JPS6213450A - Impact-resistant polyphenylene ether resin composition - Google Patents

Abstract

PURPOSE:To provide the title compsn. having excellent impact resistance and mold release characteristics, containing a polyphenylene ether resin, an arom. vinyl hydrocarbon resin and a modified ethylene copolymer compsn. CONSTITUTION:5-95% (by weight; the same applies herein-below) polyphenylene ether obtd. by the oxidative polycondensation of at least one compd. of formula I (wherein R1 is a 1-3C lower alkyl; R2, R3 are each H, R1), 4.5-94.5% arom. vinyl hydrocarbon resin contg. at least 25% structural unit of formula II (wherein R4 is H, lower alkyl; Z is halogen, lower alkyl; P is 0-3) and 0.5-30% modified ethylene copolymer compsn. consisting of 80-40% modified ethylene/alpha- olefin copolymer (a) obtd-by grafting 0.005-5.0% maleic anhydride onto a low- pressure linear low-density ethylene/alpha-olefin copolymer having an MI of 0.5-50 and 20-60% (maleic anhydride-grafted) ethylenically unsaturated group-contg. ester copolymer are blended together.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to (a) polyphenylene ether resin, (b)
An impact-resistant polyphenylene ether resin composition containing a vinyl aromatic hydrocarbon resin and (c) a modified ethylene copolymer composition.

[Conventional technology]

Polyphenylene ether resin is US Patent No. 330687
Specification No. 4, Specification No. 3306875, 5257557
It is a well-known resin disclosed in various known documents such as No. 3257558, No. 4011200, and JP-A-50-126800.

Although polyphenylene ether resin has excellent heat resistance, it requires extrusion and molding at high temperatures. Extrusion and molding at high temperatures lead to deterioration of the polyphenylene ether IV resin, and as a result, the excellent performance inherent to the polyphenylene ether resin is impaired. In addition, the impact strength of polyphenylene ether resin is low and is insufficient for use as is. As a method for simultaneously improving these drawbacks of polyphenylene ether resins, US Pat. No. 5,583,455 discloses a resin composition containing polyphenylene ether and a vinyl aromatic resin. By blending vinyl aromatic resins and polyphenylene ethers, it is possible to reduce the temperatures required for extrusion and molding processes. Further, if a rubber-modified polystyrene resin is used as the vinyl aromatic resin, the impact strength of the resin composition is also improved. Since the rubber content in the composition increases as the proportion of rubber-modified polystyrene increases, the degree of improvement in impact strength also increases, but the improvement in impact strength is still insufficient.

US Pat. No. 3,361,851 discloses a resin composition containing polyphenylene ether and polyolefin. Blending with polyolefins not only improves the impact resistance of polyphenylene ether, but also its solvent resistance and moldability. However, polyphenylene ether and polyolefin do not have good compatibility, so polyolefin can be added at a maximum of 10% by weight based on the entire resin composition.
You can only mix up to Therefore, the degree of improvement in impact strength is not significant.

Japanese Patent Publication No. 56-22544 discloses a resin composition comprising a mixture of polyphenylene ether and a modified olefin polymer obtained by grafting a vinyl aromatic compound onto a polyolefin and having a grafting ratio of 2 to 40% by weight. . Although the compatibility between polyphenylene ether and polyolefin is improved by grafting a vinyl aromatic compound onto a polyolefin, the impact resistance is not sufficiently improved.

In addition, various resin compositions have been proposed as means for improving impact strength. For example, US Patent 56605
Specification No. 51 describes a resin composition containing polyphenylene oxide, polystyrene and rubber; Specification No. 3994856 describes a resin composition containing polyphenylene oxide, polystyrene and an AB-AI type block copolymer; The book contains polyphenylene oxide, polystyrene and rubber, and describes the maximum average diameter of rubber particles dispersed in a resin composition.
No. 4,128,603 describes a resin composition having an ean diameter of 2μ, which contains polyphenylene oxide and high-impact polystyrene, and the high-impact polystyrene contains 22 to 8 QiQ% of elastomer gel particles. Japanese Patent Publication No. 57-8139 discloses a resin composition containing polyphenylene ether, polystyrene, and acrylic resin-modified ABS.

[Purpose of the invention]

It is an object of the present invention to find a polyphenylene ether resin composition with improved impact strength by using components different from those of the conventional compositions described above.

[Summary of the invention]

As a result of intensive studies to achieve the above object, the present inventors found that 1. By modifying the linear, low-density ethylene-α-olefin = Jt = ffi polymer and, in some cases, the ethylene-ethylenically unsaturated group-containing ester copolymer with maleic anhydride, these can be converted into unmodified form. It has been found that impact resistance strength is improved because the compatibility with polyphenylene ether is improved compared to when used in tt.
The objective of the invention has been achieved.

That is, the resin composition of the present invention comprises (a) a polyphenylene ether resin, (b) a vinyl aromatic hydrocarbon resin, and (c) a low-density ethylene-α-olefin copolymer obtained by graft polymerization of maleic anhydride. Impact-resistant polyphenylene ether containing a modified ethylene copolymer composition consisting of ethylene-ethylenic unsaturated group-containing ester copolymer (maleic anhydride graph) f (which may or may not be combined) It is a type resin composition.

The polyphenylene ether resin used as component (a) in the resin composition of the present invention is a monocyclic phenol represented by the general formula (I) (wherein R1 is a lower furkyl group having 1 to 3 carbon atoms, R2 and R3 is a hydrogen atom or a lower alkyl group having 1 to 3 carbon atoms. Polyphenylene ether obtained by oxidative polycondensation of one or more of the following; obtained by graft polymerization of a vinyl aromatic compound to this polyphenylene ether Includes graft copolymers having polyphenylene ether as their backbone. This polyphenylene ether may be a homopolymer or a copolymer.

Examples of the monocyclic phenol represented by the general formula (Il) include 2.6-dimethylphenol, 2゜6-diethylphenol, 2.6-')propylphenol, 2-
Methyl-6-ethylphenol, 2-methyl-6-propylphenol, 2-ethyl-6-propylphenol, m-cresol, 2.3-dimethylphenol, 2.
3-dimethylphenol, 2,3-dipropylphenol, 2-methyl-3-ethylphenol, 2-methyl-
3-propylphenol, 2-ethyl-3-methylphenol, 2-ethyl-3-propylphenol, 2-propyl-3-methylphenol, 2-propyl-3-ethylphenol, 2. S, 6-dolimethylphenol, 2,5.6-doliprobylphenol, 2.6-dimethyl-3-ethylphenol, 2.6-dimethyl-3
-propylphenol and the like. Polyphenylene ethers obtained by polycondensation of one or more of these monocyclic phenols, such as poly(2,6
-Simethyl-1,4-phenylene)ether, poly(
2,6-dinithyl-N4-)unicine) ether, poly<2,6-diprobyl-1,4-phenylene) ether, poly (2-methyl-6-ethyl-1,4-phenylene) ether, poly(2-methyl-6-ethyl-1,4-phenylene) ether, -methyl-6-propyl-1
゜4-phenylene)ether, poly(2-ethyl-6-
Propy/l/-1,4-phenylene)ether, 2.6
-dimethylphenol/2,3.6-)limethylphenol copolymer, 2,6-dimethylphenol/2,5.
6-) Liethylphenol copolymer, 2.6-diethylphenol/2.3.6-) Limethylphenol copolymer, 2.15-dipropylphenol/2.5.
6-) Limethylphenol copolymer, po1+ (2,
6-dimethyl-1,4-phenylene) ether grafted with styrene, 2,6-dimethylphenol/2. 3. 6-) A graft copolymer obtained by graft-polymerizing styrene onto a trimethylphenol copolymer may be mentioned. In particular, poly(2゜6-dimethyl/re-1,4-phenylene)ether, 2,6-dimethylphenol/2.5.6-)limethylphenol copolymer, and styrene graft polymerization to each of the former two. The graft copolymer obtained above is preferable as the polyphenylene ether resin used in the present invention.

The vinyl aromatic hydrocarbon resin used as component (b) in the resin composition of the present invention has the following general formula (厘)-C-CH
2- (In the formula, R4 represents a hydrogen atom or a lower alkyl group, 2 represents a halogen atom or a lower alkyl group, and p is 0 or a positive integer of 1 to 3.) into a polymer thereof. A resin containing at least 25% by weight or more, such as polystyrene, rubber-modified polystyrene (high-impact polystyrene), poly-p-methylstyrene, rubber-modified poly-p-methylstyrene, styrene-phtadiene copolymer, styrene. -butadiene-acrylonitrile copolymer, styrene-acrylic acid rubber acrylonitrile copolymer, styrene-α-methylstyrene copolymer, styrene-butadiene block copolymer, etc., and two or more of these may be used as a mixture.

The modified ethylene copolymer composition used as component (c) in the resin composition of the present invention is (a) a linear, low-density polymer composition manufactured by a low-pressure method with a melt index in the range of 0.5 to 50. o, o in ethylene-α-olefin copolymer
80 to 40% by weight of a modified ethylene-α-olefin copolymer graft-polymerized with os ~ 5.0% by weight of maleic anhydride, and (lyethylene-ethylenically unsaturated group-containing ester copolymer, or the copolymer) It is a composition consisting of 20 to 60% by weight of a copolymer obtained by graft-polymerizing maleic anhydride to ethylene copolymer.The details of this modified ethylene copolymer composition and the manufacturing method are disclosed in JP-A-59-71350. Therefore, it is cited here as a reference regarding the copolymer composition.

Linear, low density ethylene in the copolymer composition
The α-olefin copolymer is polymerized by a low-pressure method using an organometallic catalyst, and has a density of 0.91 to 0.94 t/cc.
It is. The proportion of ethylene is at least 60% by weight, preferably 95-85% by weight. The α-olefin preferably has 3 to 8 carbon atoms, and examples include propylene, butene, hexene, pentene, 4-methylpentene, and the like. The melt index of this copolymer is preferably 0.5 to 50 r/10 minutes as measured according to JIS K-6760.

The ethylene-ethylenically unsaturated group-containing ester copolymer, which is the other main component in the copolymer composition, includes ethylene-ethyl acrylate copolymer, ethylene-ethyl acrylate copolymer,
Examples include ethylene-unsaturated carboxylic acid ester copolymers such as methyl methacrylate copolymers, and ethylene-carboxylic acid vinyl ester copolymers such as ethylene-vinyl acetate copolymers and ethylene-vinyl propionate copolymers. I can do it. Particularly preferred is ethylene-ethyl acrylate copolymer. The melt index of the ethylene-ethylenic unsaturated group-containing ester copolymer is 0.1
~20Of/10 minutes, preferably 0.5~30
f/f 0 minutes. The ester monomer content in the copolymer should be 40% by weight or less, preferably 5 to 25% by weight.

The ratio of the ethylene-ethylenic unsaturated group-containing ester copolymer in the modified ethylene copolymer composition is 20 to 6
It is 0 weight ffi%.

In the modified ethylene-α-olefin copolymer, the proportion of maleic anhydride to be graft-polymerized to the low-density ethylene-α-olefin copolymer is o, oos to 5. 0% by weight, preferably 0.1 to 2.0% by weight. In addition, when using an ethylene-ethylenically unsaturated group-containing ester copolymer modified with maleic anhydride, low-density ethylene-
The total amount of maleic anhydride to be grafted onto the α-olefin copolymer and maleic anhydride to be grafted onto the ethylene-ethylenically unsaturated group-containing ester copolymer relative to the low density ethylene-α-olefin copolymer o,
oos to 5.0% by weight, preferably 0.1 to 2.0% by weight.

The modified ethylene copolymer composition includes: 1) a low-density ethylene-α-ole74 copolymer graft-polymerized with maleic anhydride and an ethylene-ethylenic unsaturated group-containing ester copolymer or a modified copolymer thereof; I) low-density ethylene-α-olefin copolymer, which is mixed mechanically (extruder, hot roll, Banbury mixer 1, etc.) while heating and melting;
It is produced by mechanically mixing an ethylene-ethylenic unsaturated group-containing ester copolymer and maleic anhydride while melting under heating, and a radical initiator may or may not be present. If you adopt the method of
Maleic anhydride also graft-polymerizes to the ethylene-ethylenic unsaturated group-containing ester copolymer.

The proportions of each component (a), (b), and (c) in the resin composition of the present invention are negative) 5 to 95% by weight, (1)) 4.5 to 9
4.5% by weight, (c) 0.5-30% by weight, preferably (a) 10-89% by weight, φ) 10-75% by weight
, (c) There are 1 to 20 weight fkg6 te.

The resin composition of the present invention may further contain an elastomer or other resin as long as the performance of the resin composition of the present invention is not impaired. Elastomer here is an elastomer in the general sense, e.g.
Author: y “Propert 1esand 5tructu
res of Polymers” (JohnWILE
Y & 5ons, Inc., 1960) 71~
The definition adopted on page 78 can be cited, and an elastomer is one with a Young's modulus of 105 to 10'dynes at room temperature.
/cd (9/ci in 0, 1-1020) means theal polymer. Specific examples of elastomers include A-B-
A! A-B-A in which the double bond of the polybutadiene portion of the mold child's last meric block copolymer is hydrogenated! Mold child Lastomeric block copolymer polybutadiene, polyisoprene, copolymer of diene compound and vinyl compound,
Radial teleblock copolymer, nitrile rubber, ethylene-propylene copolymer, radial teleblock copolymer of polystyrene and polybutadiene, said radial teleblock copolymer in which the double bond in the polybutadiene portion is hydrogenated, ethylene- Examples include propylene-diene copolymer (EP-DM), thiol rubber, polysulfide rubber, acrylic acid rubber, polyurethane rubber, graft copolymer of butyl rubber and polyethylene, polyester elastomer, polyamide elastomer, polyurethane elastomer, and the like.

In particular, A-B-A type elastomeric block copolymers and radial teleblock copolymers of polystyrene and polybutadiene are preferred.

In addition to other resins and elastomers, various additives, fillers, etc. can be added to the resin composition of the present invention depending on the purpose.

Specifically, sterically hindered phenols, organic phosphites, phosphonites, phosphonasic acids, cyclic phosphonites, hydrazine derivatives, amine derivatives, carbamate derivatives, thioethers, phosphoric triamides, benzoxazole derivatives, metal sulfides, etc. Stabilizers: UV absorbers such as benzotriazole derivatives, benzophenone derivatives, salicylate derivatives, sterically hindered amines, oxalic acid diamide derivatives, organic nickel complexes; Olefin waxes as lubricants such as polyethylene wax or polypropylene wax; triphenyl Phosphate flame retardant plasticizers represented by phosphate, tricresyl phosphate, cresyl diphenyl phosphate, phosphate obtained from a mixture of isopropyl phenol and phenol, dimer of talesyl diphenyl phosphate; 7'fJ-j lomo Brominated flame retardants represented by biphenyl, pentabromotoluene, decabromo biphenyl ether, brominated polyethylene, etc. Pigments represented by titanium oxide, zinc oxide, carbon black, etc. Glass fiber, glass peas, asbestos, wollastonite , mica, talc, clay, calcium carbonate,
Inorganic fillers such as silica; Metal flakes such as copper, nickel, aluminum, and zinc flakes; Metal fibers such as aluminum fibers, aluminum alloy fibers, brass fibers, and stainless steel fibers; carbon fibers, aromatic Examples include organic fillers typified by group polyamide fibers. The amount of these other components added varies depending on the type of compound used or the purpose of addition.

In preparing the polyphenylene ether resin composition of the present invention, any conventionally known method may be used. For example, after mixing each component with a blender such as a Turnpull mixer or a Henschel mixer, the polyphenylene ether resin composition of the present invention may be prepared using an extruder or a Banbury mixer. A method of kneading with a roll or the like is appropriately selected.

Hereinafter, the resin composition of the present invention will be specifically explained with reference to Examples and Comparative Examples. However, unless otherwise specified, the amount of each constituent component of the resin composition is expressed on a weight basis. ing.

〔Example〕

Example 1 Intrinsic viscosity 0.52 d-g/f (25°C, Chloropho/I/
2,6-dimethylphenol/2°! i, 6
-) IJ methylphenol copolymer (the latter proportion is 5 mol %) 60 parts, impact-resistant polystyrene [(intrinsic viscosity of polystyrene matrix 0.89 d#'r (2
(5°C, in chloroform), gel content 115 wt% (analyzed using methyl ethyl ketone-acetone mixed solvent))
] in the amounts shown in Table 1, with a melt index of 5 and a density of 0.
．． 95 f/cc low density ethylene-α-olefin copolymer (trade name GR3N-7149° Union Carbide) 59.5% by weight, ethylene-ethyl acrylate (melt index: 6, ethyl acrylate:
18%; trade name DPDJ-6169, Nippon Unicar Co., Ltd.) 40% by weight and maleic anhydride 0.5 weight 196 were melted in the presence of 2,5-dimethyl-2,5-(di-tert-butylperoxy)hexane. A modified ethylene copolymer composition obtained by kneading (trade name: rNUC adhesive resin GB301, Nippon Unicar) was mixed with the amounts shown in Table 1, triphenyl phosphate (TPP), titanium oxide, and tetrakis (2,4-difluoride). tert-butylphenyl)-4゜4
Pipe-biphenylene diphosphonite (trade name [P-EP
QJ, Sandoz) and 2.2μmethylene-bis(4-
Methyl-6-tert-butylphenol) (trade name: Antige W-400J Kawaro Chemical) was added to the resin component at 100%
6 parts by weight, 7 parts by weight, 0.4 parts by weight, respectively
Parts by weight and 0.6 parts by weight were thoroughly mixed using a Henschel mixer. The resulting mixture was extruded into pellets using an AS-30 twin-screw extruder (Nakayo Kikai Seisakusho) whose maximum cylinder temperature was set at 290°C, and then into pellets using a 5J-extruder whose maximum cylinder temperature was set at 280°C. Using a 35B injection molding machine (Taki Seisakusho), the injection pressure was 1050 to 9/c.
A test piece (1/8" thick) for measuring Izot impact strength was molded under conditions II.

Notched Izot impact strength was measured using the above test piece. The results are shown in Table 1.

Comparative Example 1 Example 1 was repeated except that the modified ethylene copolymer composition was not used and 740% by weight of high impact polystyrene was used.

The results are shown in Table 1.

As is clear from the results in Table 1, impact resistance strength is improved by using the modified ethylene copolymer composition. Furthermore, the releasability from the mold is improved, and there is no need to use a mold release agent.

Example 2 In the composition of rbJ of Example 1, 35% by weight of high-impact polystyrene was added to 32% by weight of high-impact polystyrene.
wt% and polystyrene-polybutadiene-polystyrene elastomeric block copolymer (weight ratio of polystyrene to polybutadiene moieties is 30/70 and 20% of the copolymer) in luene solution using a Brookfield Model RVT viscometer. Example 1 was repeated except that the solution viscosity measured at 25° C. was 1500 cps; trade name: Kraton TR1101J, Shell Chemical) at 3% by weight. Notched Izot impact strength was 31.3. At the time.../It was a wound.

Example 3 A low density ethylene-α-olefin copolymer (GR5N-7) with a melt index of 5 and a density of 0.93 t/CC
194, powdered maleic anhydride 0.596 (Union Carbide Co.) and a powder in which 4 [1%] of 2,5-dimethyl-2,5-(di-tert-butylperoxy)hexane was adsorbed on calcium carbonate o. Mix OA96 well with a Henschel mixer until the temperature of the cylinder is 180.
Maleic anhydride-grafted ethylene-α-
An olefin copolymer was produced. 60% by weight of the copolymer and ethylene-ethyl acrylate copolymer (melt index 1.5, ethyl acrylate content 15)
%; DPDJ-6182, Nippon Unicar) 40 weight, t9
6 was extruded using an AS-30 twin screw extruder to produce a modified ethylene copolymer composition.

2,6-dimethylphenol/2, used in Example 1
3.6-) Limethylphenol copolymer 42 times! 96
, the amount of high-impact polystyrene used in Example 1 shown in Table 2, the amount of the modified ethylene copolymer composition shown in Table 2, tetrakis (2,4-di-tert-butyiv)
7 Uniw)-4,41-bifuylene diphosphonite and 2,6-di-tert-butyl-p-cresol (trade name: ``Antage BHTJ'', Kawaguchi Chemical) at 0° per 100 parts by weight of the resin component. 4 parts by weight,
0°, and 6 parts by weight were thoroughly mixed using a Henschel mixer. The resulting mixture was heated to a maximum cylinder temperature of 290℃.
It was extruded into pellets using an AS-30 twin-screw extruder set at 280°C, and then the injection pressure was 10°C using a 5J-35B injection molding machine whose maximum cylinder temperature was set at 280°C.
A test piece (thickness: 1/8°) for Izod impact strength measurement was molded under conditions of 50:9/crIl.

Notched Izot impact strength was measured using the above test piece. The results are shown in Table 2.

Comparative Example 2 Example 3 was repeated except that the modified ethylene copolymer composition was not used and 58% by weight of high impact polystyrene was used.

The results are shown in Table 2.

As is clear from the results in Table 2, impact strength is improved by using the modified ethylene copolymer composition. Furthermore, the mold releasability from the mold is improved, and there is no need to use a mold release agent.

Example 4 In the composition of raJ in Example 3, instead of 753% by weight of impact-resistant polymethyl, 750% by weight of impact-resistant polymethyl and a radial teleblock copolymer of polystyrene and polybutadiene (the weight of the styrene component and the butadiene component) were used. Ratio is 50/70; Product name [Turublen T-41
Example 3 was repeated except that 3% by weight of Asahi Kasei Kogyo Co., Ltd.) was used. Izotsu impact strength with notch is 25
, 6 kl-tx/cm.

〔effect〕

Claims (1)

[Claims] (a) polyphenylene ether resin, (b) vinyl aromatic hydrocarbon resin, and (c) low density ethylene-α-olefin copolymer and ethylene-ethylenic unsaturated group-containing ester copolymer obtained by graft polymerization of maleic anhydride. Impact-resistant polyphenylene ether resin composition containing a modified ethylene copolymer composition consisting of a polymer (maleic anhydride may or may not be graft-polymerized)