JPH0737564B2 - Thermoplastic resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to a blended thermoplastic resin composition excellent in various properties such as heat resistance, dimensional stability, impact resistance and melt fluidity, More specifically, it relates to a thermoplastic resin composition comprising a modified polyphenylene ether, a polyamide and a specific modified polyolefin.

<Prior Art> In recent years, active studies have been made to blend two or more kinds of polymers to produce new materials. Polymer blends basically combine polymers with different properties to bring out new characteristics, and if successful, they complement each other in the properties of the raw material components polymers, resulting in useful materials. It is a high technology. However, it is not possible to obtain a material by simply mixing different polymers, and in order to design a truly useful polymer blend material, the structure of the raw material polymer, the degree of polymerization, the mixing method, and the phase in some cases are mixed. Solubilizers and the like must be highly selected and specified.

Polyphenylene ether is a resin excellent in heat resistance, water resistance, and dimensional stability, but has problems such as high melt viscosity and poor moldability, and poor impact resistance and chemical resistance.

On the other hand, polyamides typified by so-called nylon 6 and nylon 66 are excellent in moldability, impact resistance, abrasion resistance, etc., but have slightly low heat resistance, causing problems such as decreased rigidity and dimensions when absorbing water. There is. Therefore, it is considered that new useful materials will be obtained if polyphenylene ether and polyamide are combined to complement each other's advantages and disadvantages.Several studies have been made on blends of polyphenylene ether and polyamide. . To give an example of them, one in which polyphenylene ether and polyamide are simply blended (for example, Japanese Patent Publication No. 45-99).
No. 7, JP-B-59-41663, etc.), polyphenylene ether and polyamide are mixed in the presence of maleic anhydride, linseed oil or an unsaturated compound having a specific functional group represented by liquid polybutadiene or a liquid diene compound. What is done (for example, Japanese Patent Publication No. 60-11966, Japanese Patent Publication No. 61-10494)
(For example, JP-A No. 59-66452), polyphenylene ether, polyamide, and rubber-like substance are modified with a specific compound represented by maleic anhydride and then mixed with polyamide. Examples thereof include those that are mixed in the presence of a specific compound represented by maleic anhydride, linseed oil and liquid polybutadiene (for example, JP-A-56-49763).

<Problems to be Solved by the Invention> However, the mixture of polyphenylene ether and polyamide described in JP-B-45-997 and JP-B-59-41663 is effective in improving the fluidity and chemical resistance of polyphenylene ether. Although there is impact resistance is at most 5 kg ・ c
It is about m / cm / notch and still insufficient. Maleic anhydride, a specific compound such as linseed oil or modified polybutadiene, or a liquid diene compound in a blend of polyphenylene ether and polyamide is added to the resin composition described in JP-B-60-11966 and JP-B-61-109494. The Izod impact strength is at the level of 10 to 13 kg · cm / cm · notch, which is not sufficient yet, and the heat resistance is also insufficient. Further, the mixture of modified polyphenylene ether and polyamide described in JP-A-59-66452 has not yet reached a satisfactory level in impact resistance and heat resistance. JPA
Polyphenylene ether, polyamide, and rubber-like substance described in JP-A-56-49753 are used as maleic anhydride,
The composition obtained by blending in the presence of a specific unsaturated compound represented by linseed oil or liquid polybutadiene has some effects in improving impact resistance and heat resistance, but is still insufficient. There is a drawback that decomposition and foaming are likely to occur when the residence time in the cylinder is long due to poor melt retention stability of the composition and due to melt injection molding.

Therefore, it is the current situation that a material satisfying all of the heat resistance, the dimensional stability, the water resistance, the impact resistance, and the moldability, which mutually complement the properties of both polyphenylene ether and polyamide, has not yet been obtained. The advent of new materials that satisfy all of the characteristics of the above is highly anticipated.

Therefore, an object of the present invention is to obtain a thermoplastic resin composition which is excellent in all of the above properties such as heat resistance, dimensional stability, water resistance, impact resistance, and moldability.

<Means for Solving Problems> As a result of intensive studies to solve the above-mentioned problems, the present inventors have formulated a specific modified polyphenylene ether, a polyamide, and a specific modified polyolefin in a specific ratio. The inventors have found that the objects can be achieved all at once, and have reached the present invention.

That is, the present invention relates to (A) polyphenylene ether obtained by oxidative polymerization of one or more phenols represented by the following general formula (I) and maleic anhydride 0.1 to 10 with respect to 100 parts by weight of the polyphenylene ether. 10 to 80% by weight of modified polyphenylene ether obtained by reacting parts by weight in the presence of a radical generator, (B) 10 to 80% by weight of polyamide, and (C) maleic anhydride-modified ethylene / propylene copolymer 5 to A thermoplastic resin composition comprising 30% by weight is provided.

(Here, R ¹ , R ² , R ³ and R ⁴ are selected from a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a haloalkyl group, an aryl group and a halogen atom, and R ^{1 to} R ⁴ are the same as each other. It may be different.) The polyphenylene ether which is a raw material of the modified polyphenylene ether of the component (A) used in the present invention is obtained by oxidatively polymerizing the phenols represented by the general formula (I). Specific examples of phenols include 2,6
-Dimethylphenol, 2,6-diethylphenol, 2,6
-Dibutylphenol, 2,6-dipropylphenol,
2,6-diphenylphenol, 2-methyl-6-ethylphenol, 2-methyl-5-tolylphenol, 2-
Methyl-6-methoxyphenol, 2-methyl-6-butylphenol, 2,6-dimethoxyphenol, 2,3,6-
Examples include trimethylphenol and 2,3,5,6-tetomethylphenol. Either a homopolymer obtained by polymerizing these phenols alone or a copolymer obtained by polymerizing a mixture of two or more thereof can be used in the present invention. Especially, a homopolymer obtained by polymerizing 2,6-dimethylphenol and a copolymer obtained by copolymerizing a mixture of 2,6-dimethylphenol and 2,3,6-trimethylphenol are preferably used.

The modifying component of the modified polyphenylene ether used in the present invention is maleic anhydride. The amount of maleic anhydride used is in the range of 0.1 to 10 parts by weight with respect to 100 parts by weight of polyphenylene ether. When the amount of maleic anhydride used is less than 0.1 part by weight, modified polyphenylene ether,
A composition obtained by kneading a polyamide and a modified polyolefin lacks impact resistance and heat resistance, and if the amount used exceeds 10 parts by weight, the fluidity of the composition decreases and the moldability is impaired, which is not preferable.

The reaction of polyphenylene ether and maleic anhydride is carried out in the presence of a radical generator, and examples of suitable radical generators include benzoyl peroxide, dicumyl peroxide, di-t-butyl peroxide, t-butyl cumyl peroxide. Oxide, cumene hydroperoxide, 2,5-dimethyl-2,5-di-t-butylperoxyhexane, 2,5
-Dimethyl-2,5-di-t-butylperoxyhexyne-3, azobisisobutyronitrile and the like can be mentioned, and the radical generator is preferably 5 to 10 parts by weight of maleic anhydride. It is used within the range of 30 parts by weight, but the type and amount of radical generator are not limited to these.

Regarding the method of reacting polyphenylene ether and maleic anhydride, a method of reacting in solution using a suitable solvent or a mixture of polyphenylene ether, maleic anhydride and a radical generator at a high temperature of 200 to 350 ° C in the absence of a solvent There is a method of reacting while melting and mixing for 10 seconds to 30 minutes, and any method may be used.

The ratio of the modified polyphenylene ether thus obtained in the final resin composition is 5 to 80% by weight.
If the modified polyphenylene ether is less than 5% by weight, the heat resistance and dimensional stability of the resin composition will be insufficient, and if it exceeds 80% by weight, the moldability of the resin composition will be impaired.

The polyamide as the component (B) used in the present invention is a polyamide containing an amino acid, a lactam, or a diamine and a dicarboxylic acid as main constituent components. Specific examples of the constituents include ε-caprolactam, enantolactam, ω
-Lactams such as laurolactam, ε-aminocaproic acid, 11-aminoundecanoic acid, amino acids such as 12-aminododecanoic acid, tetramethylenediamine, hexamethylenediamine, undecamethylenediamine, dodecamelenediamine, 2,2,4- / 2,4,4-Trimethylhexamethylenediamine, 5-methylnonamethylenediamine, m-xylylenediamine, p-xylylenediamine, 1,3-bisaminomethylcyclohexane, 1,4-bisaminomethylcyclohexane, bis -Diamines such as p-aminocyclohexylmethane, bis-D-aminocyclohexylpropane and isophoronediamine, adipic acid, suberic acid, azelaic acid, sebacic acid, dodecanenic acid, 1,4-
There are dicarboxylic acids such as cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid and dimer acid.
These constituents are subjected to polymerization in the form of a single kind or a mixture of two or more kinds, and any of the polyamide homopolymers and copolymers thus obtained can be used in the present invention. Particularly useful polyamides in the present invention are polycaproamide (nylon 6), polyhexamethylene adipamide (nylon 66), polyhexamethylene sebacamide (nylon 610), polyundecane amide (nylon 11), polydecane. Amides (nylon 12), and copolymers and mixtures of these polyamides. The degree of polymerization of the polyamide used here is not particularly limited, and a 1% concentrated sulfuric acid solution having a relative year at 25 ° C. within a range of 1.5 to 5.0 can be arbitrarily used.

The proportion of polyamide in the resin composition of the present invention is 10 ~
80% by weight. When the polyamide content is less than 10% by weight, the melt flowability and chemical resistance of the resin composition are insufficient, and when the polyamide content exceeds 80% by weight, water resistance and dimensional stability are insufficient, which is not preferable.

The maleic anhydride-modified ethylene / propylene copolymer (C) of the present invention is a copolymer of ethylene and propylene with maleic anhydride introduced.

As a method of introducing maleic anhydride, a method of graft introducing to an ethylene / propylene copolymer using a radical initiator can be used. The amount of maleic anhydride introduced is appropriately within the range of 0.01 to 35 mol% with respect to the total amount of the modified polyolefin.

The proportion of the maleic anhydride-modified ethylene / propylene copolymer in the resin composition of the present invention is in the range of 5 to 30% by weight. If the amount of the modified polyolefin is less than 5% by weight, the impact resistance of the resin composition comprising the modified polyphenylene ether, polyamide and modified polyolefin will be insufficient, which is not preferable. It is not preferable because the properties and rigidity are impaired.

There is no particular limitation on the method for mixing the modified polyphenylene ether, the polyamide and the modified polyolefin, and powders of each resin, fine particles, and a mixture of pellets are generally known such as a single-screw or twin-screw extruder, a Banbury mixer, a kneader, and a mixing roll. Supply to the melt mixer 220 ~ 350 ℃
The method of kneading at the temperature of 1 can be mentioned as an example. The order of mixing the three types of resins is not particularly limited,
Three types of resins may be mixed at once, or two types of resins may be mixed in advance and then mixed with another resin remaining thereafter.

In the resin composition of the present invention, other additives such as pigments, dyes, reinforcing agents, fillers, heat-resistant agents, antioxidants, etc., at the time of mixing the resin and molding, as long as the physical properties are not impaired.
A weathering agent, a lubricant, a release agent, a crystal nucleating agent, a plasticizer, a flame retardant, a fluidity improver, an antistatic agent and the like can be added and introduced.

Molded articles obtained by molding the resin composition of the present invention by methods such as injection molding, blow molding, and extrusion molding have excellent heat resistance, water resistance, dimensional stability, and impact resistance, and these are especially faders for automobiles. , Exterior panels such as door panels, quarter panels, bumpers, spoilers, oil caps, FEEL lids, and side shields, or other general machine parts are extremely useful.

<Examples> The present invention will be described in more detail with reference to Examples.

The properties described in Examples and Comparative Examples were evaluated by the following methods.

(1) Melt index: JIS K7210 (2) Tensile property: ASTM D638 (3) Bending property: ASTM D790 (4) Izod impact strength: ASTM D256 (5) Heat distortion temperature: ASTM D648 (6) Water resistance, dimensional stability Property: The tensile test piece was immersed in water at 23 ° C. for 24 hours, and the water absorption amount and the dimensional change in the vertical direction of the test piece before and after water absorption were measured.

Reference Example 1 (Production of polyphenylene ether) A toluene solution 1 in which 7.6 g of anhydrous cuprous chloride and 10 g of di-t-butylamine were dissolved was charged into a polymerization tank, and then 55% by weight of a toluene solution 4 of 2,6-dimethylphenol was added. The mixture was added and maintained at a temperature of 30 ° C., and the mixed solution was stirred while blowing oxygen to carry out oxidative polymerization. After the polymerization, an acetic acid aqueous solution was added to deactivate the catalyst, the reaction was stopped, the reaction solution was concentrated, and then a large amount of methanol was added to precipitate a polymer. The precipitated polymer was filtered, washed, and dried to obtain polyphenylene ether.

Reference Example 2 (Production of modified polyphenylene ether) 100 parts by weight of the modified polyphenylene ether obtained in Reference Example 1, 1 part by weight of maleic anhydride and 2,5-dimethyl-
A mixture of 0.1 parts by weight of 2,5-di-t-butylperoxyhexane was supplied to the hopper of the extruder, and the cylinder temperature was set to 320.
A maleic anhydride-modified polyphenylene ether (A-1) was obtained by melt-kneading at ° C.

The reaction between the polyphenylene ether and maleic anhydride means that the modified polyphenylene ether was extracted with methanol as a solvent at a bath ratio of 30: 1 for 48 hours, then the IR of the modified polyphenylene ether was observed, and the area of 1,600 to 1,800 cm ^-1 was observed. ν
It was confirmed by analyzing the absorption peak at C = 0.

Example 1 30 parts by weight of modified polyphenylene ether (A-1) prepared by the method described in Reference Example 2, 60 parts by weight of nylon 66 resin (CM3001N manufactured by Toray Industries, Inc.) and 1 part of maleic anhydride were used.
After premixing 10 parts by weight of ethylene-propylene copolymer (C-1) containing 0.4% / 10% melt index, it was supplied to the hopper of a twin-screw extruder with a diameter of 30 mm and the cylinder temperature was 280 ° C. Melted and kneaded into pet. After vacuum-drying the pellets, the pellets were injected under the conditions of a Schirender temperature of 280 ° C. and a mold temperature of 80 ° C. to obtain test pieces for evaluating various physical properties. The characteristics of the test pieces are shown in Table 1. The resin composition obtained here has heat resistance represented by heat distortion temperature, dimensional stability represented by dimensional change during water absorption, water resistance represented by water absorption, and impact resistance represented by Izod impact strength. Were found to be very well balanced and highly practical materials.

Comparative Example 1 Kneading and injection molding were carried out in the same manner as in Example 1 except that polyphenylene ether polymerized by the method shown in Reference Example 1 was used in place of the modified polyphenylene ether (A-1), and various test pieces were obtained. Obtained. These properties are as shown in Table 1, and the impact strength and heat resistance were insufficient.

Comparative Example 2 40 parts by weight of the modified polyphenylene ether (A-1) and 60 parts by weight of the nylon 66 resin used in Example 1 were premixed without adding the modified polyolefin, and at all as described in Example 1 below. Kneading and injection molding were performed in the same procedure to obtain various test pieces. The properties of the test piece obtained here are as shown in Table 1, and the impact strength was insufficient.

Comparative Example 3 30 parts by weight of unmodified polyphenylene ether, nylon 66
60 parts by weight of the resin, 10 parts by weight of the modified polyolefin (C-1) used in Example 1 and 2 parts by weight of maleic anhydride were mixed, and kneading was carried out by the same operation as described in Example 1 below.
Injection molding was performed. The physical properties of the test piece obtained here are as shown in Table 1, and the impact strength of this test piece was also unsatisfactory. In addition, this composition has foaming in the cylinder during molding and has poor melt stability.

<Effect of the Invention> The feature of the present invention resides in that a modified polyphenylene ether modified with a specific compound, a polyamide resin and a specific modified polyolefin are combined in a specific composition ratio. This makes it possible to combine the advantages of both polyphenylene ether and polyamide in a well-balanced manner, and a new thermoplastic resin composition with excellent properties such as heat resistance, dimensional stability, water resistance, impact resistance, and moldability. You can get things.

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Claims (1)

[Claims] 1. A polyphenylene ether obtained by oxidative polymerization of (A) one or more phenols represented by the following general formula (I) and the polyphenylene ether.
Modified polyphenylene ether obtained by reacting 0.1 to 10 parts by weight of maleic anhydride with 0 to 10 parts by weight in the presence of a radical generator, (B) 10 to 80% by weight of polyamide, and (C) A thermoplastic resin composition comprising 5 to 30% by weight of a maleic anhydride-modified ethylene / propylene copolymer. (Here, R ¹ , R ² , R ³ and R ⁴ are selected from a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a haloalkyl group, an aryl group and a halogen atom, and R ^{1 to} R ⁴ are the same as each other. It may be different.)