JPS5996149A - Weather-resistant resin composition having excellent resistance to thermal decomposition - Google Patents

Abstract

PURPOSE:To provide the titled resin compsn. having resistance to thermal decomposition, heat and impact, by blending an alpha-alkylstyrene/acrylonitrile/ acrylate ester copolymer having a specified composition with a non-conjugated diene rubber-reinforced polymer. CONSTITUTION:10-60pts.wt. reinforced polymer (A) obtd. by polymerizing 90- 20wt% two or more compds. selected from an arom. vinyl compd. (e.g. styrene), a vinyl cyanide compd. (e.g. acrylonitrile) and an alkyl unsaturated carboxylate (e.g. methyl acrylate) in the presence of 10-80wt% non-conjugated diene rubber such as ethylene/propylene copolymer rubber, is blended with 90-40pts.wt. copolymer (B) composed of 65-85wt% alpha-alkylstyrene (e.g. alpha-methylstyrene), 10-34.9wt% acrylonitrile and 0.1-5wt% acrylate ester (e.g. methyl acrylate).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a resistant resin composition that has significantly improved thermal decomposition properties and heat resistance during heating during granulation, molding, etc.

Conventionally, so-called ABS resins made of acrylic dinitrile-butadiene-styrene polymers have been widely used in various fields due to their well-balanced physical properties. In fields that require temperature, alpha methyl styrene-acrylonitrile copolymer or alpha methelsunarene-acrylonitrile-methyl methacrylate copolymer? Heat-resistant ABS resins blended with acrylonitrile-butadiene-styrene kraft polymers have met this demand.

All ABS resins, including such heat-resistant ABS resins,
Due to the unsaturated bonds in diene rubber, its weather resistance is extremely poor, limiting its use in outdoor fields.

For this reason, weather-resistant resins using ethylene-propylene copolymers, ethylene-vinyl acetate copolymers, and acrylic dispersion ester copolymers that do not completely blind unsaturated bonds have been developed. Mixtures with other styrenic resins are also known. For example, Japanese Patent Publication No. 42-662 discloses a resin composition consisting of a weather-resistant ABS resin and a styrene resin, which are made by completely graft-polymerizing styrene and acrylonitrile onto an ethylene-propylene rubber.

Weather-resistant ABS resin, like ABS resin, improves C9 heat resistance by fully blending α-methylstyrene-acrylonitrile copolymer, but on the other hand, it easily thermally decomposes during heating during granulation, molding, etc. This causes volatile components to form, forming silver lines on the surface of the molded product, and reducing the heat resistance of the resin itself. It has serious drawbacks such as significantly lowering the amount of money.

As a result of intensive studies on improving the heat resistance and thermal decomposition resistance of weather-resistant fats, the present inventors have found that a specific alpha-alkylstyrene-acrylonitrile-acrylic ester copolymer is added to a non-conjugated diene-based rubber-reinforcing polymer. The present invention was achieved based on the discovery that a weather-resistant resin composition having excellent thermal decomposition resistance, heat resistance, and impact resistance can be obtained by blending the following.

That is, in the present invention, in the presence of a non-conjugated diene rubber, an aromatic vinyl compound, a vinyl cyanide compound, and an unsaturated carboxylic acid alkyl ester compound are selected from
A polymer formed by total polymerization of a compound of 2af or more (A> t
o~60 weight head and alpha alkyl step weight 65~8
Copolymer (B) consisting of 10-34.9% by weight of acrylonitrile and 0.1-5% by weight of acrylic acid ester (B) 90-40% by weight of heat decomposition, heat resistance and impact resistance The weather-resistant resin composition with excellent properties will be explained in more detail.

Polymer (5) gold-containing non-conjugated diene comb used in the present invention includes ethylene-propylene copolymer, non-conjugated diene-Kanakura ethylene-propylene terpolymer of dicyclopentadiene and ethylidenenorbornene, Ethylene-vinyl acetate.

Examples include acrylic acid alkyl ester polymers typified by polyphthyl acrylate, ethylene-propylene copolymers, and ethylene-propylene copolymers.
Propylene-nonconjugated diene copolymers are preferred.

Examples of aromatic vinyl compounds include styrene, α-methylstyrene, dimethylstyrene, vinyltoluene, and the like.

Examples of vinyl cyanide compounds include acrylonitrile, methacrylonitrile, and the like. moreover,
Examples of the unsaturated carboxylic acid alkyl ester include methyl acrylate, ether acrylate, butyl acrylate, methyl methacrylate, ether methacrylate, butyl methacrylate, hydroxyether acrylate, hydroxyether memethacrylate, hydroxyglobil methacrylate, and the like.

There is no limit to the composition ratio of the non-conjugated diene rubber and the total compound in the polymer (4), but the non-conjugated diene rubber 1
It is preferable that the total amount of the compound is 0 to 80% by weight and 90 to 29% by weight. In addition, although there is no particular restriction on the composition ratio of each compound in all compounds, the aromatic vinyl compound
~80 weight attack cyanide vinyl compound fabrication/ma7
t is an unsaturated carboxylic acid alkyl ester compound 50-2
It is preferable that the amount of 0'lE is 0.

In the presence of a non-conjugated diene rubber, two or more compounds selected from these compounds are completely polymerized to form a single polymer (8 is a known polymerization method, such as an emulsion polymerization method).

It can be obtained by suspension polymerization, bath liquid polymerization, or bulk polymerization.

Next, copolymer (B) VC in the present invention will be explained in more detail. Alpha alkyl styrene is a compound represented by the following general formula.

R1-C engineering CH.

(R1 is a C1-C8 alkyl group, R9 is hydrogen,
Required to be a C1-C8 alkyl group or a halogenated alkyl group. ) Alpha methylstyrene, alpha ethyl styrene, methyl alpha methyl styrene are exemplified, but alpha methyl styrene is preferred.

Examples of acrylic esters include phenyl acrylic ester, benzyl acrylic ester, alkyl acrylate (methyl, ethyl, propyl, butyl, amyl and hexyl) ester having an alkyl group having 1 to 6 carbon atoms, etc. Acrylic alkyl esters are preferred, and methyl acrylate is particularly preferred, and not only the composition ratio thereof is also important.

If alpha alkyl styrene is less than 65% by weight or acrylonitrile is more than 34.9% by weight, the heat resistance of the copolymer will be poor;
If the amount of acrylonitrile exceeds 5% by weight or is less than 10% by weight, the polymerization property will deteriorate and this is not preferred for industrial production.

As the amount of acrylic ester increases, the heat decomposition resistance during heating during granulation, molding, etc. is improved, but 5% by weight
If the amount is exceeded, the improvement effect will be small compared to the amount added, and the heat resistance will be poor. On the other hand, when the weight is 0.1%, the heat decomposition resistance is not improved.

Note that ester compounds other than acrylic acid esters, such as meccrylic methyl, do not improve the heat resistance of the copolymer containing a high alpha alkyl styrene content.

There is no restriction on the method for producing the copolymer (B), and for example, the above-mentioned compounds may be used. It can be produced by bulk, emulsion, solution, and suspension polymerization methods using a radical initiator and, if necessary, in the presence of a polymerization degree regulator.

Examples of radical initiators include potassium persulfate, sodium persulfate, ammonium persulfate, and redox compounds of cumene hydroperoxide (N10 to 60 and copolymer CB).

If the weight of the polymer (N is less than 1O), the impact resistance will be poor, and if it exceeds 16,060 weight, the heat resistance will be poor.

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

Examples and Comparative Examples Polymer (A) (■ to ■) Beret and copolymer (B) CG
) to (■) The pellets were kneaded to obtain a resin composition based on the formulation shown in Onbetsu.

The obtained 'fc was molded by injection molding machine using resin composition gold.
At 90℃/! An RA test piece was prepared.

The results of various tests are shown in the table.

The polymers (A) (■ to ■) and the copolymers (B) (■ to ■) used were polymerized based on the following formulations.

Polymer (5) ■ Ethylene-propylene-ethylidene norbornene copolymer (iodine value 8.0, Mooney viscosity 55, propylene content 40% by weight) 200 parts by weight tn-hexane 3
000 parts by weight dissolved in 1500 parts by weight of ethylene dichloride, 300M parts of methylene ref, 150 parts of acrylonitrile.
Parts by weight and 11 parts benzoyl peroxide? In addition, 65℃,
The mixture was stirred in a nitrogen atmosphere for 10 hours. 1. Contact the combined solution with a large excess of methanol, separate the precipitate, and after drying,
Polymer gold obtained.

■ To 450 parts by weight of suspension water containing hydroxyethyl cellulose as a suspending agent, 100 parts by weight of ethylene-propylene-ethylidene norbornene copolymer (Yaw 8.5, Mooney viscosity 61, propylene viscosity 43% by weight), styrene. 80 parts by weight, 50 parts by weight of acrylonitrile, 2.3 parts by weight of initiator, and after stirring at 26°C for 1 hour, the mixture was further heated to 110°C to carry out polymerization. After that, the reactant was cooled to temperature, passed through the mouth, and dried to form a polymer.
Obtained copolymer (B): 300 parts by weight of a monomer mixture containing a loading regulator in a reactor substituted with hydrogen, 0.3 parts by weight of initiator, 2.0 parts by weight of emulsifier, and 140 parts by weight of water. Part holder, heated to 70℃ 01
Time meeting? Inside the reaction system after going? Do not maintain it at 70℃
The monomer mixture of Ap was added continuously over 3 hours, and then polymerized for another 2 hours at 70°C. Polymerization was continued.

After adding a certain amount of antioxidant to the obtained copolymer latex, calcium chloride was filtered and dried, and then granulated using nine pellets. Composition of the obtained Q monomer mixture (parts by weight) ■α-msTY/ACN/EA, t-DM68/
31.510.5 0.4■α-msTY/A
CN, t-DM68/32
0.4 ■α-msTY/ACN/EA, t-DM75/
23/ 2 0.3■α-msTY/AC
N/MA, t-DM75/23/2
0.3 ■α-msTY/ACN/MMA, t
-DM75/23/ 2 0・3■α-m
sTY/ACN, t-DM75/25
0.3 ■α-msTY/ACN/EA, t-0M80/
15/5 0.2■(1-msTY/A
CN/MMA, t-DMso, “is7’ 5
0・2■ α-msTY/ACN
, t-DM80/20
0.2α-mSTY: Alpha methylstyrene ACN: Acrylonitrile EA: Ethyl acrylate MA
: Methyl acrylate MMA : Methyl methacrylate t-DM : t-dodecyl mercaptan Reference example Copolymer B used in the examples for ABS graft polymer
ABS sanitizing and fat composition was prepared and used as a reference example.

The recipe for the ABS graft polymer was as follows: 60 parts by weight of polypumedie/latex (solid content), 200 parts by weight of water, 0.1 part by weight of ethylenediaminetetraacetic acid disodium salt, and ferric sulfate in a reactor purged with nitrogen. o, o o i
parts by weight, 0.4 parts by weight of sodium formaldehyde sulfoxylate. After heating to 60°C, a mixture consisting of 13 parts by weight of acrylonitrile, 27 parts by weight of styrene and 0.2 parts by weight of cumene hydroperoxide was heated for 3 hours. The mixture was coagulated using O 2 calcium chloride which was continuously added and further polymerized at 60° C. for 2 hours, and after filtration and drying, a graft polymer gold was obtained.

Resistance to heat decomposition 1) Pyrolysis due to molding (increase in alpha methyl styrene) The residual alpha methyl styrene in pellets and flat plates was measured by gas chromatography, and the amount of pyrolyzed alpha methyl stenone removed during molding (weight PP) was measured by gas chromatography.
M) '<I asked for it.

11) Weight loss during open pellets) 1 hour during open at 10 °C, and 2
After being left open for 2 hours at 70℃, the difference in weight loss (
Weight loss (%) during treatment at 270°C for 2 hours - ilo°C,
111) Presence or absence of silver wires The presence or absence of silver wires on the surface of the flat plate was observed internally.

patent applicant Sumitomo Naugatuck Co., Ltd.

Claims (1)

[Claims] l) A polymer formed by combining two or more compounds selected from aromatic vinyl compounds, vinyl cyanide compounds and unsaturated carbonaceous alkyl ester compounds in the presence of a non-conjugated diene rubber. Combined (A) 10-60 tungsten buns, 65-85% by weight of alpha alkyl steref, 1 acrylonitrile
0-34.9 Breathability Chio-made acrylic ester 0.1-
A weather-resistant resin composition having excellent heat decomposition resistance, characterized in that it consists of a copolymer consisting of 5% by weight (90 to 40% by weight uniformly). 2) Claims in which the acrylic ester is an alkyl ester of acrylic acid. The weather-resistant resin composition according to item 1. 3) The weather-resistant resin mIM according to claim 2, wherein the acrylic acid alkyl ester is methyl acrylate or acrylic ether, or fc is a mixture thereof.・υ Weather resistance a'I described in item 1 of the scope of patent B'R, in which the non-conjugated diene rubber is an ethylene-propylene copolymer or an ethylene-polymer-non-conjugated diene copolymer
B'i1 composition.