields such as miscellaneous goods, automobile parts, and light electrical parts. Polyolefin compositions with improved dimensional stability and rigidity such as impact resistance or warpage are also widely used by blending rubber-like substances such as Mamaru EPDM, SBR, or inorganic fillers such as glass fiber, Merck, and silica. .

However, polyolefins and polyolefin compositions have poor adhesion when subjected to secondary processing such as painting and hot stamping, and furthermore, their properties against environmental temperature changes are poor.
It has problems such as poor thermal cycling properties) and falling ball impact strength of the weld part.

1 Structure of the Invention The present inventors have conducted intensive research to solve the above-mentioned problems in conventional polyolefins and polyolefin compositions. The present invention was achieved based on the discovery that the ball has excellent properties such as thermal cycling properties, and the falling ball impact strength of the weld portion.

The polyolefin composition of the present invention will be explained in detail below.

0 Polyolefin Examples of the polyolefin used in the present invention include polymers obtained by singly or copolymerizing ethylene, propylene, butene, imbrene, pentene, etc., and block polymers such as π-propylene-ethylene block polymer. Particularly preferred is polypropylene.

Polyolefins can be obtained by known polymerization methods. Note that, in terms of structure, there are two types: isotatic and actuistic, but there is no restriction in the present invention, and either structure can be used. Similarly, there is no limit to the percentage of molecular weight.

0 Unsaturated carboxylic acid-modified olefin polymer The unsaturated carboxylic acid-modified olefin polymer is composed of an unsaturated carboxylic acid and/or its anhydride (1) and an olefin (it) i
Or, there is no limit to the percentage of the composition ratio of the O-unsaturated carboxylic acid-modified olefin polymer, which is a polymer composed of these (i) and (ii) and other ethylenically unsaturated monomers (iii). However, unsaturated carboxylic acids and/or their anhydrides (i
) 0.01-20% by weight, olefin (ii) 99
．． 99-5% by weight and other ethylenically unsaturated monomers Q
ii) 0 to 75% by weight is particularly preferable. Examples of the unsaturated carboxylic acid and/or its anhydride (1) include monocarboxylic acids such as acrylic acid and methacrylic acid;
dicarboxylic acids such as maleic acid, fumaric acid, itaconic acid,
Examples include dicarboxylic anhydrides such as maleic anhydride and itaconic anhydride, with dicarboxylic acids or their anhydrides being particularly preferred.Olefins include ethylene, propylene, butene-
Examples include 1,4 methylpentene-1, and ethylene and propylene are particularly preferred.

In addition, as ethylenically unsaturated ornaments, olefins, vinyl esters containing saturated carboxylic acid components EC2-6, acrylic acid and methacrylic acid esters and maleic esters containing C1-8 saturated alcohol components, Examples include vinyl 10-genides, vinyl ethers, N-vinyl lactams, and carboxylic acid amides.

Unsaturated carboxylic acid-modified olefin polymers can be made in a variety of ways. For example, olefin (11) or olefin (11) and other ethylenically unsaturated monomers 01
1] and an unsaturated carboxylic acid and/or its anhydride (1) are mixed and heated.

0 Polyolefin Composition The polyolefin composition of the present invention is composed of the above-mentioned polyolefin and an unsaturated carboxylic acid-modified olefin polymer. Although there is no particular restriction on the composition ratio of each polymer, it satisfies the objectives of the present invention and From the viewpoint of processability of the final composition, it is preferable that the polyolefin content be 99.9 to 50% by weight and the unsaturated carboxylic acid-modified olefin polymer be 0.1 to 50% by weight.

Furthermore, the mixing method includes a known mixing method using a Banbury mixer, a single-screw extruder, a twin-screw extruder having a cross-wire block, and the like.

In addition, when mixing the polyolefin and the unsaturated carboxylic acid-modified olefin polymer, filling with rubber-like polymers such as EPDM, SBR, glass fiber, Merck, silica, asbestos, silicate, titanium oxide, graphite, molybdenum sulfide, etc. agents, known dyes and pigments, stabilizers, plasticizers, antistatic agents,
It is also possible to add ultraviolet absorbers, lubricants, etc.

The present invention will be specifically explained below using examples, but the present invention is not limited to these in any way.

< *1 Noprene W-100 manufactured by Sumitomo Chemical Co., Ltd. *2 “Noprene AW-564” manufactured by Sumitomo Chemical Co., Ltd. *3 Urethane paint “R-263” manufactured by Nippon Bee Chemical Co., Ltd. (without primer) applied to all test pieces, Drying.10 horizontal and vertical marks on the coating film.
A cut was made in the book and a peel test was performed using adhesive tape.
Peeling of 10/'1oo' or more was considered defective.

*4 Real stamp the aluminum wheel on the test piece (2
00°C, 3kg/crl, 3 seconds), 10 pieces of Vc each on the upper and lower sides of the aluminum wheel were inserted, and a peel test was performed using adhesive tape. .

*5 Cylindrical metal with an inner diameter of 30 mm and a height of 50 mm (thickness 1
Insert molded using m+n) k, inner diameter 27.
A molded product with a diameter of 5 mm, an outer diameter of 33.5 m+n, and a height of 50 m was created.

23℃ x 2 hours → 80℃ x 2 hours → 23℃ x 2 hours → -
Test f: 1 cycle of 30°C x 2 hours → 23°C x 2 hours: Perform 4 cycles and observe the entire surface of the molded product after the test,
Items with cracks, etc. were considered defective.

*6 Two gates with a gate interval of 100mm (2 and 5 gates each)
X 2. Ortan) from molten resin (230℃)
A test piece with a thickness of 3wn and 150 gourds each in the vertical and horizontal directions was prepared.

Place the test piece in a jig (height 80rrrm, inner diameter 120yo+.

(Outer diameter: 126 rrrm) and heat at -30°C.
A 1# steel ball is dropped from the center (weld part) of the test piece in a cold room adjusted to , and the maximum energy value (kg·cm ) at which the test piece does not break is determined.

Effects of the Invention A polyolefin composition containing an unsaturated carboxylic acid-modified olefin polymer has significantly superior secondary processability, thermal cyclability, and falling ball impact strength (weld portion) compared to polyolefins.

Claims (1)

[Scope of Claims] 1) A polyolefin composition comprising a polyolefin and an unsaturated carboxylic acid-modified olefin polymer. 2) The polyolefin composition according to claim 1, wherein the polyolefin is 99.9 to 50% by weight and the unsaturated carboxylic acid-modified olefin polymer is 0.1 to 50% by weight.