JPH01165657A - Thermoplastic polyester resin composition - Google Patents

Abstract

PURPOSE:To obtain the title composition excellent in heat resistance and impact resistance, by mixing a polyester resin with a polycarbonate resin, a specified graft copolymer, a polyphenylene ether resin and tri(2,3-epoxypropyl) isocyanurate. CONSTITUTION:A graft copolymer (C) is obtained by grafting 70-20wt.% aromatic vinyl monomer (e.g., styrene) and/or methacrylate monomer in the presence of 30-80wt.% rubbery polymer (e.g., polybutadiene rubber). 0.05-3 pts.wt. tri(2,3-epoxypropyl) isocyanurate (E) is added to 100 pts.wt. resin mixture composition comprising 30-70 pts.wt. polyester resin (A) based on a polyalkylene terephthalate, 5-28 pts.wt. polycarbonate resin (B), 5-35 pts.wt. component C and 10-45 pts.wt. polyphenylene ether resin (D) of a reduced viscosity of 0.3-0.7 dl/g as measured in chloroform at 25 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a thermoplastic polyester resin composition that can provide molded articles with excellent heat resistance and impact resistance.

[Problems to be solved by conventional technology and invention]

Thermoplastic polyesters, such as polyalkylene terephthalate, have excellent moldability, mechanical properties, heat resistance stability, weather resistance, electrical insulation properties, etc., and are used in a wide range of fields such as electrical and electronic parts and automobile parts. ing. However, its use is quite limited due to its low rigidity at high temperatures and its low impact resistance, especially notched impact strength.

For example, thermoplastic polyester resin has excellent mechanical properties as an automotive exterior material for online painting.

Application of this material to this purpose has been considered by taking advantage of its thermal properties, but it is currently unusable due to insufficient rigidity and impact resistance at high temperatures. When thermoplastic polyester resin is filled with glass fiber, carbon fiber, wollastonite, etc., rigidity at high temperatures is improved, but impact resistance and surface appearance deteriorate. Although impact resistance is improved by blending a rubber-reinforced resin with a thermoplastic polyester resin, the heat resistance as shown by the modulus of elasticity at high temperatures decreases, making it impossible to withstand online painting. In addition, it cannot currently be used as an automobile exterior panel material because of its large coefficient of linear expansion and noticeable sink marks on the ribs and bosses of molded products.

In addition, in order to improve the moldability of polyphenylene ether resin, it was proposed in Japanese Patent Publication No. 51-21664 to mix polyethylene terephthalate or polybutylene terephthalate.
However, it is not possible to obtain sufficiently satisfactory impact resistance.

The present inventors have proposed a method for improving the elastic modulus, impact resistance, linear expansion coefficient, and dimensional stability of molded products at high temperatures while maintaining the moldability, mechanical properties, etc. of thermoplastic polyester resin. As a result of the study, a resin composition was previously proposed in Japanese Patent Application No. 292,052/1983, which was made by blending a polyphenylene ether resin and a specific graft copolymer in a specific ratio with a polyester resin mainly composed of polyalkylene terephthalate. However, although the impact resistance of such resin compositions has been improved, it does not fully satisfy the high impact level required for automobile outer panels, wheel caps, and the like.

[Means for solving problems]

The present inventors subsequently investigated the iron content for improving the impact resistance of resin compositions consisting of polyester resins, polycarbonate resins, graft copolymers, and polyphenylene ether resins. The present invention was achieved by discovering that the desired objective could be achieved by blending a specific amount of nurate.

That is, the present invention comprises 30 to 70 parts by weight of a polyester resin (A) mainly composed of polyalkylene terephthalate, 5 to 28 parts by weight of a polycarbonate resin (B), an aromatic vinyl monomer and methacrylate in the presence of a rubbery polymer. Acid ester ratio 5 to 35 parts by weight of a graft copolymer (C) obtained by graft polymerizing monomers with a length of 1s or more for the lid and 10 to 45 parts by weight of polyphenylene ether m fat (DJ) (AL (BL) The total amount of components (C) and Q)) is 1
00 parts by weight of the resin mixture composition, IJ (2,
3-epoxypropyl) isocyanurate (E) at 0.
This is a thermoplastic polyester resin composition containing 0.05 to 3 parts by weight.

The polyester resin (A) mainly composed of polyalkylene terephthalate in the present invention mainly has 8 to 22 carbon atoms.
aromatic dicarboxylic acid and an alkylene glycol or cycloalkylene glyconyl or aralkylene glycol having 2 to 22 carbon atoms, optionally containing a minor amount of an aliphatic dicarboxylic acid, such as adipic acid. , sepacic acid, etc. as a structural unit, or may contain polyalkylene glycols such as polyethylene glycol and polytetramethylene glycol as a structural unit. Particularly preferred polyester resins include polyethylene terephthalate, polytetramethylene terephthalate, and the like. These polyester resins may be used alone or in combination of two or more.

The content of the polyester resin (A) mainly composed of the above polyalkylene terephthalate in 100 parts by weight of the resin composition (hereinafter referred to as resin mixed composition) composed of the above components (A) to (D) of the present invention is Weight at 30 to 70 heavy sights,
A content outside this range is undesirable because it tends to make it difficult to obtain the resin composition targeted by the present invention.

The polycarbonate resin (BJ) in the present invention is obtained from dihydroxy diaryl alkane and may be optionally branched. or a diester of carbonic acid. Suitable dihydroxydiarylalkane also includes those having an alkyl group, chlorine atom or bromine atom ortho to the hydroxy group. Preferred specific examples of dihydroxydiarylalkane include 4.4'-dihydroxy-2,2-diphenylpropane (=bisphenol A), tetramethylbisphenol A, and bis-(4-hydroxy7enyl)-p-diisopropylbenzene, etc.
Branched polycarbonates are produced, for example, by substituting a portion of the dihydroxy compound, for example 0.2 to 2 mol %, with polyhydroxy. Specific examples of polyhydroxy compounds include 1,4-bis-(4',4.2'-
dihydroxytriphenolmethyl)-benzene, fluroglucinol, 4,6-dimethyl-2.4.6-tri(4-hydroxyphenyl)-hebutane-2,4j6
-Simethyl-2.4.6-)ly(4-hydroxyphenyl)-hebutane, 1,3.5-)ly(4-hydroxyphenyl)-benzene, 1,1゜1-) IJ
-(4-hydroxyphenyl)-ethane and 2,
Examples include 2-bis(4,4-(4,4'-dihydroxyphenyl)-cyclohexyl)-propane.

The content of the polycarbonate resin (B) in 100 parts by weight of the resin mixture composition is 5 to 283 parts by weight, and if it is less than 5 parts by weight, the impact resistance of the molded article obtained from the resin composition obtained is poor, Moreover, if it exceeds 28 parts by weight, the rigidity at high temperatures tends to decrease, which is not preferable.

The graft copolymer (C) in the present invention is obtained by graft polymerizing one or more monomers of an aromatic vinyl monomer and a methacrylic acid ester monomer in the presence of a rubbery polymer. . As a rubbery polymer, polybutadiene rubber: a copolymer containing 50% by weight or more of butadiene units and a minor amount of styrene units, acrylonitrile units, etc., such as styrene-butadiene copolymer, acrylonitrile-butadiene copolymer Coalescence, etc.: Polyacrylic ester rubber such as polybutyl acrylate: Polyorganosiloxane rubber: Furthermore, polybutadiene/polybutyl acrylate two-stage structure rubbery polymer made by providing polybutadiene with butyl acrylate on the outer layer. or a composite rubber of the above-mentioned rubbery polymer components made of a combination other than the above, or a mixture of 2w1 or more of these. A graft copolymer (C) containing a rubbery polymer content of 30 to 807% by weight is preferably used.

Examples of the aromatic vinyl monomer used in graft polymerization include styrene, α-methylstyrene, and the like. Also, as the methacrylic acid ester monomer, methyl methacrylate,
Examples include ethyl methacrylate. These may be used alone or in combination. In carrying out the present invention, in addition to these aromatic vinyl monomers and methacrylic acid ester monomers, a minor amount of other copolymerizable monomers may be used. Other copolymerizable monomers include acrylic ester monomers such as methyl acrylate and butyl acrylate;
Examples include maleimide monomers such as N-7 dinylene maleimide, and vinyl cyanide monomers such as acrylonitrile and methacrylonitrile.

The amount of the aromatic vinyl monomer, methacrylic acid monomer, and other copolymerizable monomers used in the graft polymerization is 20 to 7 in the graft copolymer (C).
It is used so that it is in the range of 0 weight i%.

Particularly preferred graft copolymers include those in which styrene units are present in the outermost layer. In the case of stepwise graft polymerization, such a graft copolymer can be obtained by grafting a styrene monomer (1-) in the final stage, or by simultaneously craft-polymerizing a mixture containing a styrene monomer.

The above graft polymer (
The content of C) is 5 to 35 parts by weight.

If this content is less than 5 parts by weight, the impact resistance of the molded product obtained from the resulting resin composition will be poor, and if it exceeds 35 parts by weight, the rigidity at high temperatures will tend to decrease, so it is preferable. do not have.

The polyphenylene ether resin 0)) in the present invention has the following formula (wherein R11R1*R8 and R2 are each independently selected from the group consisting of hydrogen, an alkyl group, a halogen, a nitro group, or an amino group, and n is 30 or more.

Preferably the number is 50 or more. ) It is a homopolymer or a copolymer having a repeating unit represented by: - Specific examples of such polyphenylene ether resins include poly(2,6-dimethyl-1,4-phenylene) ether, poly(2,3,6-)dimethyl-1,4-phenylene) ether, and poly(2,6-dimethyl-1,4-phenylene) ether. dinityl-1,4-)unishin)ether, poly(2,6-diprobyl-1,4-)
phenylene) ether, poly(2-methyl-6-ethyl-1,4-phenylene) ether, poly(2-methyl-
6-furopyru-1,4-phenylene)ether, poly(
2-ethyl-6-broby-1,4-phenylene) ether, (2,6-dimethyl-1,4-phenylene) ether and (2,3,6-)dimethyl-1°4-phenylene)
Copolymer with ether, (2゜6-diethyl-1,4-
(phenylene)ether and (2,3,6-)limetheru1
．． copolymer with 4-7 enylene) ether, (2,6-
dimethyl-1,4-phenylene)ether and (2,3,
6-) Copolymers with IJ ethyl-1,4-phenylene) ether and the like. In particular, poly(2,6-dimethyl-1,4-phenylene) ether, poly(2,3,6
-trimethyl-1,4-phenylene)ether and H(2
,6-dimethyl-1,4-7enylene)ether and (2
, 3,6-)dimethyl-1,4-7enylene)ether is preferred.

The degree of polymerization of the polyphenylene ether resin used in the present invention is not particularly limited, but the reduced viscosity at 25°C in a chloroform solvent is 0.3 to 0.7 di/
/ is preferably used. 0.3 di/y
If the reduced viscosity is less than 0.7 di/P, the thermal stability tends to deteriorate, and if the reduced viscosity exceeds 0.7 di/P, the moldability tends to be impaired. These polyphenylene ether resins can be used alone or 21! It is used in a mixture of i or more. Further, in order to improve moldability, the polyphenylene ether resin (D) may contain 40% by weight or less of a polystyrene resin.

The content of the polyphenylene ether resin in 11 parts of 100 ml of the resin mixture composition is 10 to 45 needles.

If this content is less than 10 parts by weight, the effect of improving the rigidity of the molded product from the resulting resin composition at high temperatures will be small, and if it exceeds 45 parts by weight, the impact resistance will tend to be poor, which is undesirable. .

The amount of tri(2,3-epoxypropyl)isocyanuride (E) in the present invention is as follows:
The amount is 0.05 to 3 parts by weight per 00 parts by weight. If this amount is less than 0.05 part by weight, the effect of improving the impact resistance of the resulting resin composition will be small, and if it exceeds 3 parts by weight, the impact resistance will decrease again or the moldability will be poor. This is an undesirable trend.

Tri(2,3-epoxypropyl)isocyanurate)
It was completely unexpected that the blend of (E) showed a remarkable impact strength improvement effect. It is known that dimensional stability can be improved by adding an epoxy compound to polyester resin, but in this case, the effect of improving impact resistance is not observed or is actually reduced, so conventionally The effect was not considered. However, in the present invention, the reason why ly(2,3-epoxypropyl)ine cyanurate exhibits an effect of improving impact resistance is not clear, but the epoxy group in such a compound replaces the methyl group of polyphenylene ether FAfki. This is thought to be because the interaction with other components such as polyester resin changes due to attack and modification.

The thermoplastic polyester resin composition of the present invention is described in (4) above.
-(g)) Components are blended within the above-mentioned content range, and in this case, the content of the above-mentioned polyester resin, which is component (4), in the resin mixed composition is as follows:
The content of the polyphenylene ether resin, which is the component Φ), is always greater than the content of the polyphenylene ether resin in the resin mixture composition, and the polyester resin (N-based phase forms a matrix phase, and the polyphenylene ether resin It is preferred that the ether resin 0)) is dispersed in particulate form, particularly in a uniform particulate form. In addition, the polyphenylene ether resin (D) may also partially form another matrix phase. In order for the polyester resin particles to form a matrix phase, the content of the polyester resin body) in the resin mixture composition must be constantly greater than the content of the polyphenylene ether resin (D) in the resin mixture composition. Just mix it.

Furthermore, if the above conditions are satisfied, a product in which the polyphenylene ether resin (D) is dispersed at least in the form of particles in the polyester resin (4) can be obtained.

Furthermore, there are cases where the polyphenylene ether resin (D) forms another matrix phase, even if only partially.

Further, it is preferable from the viewpoint of physical properties that the graft copolymer (C) is present in the polyphenylene ether resin (D) as a used material. In order for the graft copolymer (C) to exist in the polyphenylene ether resin (D), it is necessary to use a graft copolymer having the above-mentioned styrene units in the outermost layer among the graft copolymers. preferable. In this way, 100 parts by weight of the resin mixture consisting of the components (4) to O)), preferably the polyester resin (4), acts as a matrix, and the polyphenylene ether resin (D) is dispersed in particulate form in this matrix. or at least partially 5 Resin mixture composition 100 forming one matrix phase and in which the graft copolymer (C) is present in the polyphenylene ether resin (D) By blending 0.05 to 3 parts by weight of 2.3-epoxypropyl) isocyanurate (E), impact resistance can be significantly improved while maintaining moldability, mechanical properties, etc. It is something that

The thermoplastic polyester resin composition of the present invention may contain various additives such as flame retardants, modifiers, mold release agents, stabilizers against light or heat, reinforcing fillers, dyes and pigments as necessary. You can also add

Known methods can be used to prepare the thermoplastic polyester resin composition of the present invention, including mixing using equipment such as a Henschel mixer or tumbler that is commonly used for blending resins, followed by a single-screw extruder, It is obtained by melt-mixing using a device commonly used for shaping, such as a twin-screw extruder or an injection molding machine. At this time, in the first stage, polyphenylene ether resin (D) and tri(2,3
- Epoxypropyl) isocyanurate (a mixture whose main component is odor) is melt-kneaded, and then in the second stage, a polyester resin (A), a polycarbonate resin (B), and a graft copolymer (C) are melt-kneaded. This method is preferred because it has a feature that it is more effective in developing impact resistance than a method in which the components are mixed all at once and melt-kneaded.

〔Example〕

The present invention will be explained in more detail with reference to Examples below. In addition, in the following description, "bu" means "'NN county part".

In addition, the following method was used to evaluate each physical property in each Example and Comparative Example.

(1) Izot impact strength Measured according to ASTM D-256 at 23° C. and 50% relative humidity. (Unit Yu・crrL/'crn) (1
(2) Rockwell hardness Measured according to ASTM D-785.

(Unit: R scale) (3) Heat sag test Using a 1/8 inch thick, 1/2 inch wide, 5 inch long specimen, overbank 100I11 at 160℃
A heat sag test was conducted for 1 hour, and the sag (m) of the specimen was measured.

(Unit: Im) The polyphenylene ether resin used in the examples and comparative examples is (2,6-cymethyl-1,4-phenylene)
Niethert (2,3,6-1J mef-1,4-phenylene) is a combination with ether, and 0 at 25°C.
The reduced viscosity (η'p/c) measured with a 1% chloroform solution using an Ubbelohde viscometer was 0.59 di//. The polytetramethylene terephthalate resin used had an intrinsic viscosity [η] of 1.05.

Furthermore, the polycarbonate resin is manufactured by Mitsubishi Chemical Industries, Ltd.
7025A' (trade name) was used.

Reference Example 1 Production of graft copolymer: The solid content in the reaction vessel was 33% by weight, and the average particle size was 0.
63.5 parts (as solid content) of 0.08 μm polybutadiene latex were charged, and to this was added a copolymer latex 1 with an average particle size of 0.08 μm, consisting of 853ii% n-butyl acrylate units and 15 wt% methacrylic acid units.
．． Add 5 parts (as solids) at room temperature with stirring,
After stirring for 30 minutes, an enlarged polybutadiene rubber latex with an average particle diameter of 0.28 μm was obtained. Thereafter, after purging the inside of the reaction vessel with nitrogen, 50 parts of distilled water and 0.2 parts of Demol N (trade name, manufactured by Kao Corporation, naphthalene sulfonic acid formalin condensate) were added to the enlarged polybutadiene latex.
parts, 0.02 parts of sodium hydroxide and 0 parts of dextrose.
．． 35 parts of ferrous sulfate and 0.2 parts of sodium birophosphate were added, and immediately 28 parts of styrene, 7 parts of methyl methacrylate and A mixed solution of 0.2 parts of cumene hydroperoxide was continuously added dropwise over 60 minutes. After finishing dropping 1
The graft polymerization was completed by holding for a certain time. After cooling, the obtained graft copolymer latex was coagulated with dilute sulfuric acid in a conventional manner, washed, filtered, and dried to obtain a graft copolymer.

Example 1 A mixture of 30 parts of polyphenylene ether resin and 0.6 parts of tri(2,3-epoxypropyl)in cyanurate was mixed in a Henschel mixer for 5 minutes, and then 30 m
The mixture was melted and mixed at a cylinder temperature of 300° C. using a yxφ twin-screw extruder and shaped into pellets. Next, 30.6 parts of this obtained resin and 4 parts of polytetramethylene terephthalate resin were added.
0 parts, 15 parts of polycarbonate resin, and 15 parts of graft copolymer were mixed in a Henschel mixer for 5 minutes, and the mixture was heated to a cylinder temperature of 260°C using a 30+mφ twin-screw extruder.
The mixture was mixed by melting and formed into pellets.

After drying the obtained pellets, the cylinder temperature was 260°C.
Various specimens for evaluation were obtained by injection molding at a mold temperature of 80°C.

The evaluation results are shown in Table 1.

Example 2 A mixture of 25 parts of polyphenylene ether resin, 5 parts of polytetramethylene terephthalate, and 1.0 part of tri(2,3-epoxypropyl)in cyanurate was mixed for 5 minutes with a Henschel mixer. The mixture was melt-mixed using a φ twin-screw extruder at a cylinder temperature of 290°C and shaped into pellets. Next, 31 parts of this obtained resin, 45 parts of polytetramethylene terephthalate resin, 10 parts of polycarbonate), and 20 parts of graft copolymer were mixed in a Henschel mixer for 5 minutes, and a mixture was mixed using a 30 muφ twin-screw extruder into a cylinder. The mixture was melted and mixed at a temperature of 260°C and shaped into pellets.

The obtained pellets were molded into various evaluation specimens in the same manner as in Example 1. The evaluation results are shown in Table 1.

Example 3 A mixture of 24 parts of polyphenylene ether resin, 6 parts of polystyrene resin (Nippon Steel Chemical Co., Ltd. #G-15), and 0.3 parts of tri(2,3-epoxyprobyl) isocyanurate was mixed in a Henschel mixer. After mixing for 5 minutes, 30sn
The mixture was supplied from the first supply port of a φ twin-screw press ratio machine, melted and mixed at a cylinder temperature of 280°C, and then from the second supply port, 38 parts of polytetramethylene terephthalate resin and polycarbonate were added to 30.3 parts of the resin mixture. A fixed amount of 17 parts of the resin and 15 parts of the graft copolymer was fed into the second supply port at a ratio of 17 parts, and the whole was melt-mixed and formed into pellets.

After drying the obtained pellets, the cylinder temperature was 260°C.
Various specimens for evaluation were obtained by injection molding at a mold temperature of 80°C.

The evaluation results are shown in Table 1.

Example 4 35 parts of polyphenylene ether resin, 15 parts of polycarbonate resin, 3 parts of polytetramethylene terephthalate resin
5 parts of graft copolymer, 15 parts of graft copolymer, and 0.2 parts of tri(2,3-epoxypropyl) isocyanurate were mixed for 5 minutes using a Henschel mixer, and then the cylinder temperature was adjusted using a 30 nφ twin-screw presser. The mixture was melted and mixed at 260°C and shaped into pellets.

After drying the obtained pellets, the cylinder temperature was 260°C.
Various specimens for evaluation were obtained by injection molding at a mold temperature of 80°C.

The evaluation results are shown in Table 1.

Example 5 38 parts of polytetramethylene terephthalate resin, tri(
A mixture containing 0.3 parts of 2,3-epoxypropyl) incyanurate was mixed for 5 minutes using a Henschel mixer, and then melted and mixed at 240°C using a 30nφ twin-screw presser to form pellets. 38.3 parts of the obtained resin, 17 parts of polycarbonate resin, and 30 parts of polyphenylene ether resin.
5 parts and 15 parts of the graft copolymer in a Henschel mixer.
The mixture mixed for minutes was melt-mixed in one cylinder at a temperature of 260° C. using a 30 snφ twin-screw presser and formed into pellets.

After drying the obtained pellets, the cylinder temperature was 260°C.
Various specimens for evaluation were obtained by injection molding at a mold temperature of 80°C.

The evaluation results are shown in Table 1.

Comparative Example 1 A mixture of 40 parts of polytetramethylene terephthalate resin, 15 parts of polycarbonate resin, 15 parts of graft copolymer, and 30 parts of polyphenylene ether resin was mixed in a Henschel mixer for 5 minutes, and then subjected to a biaxial pressing ratio of 30 mm φ. The mixture was melt-mixed using a machine at a cylinder temperature of 260°C and shaped into pellets.

After drying the obtained pellets, the cylinder temperature was 260°C.
Various specimens for evaluation were obtained by injection molding at a mold temperature of 80°C.

The evaluation results are shown in Table 1.

〔Effect of the invention〕

The resin composition of the present invention exhibits excellent effects such as being able to provide a molded article having high impact strength by having the above-described structure.

Patent applicant: Mitsubishi Rayon Co., Ltd. Agent: Patent Attorney Toshio Yoshizawa

Claims (1)

[Scope of Claims] 30 to 70 parts by weight of polyester resin (A) mainly composed of polyalkylene terephthalate, 5 to 28 parts by weight of polycarbonate resin (B), aromatic vinyl monomer and 5 to 35 parts by weight of (C) and 10 to 45 parts by weight of polyphenylene ether resin (D) to a graft copolymer obtained by graft polymerizing one or more methacrylic acid ester monomers (A) , the total amount of components (B), (C) and (D) is 1
Tri(2,3-
0.05 epoxypropyl isocyanurate (E)
A thermoplastic polyester resin composition containing ~3 parts by weight.