JPS63205346A - Resin composition - Google Patents

Abstract

PURPOSE:To obtain a resin composition excellent in heat resistance, mechanical strengths, weathering resistance, oil resistance, etc., by mixing a polyphenylene ether resin with a specified polyalkylene terephthalate graft polymer prepared by a macromonomer process. CONSTITUTION:A graft polymer in which the branch component is vinyl polymer segment compatible with a polyphenylene ether resin and the trunk component is a polyalkylene terephthalate is produced by a macromonomer process. the obtained polylkylene terephthalate graft polymer is mixed with a polyphenylene ether resin to obtain the purpose resin composition. In this way, it is possible to easily mix the polyalkylene terephthalate resin difficultly compatible with the polyphenylene ether resin and to obtain a resin composition provided with the merits of both.

Description

Detailed Description of the Invention (a) Purpose of the Invention [Field of Industrial Application] The present invention relates to a resin composition that is used in a wide range of applications, both for general consumption and industrial use. This invention relates to a resin composition consisting of a polyphenylene ether resin and a grafted polyalkylene terephthalate resin, which has recently attracted particular attention as an engineering plastic with advanced physical properties.

In addition, the polyphenylene ether resin in the present invention is a resin consisting only of phenylene ether units or having this as the main unit, or a resin composition having this resin as the main component, and the polyalkylene terephthalate resin is It is a resin consisting only of alkylene terephthalate units or having alkylene terephthalate units as its main unit, or a resin composition having this resin as its main component.

[Prior art and its problems]

BACKGROUND OF THE INVENTION With the remarkable development of the polymer chemical industry in recent years, many polymer materials are being used in large quantities in daily life products, industrial products, vehicle parts, building materials, and the like.

Particularly after the oil crisis, the need for higher performance and higher functionality of products has increased, and even in the field of polymer materials, engineering plastics have shown remarkable growth potential, showing that consumer trends are also showing signs of the times. Can be done. Under these circumstances, even in the field of conventional plastics, efforts are being made to improve and modify them in various ways in order to meet the diversifying demands of the market.

Polyphenylene ether has excellent mechanical properties, thermal properties, electrical properties, dimensional stability, light weight, etc., and is one of the engineering plastics that has attracted much attention in recent years.However, when used alone, it has remarkable moldability. Since it is bad and expensive, it is usually used as an alloy with polystyrene resin, which has good compatibility. This polymer alloy is manufactured by General Electric Company in the United States under the trade name Noryl.
It is generally available under the trade name Zylon, a product of Asahi Kasei ■, and is attracting attention as a resin with growth properties. In particular, the growth in consumption over the past few years has been outstanding compared to other engineering plastics, and they are used in applications where general-purpose plastics cannot meet performance requirements, such as automobile interior materials and office equipment. . However, the uses of polyphenylene ether are often limited due to drawbacks inherent to its properties, such as high melt viscosity, poor oil resistance, and poor weather resistance.

On the other hand, polyalkylene terephthalate is widely used as a synthetic fiber along with nylon and acrylic, but recently it has also been consumed in large quantities as a film and molding material. For example, polybutylene terephthalate (hereinafter referred to as PB
Demand for polyphenylene ether (sometimes abbreviated as T) has increased in recent years as a new general-purpose engineering plastic, along with polyphenylene ether, and it is expected to maintain high growth potential in the future. PBT has various desirable properties as a crystalline engineering plastic, such as heat resistance,
It has weather resistance, mechanical strength, oil resistance, chemical resistance, etc.

On the other hand, poor dimensional stability due to high molding shrinkage rate,
There are problems with impact resistance, alkali resistance, paintability, adhesion, etc., and efforts are being made to overcome these problems. In particular, in order to improve heat resistance and strength, composites are generally made by adding glass fibers. However, even in this case, new problems such as wear of the kneading machine, warping of the molded product, and anisotropy of strength have arisen. In addition to synthetic fibers that have traditionally been consumed in large quantities, polyethylene terephthalate (hereinafter sometimes abbreviated as PET) has recently been in demand for blow molded products such as bottles and molding materials reinforced with glass fiber. It is expected that it will continue to grow as a general-purpose engineering plastic along with polybutylene terephthalate. Like PBT, PET has both advantages and disadvantages as a crystalline engineering plastic, but in particular, poor moldability and poor dimensional stability due to slow crystallization rate are problems.

As described above, polyphenylene ether and polyalkylene terephthalate have contradictory properties in many respects, and both have the characteristics of a non-grade resin and a crystalline resin, so by blending the two, the properties of both can be balanced. Technological orientation to develop practical resin compositions has begun to attract attention.

Polymer blending is a method that has recently been attracting attention as a method of improving and modifying existing resins to suit diversifying uses.By mixing different polymers, it is possible to take advantage of the characteristics of the resin and eliminate its shortcomings. This complementary method can flexibly respond to the diversifying needs of resin users, avoid wasting resources due to excessive quality, and reduce the investment burden that is inevitable in the research and development of new resins. It has the advantage of being able to

Attempts to use polymer alloys or blends have been made for a long time, but due to the recent diversification of market needs and the need to conserve resources and energy, they have recently become more popular, especially in the field of engineering plastics.

Several inventions have been proposed for resin compositions made of blends of polyphenylene ether and polybutylene terephthalate or other polyesters, although the number is not large. For example, a proposal was made to blend polyester with the purpose of improving the moldability of polyphenylene ether to obtain a composition with excellent moldability, self-lubricity, and stress crack resistance (Japanese Patent Laid-Open No. 49-50050); A proposal was made to blend polyphenylene ether with the aim of improving the heat resistance of polybutylene terephthalate to obtain a composition with a high heat distortion temperature and excellent strength (JP-A-49-756).
62 Publication), polyphenylene ether/polyethylene blended for the purpose of improving the moldability and kneading stability of polyphenylene ether and the heat resistance and dimensional stability of polyethylene terephthalate (Japanese Unexamined Patent Publication No. 159847/1984), polyphenylene ether/polyethylene An example in which thermal stability was improved by adding a small amount of polystyrene resin to a terephthalate blend (Japanese Patent Application Laid-Open No. 174645/1984), and a small amount of polyester with a special structure added to a polyalkylene terephthalate/polyphenylene ether blend There are examples (Japanese Unexamined Patent Publication No. 60-94450) that show improved physical properties.

When blending different types of polymers, the most important thing is how to mix and mix the polymers, which are inherently poor in compatibility. Because the values of , the combination is inherently poor in compatibility, simply blending would result in a composition with extremely poor physical properties that would be impractical. The first two inventions mentioned above solve this problem by limiting the proportion of the blend, and the second one solves this problem by focusing on physical properties other than mechanical strength. states the advantages of The latter two use polystyrene resin or polyester with a special structure as the third component, but considering their molecular structure, it is difficult to imagine that these polymers will function as effective compatibilizers, so their effectiveness remains unclear. would be limited.

Generally, methods for improving the miscibility of incompatible polymer blends include using a compatibilizing agent, and modifying one or both components of the blended resin by a method such as grafting to increase compatibility. However, as a grafting reaction to polyphenylene ether, grafting of vinyl polymerizable monomers utilizing the radical sensitivity of this resin is known, but It is impossible to graft. On the other hand, as a grafting reaction to polyalkylene terephthalate, chain transfer method using peroxide, radiation grafting method, polymer initiator method, etc. can be considered, but these methods have extremely low grafting efficiency and require control of molecular weight and composition. is also impossible.

Therefore, if the grafting reaction or the production of graft polymers for improving the compatibility of resins to be blended can be synthesized inexpensively and easily, and the molecular structure, composition, molecular weight, etc. can be controlled as desired, it would be possible to do so. The technical and economic value would be enormous.

(B) Structure of the Invention [Means for Solving the Problems] In consideration of the problems of the prior art as described above, the present inventors have made efforts to obtain a resin composition with excellent performance. As a result of our investigation, we found that when blending polyphenylene ether resin and polyalkylene terephthalate resin, we decided to introduce a segment that is compatible with polyphenylene ether as polyalkylene terephthalate resin in order to obtain a resin composition with improved miscibility. The present invention was completed based on the discovery that the performance of the resin composition was improved by using a polyalkylene-based graft polymer produced by the above method, and by using a macromonomer graft polymer as the graft polymer.

That is, the present invention provides polyphenylene ether resin (A),
and a graft polymer (B) produced by a macromonomer method having a vinyl polymer segment compatible with the resin (A) as a branch component and a polyalkylene terephthalate segment as a trunk component, the graft polymer (B)
This is a resin composition that does not contain any other polyalkylene terephthalate resin.

[Graft polymer produced by macromonomer method] In the present invention, the graft polymer produced by macromonomer method (hereinafter simply referred to as graft polymer) means a polyalkylene terephthalate-based graft polymer produced using a macromonomer.

Such a method for producing a graft polymer using a macromonomer method has the following features: ri) The amount of the polymer to be a backbone component existing as a non-grafted polymer is small.

ii) The molecular weight of the branch components, the molecular weight of the entire graft polymer, and the ratio of branches to trunk can be easily controlled.

iii) Combinations of branch components and trunk components can be freely selected depending on the purpose. It has been attracting a lot of attention recently because it can easily obtain high-performance graft polymers that cannot be obtained by conventional methods.

The graft polymer in the present invention has the following molecular structure:
It is a graft polymer having a vinyl polymer segment compatible with polyphenylene ether derived from a macromonomer as a branch component and a polyalkylene segment as a trunk component.

Examples of the vinyl polymer segment which is a branch component include a segment consisting of a homopolymer or copolymer having a styrene monomer unit as a main unit, as described in detail in the macromonomer section below.

On the other hand, examples of the polyalkylene terephthalate segment which is the backbone component include a segment made of polyester whose main component is polyalkylene terephthalate obtained by polycondensing terephthalic acid or its lower alcohol ester with various diols. The diols include ethylene glycol, propylene glycol, 1.4
- Aliphatic, alicyclic, and aromatic diols such as -7'tanediol, hexamethylene glycol, neopentyl glycol, diethylene glycol, cyclohexane dimetatool, and bisphenol A, and preferred ones include ethylene glycol. and 1,4-butanediol. Diols may be used alone or in combination of two or more.

Note that the segment made of the polyester containing polyalkylene terephthalate as a main component contains acid components other than terephthalic acid, such as isophthalic acid, oxybenzoic acid, diphenylmethane dicarboxylic acid, naphthalene dicarboxylic acid, adipic acid, and sebacic acid. It may contain a small amount of units consisting of an acid component such as or its lower alkyl ester, and the amount is based on the total amount of acid component units,
The content is preferably 10% by weight or less.

Furthermore, the segment made of polyester is made of a trifunctional or higher-functional polycarboxylic acid, an alkyl polycarboxylate, a polyhydric alcohol, etc. that can be used in polycondensation for the purpose of increasing the molecular weight of the segment. The unit may be contained in a small amount, and the amount is determined based on the overall view of the unit consisting of polyester forming components other than the macromonomer.
The content is preferably 5% by weight or less.

In the present invention, the composition of the vinyl polymer segment which is the branch component of the graft polymer and the polyester segment which is the trunk component is 0.5/99.5 to 50150 in weight ratio.
The range is preferably 1/99 to 30/70, more preferably 2/98 to 20/80. If the proportion of the vinyl polymer segment is less than 0.5% by weight, the graft polymer will essentially become a polymer of polyalkylene thirefrate alone, and the effect of grafting the vinyl polymer cannot be expected, which is undesirable. If the proportion of segments exceeds 50%, it is not preferable because the molecular weight of the graft polymer is difficult to increase (and the physical properties of the composition obtained by blending with polyphenylene ether are deteriorated).

The graft polymer in the present invention can be produced in the same manner as known polyester production methods.

- For example, when synthesizing polyester from monomers by the melt polycondensation method, a predetermined amount of dibasic acid and/or
Alternatively, the dibasic acid diester and diol are further added with the following macromonomers and catalysts, heated to 150 to 200°C to esterify, and then heated under reduced pressure to distill off the diol present in an equivalent amount or more relative to the acid. Graft polymers can be easily obtained by polycondensation at ~280°C for several hours.

Conventionally known catalysts include Ca, Mgs, Zn, and Cd.
, Ti, Ge, Sn, Pb, Sb, Mn,
Compounds such as Co and Zr may be used, and a phosphite ester may be added as a stabilizer.

In addition to melt polycondensation at high temperatures as described above, graft polymers may be produced by solution polycondensation or interfacial polycondensation at low temperatures, or by solid phase polymerization to further increase the molecular weight. good. The method and conditions for producing the graft polymer in the present invention may be appropriately selected depending on the type of the intended graft polymer and the intended use.

[Macromonomer]

The macromonomer used in the present invention is a polycondensable polymer having a functional group capable of polycondensation at one end of the molecular chain, which is composed of a relatively low molecular weight vinyl polymer that is compatible with polyphenylene ether resin. . The terminal structure of the macromonomer in the present invention includes a carboxyl group,
2 carboxylic acid ester groups or hydroxyl groups each
The unique terminal structure can be cited as a typical example, but
In addition to these, amino groups and the like can be mentioned.

Examples of the terminal structure each having two carboxyl groups, carboxylic acid diester groups, or hydroxyl groups include -CH-C00H -CH-COOR -CH2CH-〇H. In the above formula (II), R is suitably a straight chain or branched alkyl group having 10 or less carbon atoms.

In addition, the vinyl polymer portion forming the skeleton of the macromonomer in the present invention is composed of one unit of a radically polymerizable vinyl monomer, and the polymer is compatible with polyphenylene ether resin, and a specific example is styrene. Examples include homopolymers consisting of monomer units or styrene derivative monomer units, and copolymers consisting of styrene monomer units or styrene derivative monomer units as the main unit and other copolymerizable monomer units. It will be done.

Suitable examples of the copolymerizable monomer unit include acrylic ester monomer units, methacrylic ester monomer units, acrylonitrile monomer units, and methacrylonitrile monomer units. The content of the copolymerizable units in the skeleton is suitably 20 to 0% by weight based on the total amount of all monomer units.

The molecular weight of the macromonomer in the present invention may be within a range that does not impair the polymerizability of the produced macromonomer, and the number average molecular weight is suitably 1,000 to 20,000, preferably 2,000 to 15,000. A macromonomer with a number average molecular weight of less than 1,000 is undesirable because the degree of polymerization as a single polymer unit is too low, and the physical properties of the macromonomer are not reflected in the graft polymer obtained using the macromonomer.
Exceeding this is not preferable because it tends to cause problems such as a decrease in polycondensation properties during the production of the graft polymer and a tendency to cause phase separation in the reaction system.

The number average molecular weight of the macromonomer is a polystyrene equivalent number average molecular weight measured by gel permeation chromatography (hereinafter referred to as GPC), and the measurement conditions are as follows.

Equipment: High performance liquid chromatography (e.g. Toyo Soda Kogyo ■Product name HLC-802UR) Column: Polystyrene gel (e.g. Toyo Soda Kogyo ■Product name G4000H
8 and G3000H8) Elution solvent: Tetrahydrofuran Efflux rate: 1. Oml/min Column temperature: 40°C Detector: RI detector As an example of the method for producing the macromonomer of the present invention, radical polymerization is performed in the presence of a chain transfer agent corresponding to the terminal structure into which the radically polymerizable monomer is desired to be introduced. Here are some ways to do it. As the chain transfer agent used in the above method, mercaptan compounds are preferred because they have an appropriate chain transfer constant, and thiomalic acid is suitable for macromonomers having two carboxyl groups at the terminals. Specific examples of the compound include dimethyl thiomalate for macromonomers having two carboxylic acid ester groups at the ends, and thioglycerin for macromonomers having two hydroxyl groups at the ends.

Furthermore, as the polymerization method, any of solution polymerization, bulk polymerization, emulsion polymerization, and suspension polymerization can be used in the presence or absence of a conventionally known radical polymerization initiator. The mercaptan chain transfer agent has a high solubility in water, and in emulsion polymerization and suspension polymerization conducted in an aqueous medium, most of the chain transfer agent exists in the medium and works to control polymerization. A solution polymerization method or a bulk polymerization method is preferred since it is difficult to obtain a macromonomer having a desired molecular weight due to an insufficient amount of chain transfer agent.

According to the above method, a macromonomer can be obtained by a single-stage polymerization reaction, but it is also possible to synthesize a macromonomer by a two-stage reaction of polymerization (first stage) and end group introduction reaction (second stage). In this case, a functional group is introduced at the end of the polymer by using a known mercaptan chain transfer agent containing one functional group in the form of a carboxyl group or a hydroxyl group in the first stage of polymerization. A terminal structure that can be polycondensed in the second stage reaction may be formed as a scaffold.

[Polyphenylene ether resin]

As the polyphenylene ether resin used in the present invention, a polyphenylene ether resin commercially available as a polymer alloy of polyphenylene ether and a polystyrene resin can be used, or polyphenylene ether itself without a polymer alloy can be used. It's okay.

The polyphenylene ether used in the present invention can be prepared by reacting phenol with oxygen in the presence of a copper complex catalyst, as described in a number of publications including U.S. Pat. Nos. 3,306,874 and 3,306,875. Can be done.

Preferred polyphenylene ethers in the present invention are those represented by the following general formula.

where the oxygen ether atom of one unit is connected to the phenyl nucleus of the next adjacent unit, n is a positive integer of at least 5
0, and Q is a hydrogen atom, a halogen atom, a hydrocarbon group not containing a tertiary carbon atom in the α position, a halogenated hydrocarbon group or an alkoxy group having at least two carbon atoms between the halogen atom and the phenyl nucleus. Indicates a substituent selected from the group consisting of.

More preferred polyphenylene ethers are those in which Q is an alkyl group, and even more preferred are polyphenylene ethers having 1 carbon number.
-4 alkyl groups, and the most preferred polyphenylene ether is bosu(2,6-cymethyl-1
．． 4-phenylene) ether.

The polyphenylene ether resin used in the present invention includes a block copolymer such as a styrene-butadiene block copolymer as an impact strength enhancer, or various rubber resins such as ethylene-vinyl acetate copolymer, ethylene-propylene - Diene monomer - A small amount of terpolymer, ethylene-ethyl acrylate copolymer, styrene-butadiene random copolymer, etc. may be contained, and the amount thereof is 20 times or less based on the polyphenylene ether resin. It is preferable to do so.

In addition, the polyphenylene ether resin in the present invention is
A small amount of resin additives such as flame retardants, ultraviolet absorbers, lubricants, stabilizers, and antistatic agents may be included, and the amount thereof is preferably 20% by weight or less based on the polyphenylene ether resin.

[Production method of resin composition]

The resin composition of the present invention comprises a polyphenylene ether resin (A) and a vinyl polymer segment compatible with the resin (A) as branch components, and a polyalkylene terephthalate segment as a backbone component, which is grafted by a macromonomer method. A resin composition consisting of a polymer (B),
The blending ratio of resin (A) and graft polymer (B) is
Resin (A) 5 to 95 parts by weight, graft polymer (B) 9
5 to 5 parts by weight is suitable.

If the polyphenylene ether resin or graft polymer is less than 5 parts by weight, the properties of the resin will not be reflected in the physical properties of the resin composition, which is not preferable.

The resin composition of the present invention can be easily obtained by melt-kneading a polyphenylene ether resin and a graft polymer using a conventional blending method such as an extruder, kneader, open roll, etc. A preferred method for obtaining the resin composition is to mix using a Henschel mixer or the like, heat, melt-knead, and extrude using an extruder or the like, and then cut the resin composition into pellets.

The pellet-shaped resin composition thus obtained can be molded into a desired shape by, for example, injection molding, press molding, extrusion molding, blow molding, or the like.

The resin composition of the present invention may contain well-known additives such as plasticizers, pigments, flame retardants, reinforcing fibers such as glass fibers and carbon fibers, inorganic/organic fillers, and stabilizers.

[Effect]

In the present invention, due to the action of the vinyl polymer segment that is compatible with the polyphenylene ether resin, which is a branch component of the polyalkylene terephthalate graft polymer, the resulting resin composition can be mixed with the polyphenylene ether resin in the molded product. It is possible to disperse the alkylene terephthalate resin to an extremely microscopic phase separation, and it is also possible to firmly bond two different types of polymers at the phase interface.

The present invention will be described in more detail below with reference to Reference Examples, Examples, and Comparative Examples. All percentages listed on each side are by weight.
and parts mean parts by weight.

Reference Example 1 Production of a macromonomer having a styrene polymer skeleton and two methyl ester groups at one end (hereinafter referred to as one-end dimethyl ester type styrene macromonomer) Stirrer, reflux condenser, dropping funnel, and temperature A glass flask equipped with a meter was charged with 333 parts of styrene and 2.67 parts of dimethyl thiomalate, and a mixture of 667 parts of styrene and 12.46 parts of dimethyl thiomalate was placed in the dropping funnel. The flask was heated to an elevated temperature to reflux the contents. The solution in the dropping funnel was added dropwise thereto over 4 hours. Thereafter, 2.67 parts of dimethyl thiomalate was added in portions of 1/12th part at 15 minute intervals.

After the completion of the split preparation, the mixture was further aged for 2 hours. The polymerization conversion rate of styrene was 96.4%. Thereafter, the pressure of the reaction system was reduced to remove residual monomers, yielding 961 parts of a solid one-end dimethyl ester type styrene macromonomer. During this time, the reaction temperature gradually increased from the initial reflux temperature of 146°C, and was kept constant when it reached 160°C. GP
The average molecular weight of the Mac0 monomer determined by C is M
n=10,000, Mw=23.400 and Mw
/ M n =2.34.

Reference Example 2 Production of polybutylene terephthalate-polystyrene graft polymer ■ 251.3 parts of dimethyl terephthalate and 1,4-butanediol were placed in a separable flask equipped with a stirrer, reflux condenser, temperature system, and nitrogen gas inlet. 256.
5 parts, 15.0 parts of the one-terminated dimethyl ester type styrene macromonomer produced in Reference Example 1, and 0.30 parts of tetrabutyl titanate were charged, and methanol produced by the transesterification reaction was removed by heating and raising the temperature under a nitrogen stream. I reacted while doing so.

During this time, the reaction temperature rose from 150'C to 200°C.

Thereafter, the temperature of the reaction system was raised, and at the same time the pressure was reduced to distill out 1,4-butanediol while reducing the internal pressure to 5.
mm Hg or less. The reaction solution was heated to 270°C,
Polycondensation was carried out for 2 hours while distilling off 1,4-butanediol. During the reaction, the pressure within the system reached 0.6 mm6g. After the reaction, nitrogen was introduced to return the pressure to normal pressure, and the resulting high viscosity liquid of the graft polymer was taken out. 240°C of this, 2
, 16, the melt flow index under load is 8
．． 8 (g/10 minutes).

Reference Example 3 Production of polybutylene terephthalate-polystyrene graft polymer ■ 238.1 parts of dimethyl terephthalate and 1.4-butanediol were placed in a separable flask equipped with a stirrer, reflux condenser, temperature system, and nitrogen gas inlet. 243.
0 parts, 30.0 parts of the one-end dimethyl ester type styrene macromonomer produced in Reference Example 1, and 0.30 parts of tetrabutyl titanate were heated under a nitrogen stream to raise the temperature and remove the distilled methanol. A transesterification reaction was carried out. During this time, the reaction temperature is 150°C to 200°C.
It rose to Thereafter, the temperature of the reaction system was raised, and at the same time the pressure was reduced to distill out 1,4-butanediol, while the internal pressure was brought to 5+nmHg or less over about 30 minutes. Heat the reaction solution to 270″C
Polycondensation was carried out for 2 hours while distilling off 1,4-butanediol. The pressure within the reaction thread reached 0.5 n+m Hg. After the reaction, nitrogen was introduced to return the pressure to normal pressure, and the resulting high viscosity liquid of the graft polymer was taken out. The melt flow index of this product was 26.6 (g/10 minutes) at 240°C and 22,16 kg tJ.

Example 1 Commercially available polyphenylene ether resin (manufactured by Engineering Plastics, trade name Noryl 534J) 2
37 parts and 263 parts of the graft polymer (polystyrene composition 5%) produced in Reference Example 2 were added to a twin screw extruder (vent type, co-rotating, diameter 29 mm, L/D = 25
) at a resin temperature of 283° C. The resulting strand was cooled and then cut to obtain a pellet-shaped resin composition. Appearance of the resulting resin composition pellets (whether the surface is smooth or not), melt flow index (at 275°C under a load of 16 kg), tensile strength and elongation at break (pressing the resin composition pellets at 290"C) A dumbbell-shaped test piece was created from the sheet obtained by molding, and the tensile speed was 5 mm/mi according to JIS K7113.
n,) and impact strength (instead of the above dumbbell-shaped test piece, an impact test piece without a notch was prepared in the same manner and carried out using a Charpy impact tester in accordance with JIS K7111). . Further, the test piece was cooled with liquid nitrogen and then crushed, and the fractured surface was observed with a scanning electron microscope to measure the particle size of the dispersed different polymer. These results are shown in Table-1.

Example 2 222 parts of polyphenylene ether resin (manufactured by Engineering Brushtics ■, trade name Noryl 534J) and 278 parts of the 10% polystyrene composition prepared in Reference Example 3 as a graft polymer were mixed in the same manner as in Example 1. They were melt blended and subjected to similar physical property tests. The results are shown in Table-1.

Comparative Example 250 parts of polyphenylene ether resin (manufactured by Engineering Brushtics ■, trade name Noryl 534J) and 250 parts of polybutylene terephthalate (manufactured by Toshi ■, trade name PBT1401) were mixed in the same manner as in Example 1. The materials were melt-blended and subjected to similar physical property tests. The results are shown in Table-1.

(c) Effects of the invention A resin composition made of a polyphenylene ether resin and a polyalkylene terephthalate resin by blending in the prior art had a problem in miscibility, but according to the present invention, as a polyalkylene terephthalate resin, polyphenylene By using a polyalkylene terephthalate graft polymer in which a vinyl polymer having good compatibility with the ether resin, such as polystyrene, is efficiently grafted by a macromonomer method, extremely good miscibility can be achieved. Therefore, the resin composition obtained by the present invention has the inherent properties of the polyphenylene ether resin and the polyalkylene terephthalate resin that compensate for each other's shortcomings, thereby achieving the heat resistance and dimensional stability that are the properties of the former. It is novel in terms of physical properties in that it combines electrical properties, mechanical strength, water resistance, etc. with weather resistance, oil resistance, chemical resistance, etc., which are the properties of the latter, in a practical manner. Industrially useful as a material.

Claims (1)

[Claims] 1. Polyphenylene ether resin (A) and a graft polymer produced by a macromonomer method (with vinyl polymer segments compatible with the resin (A) as branch components and a polyalkylene terephthalate segment as a backbone component)
A resin composition consisting of B) and containing no polyalkylene terephthalate resin other than the graft polymer (B).