JPH04173863A - Resin composition - Google Patents

Abstract

PURPOSE:To provide the title composition excellent in heat resistance, impact resistance etc., suitable for automotive parts etc., comprising a specific styrene- based multicomponent copolymer, polyamide resin, core shell-type acrylic rubber and silicone oil at specified proportion. CONSTITUTION:The objective composition comprising (A) 10-60wt.% of a styrene-based multicomponent copolymer produced from (1) >=20wt.% of at least styrene-based compound, (2) 5-60wt.% of an imide compound of alpha,beta-unsaturated dicarboxylic acid and (3) 0.1-30wt.% of an unsaturated carboxylic acid and/or unsaturated dicarboxylic acid anhydride, (B) 30-80wt.% of a polyamide resin, (C) 0.01-1.5wt.% of a silicone oil and (D) 1-15wt.%, based on the total weight of the components B and D, of a core shell-type acrylic rubber wherein the shell part is modified with carboxylic acid.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a highly rigid resin composition with excellent impact resistance.

More specifically, the present invention relates to a resin composition with an excellent balance of physical properties, such as high rigidity, excellent impact resistance, and heat resistance, which is suitable as a material for automobile parts, electric/electronic equipment parts, etc.

[Conventional technology]

Polyamide resin is used as an engineering plastic due to its excellent physical and chemical properties.
It is widely used in automobile parts, electrical equipment parts, electronic equipment parts, mechanical parts, etc.

However, polyamide resins have the drawback of not having sufficient impact resistance. In order to improve this point, a composition containing a modified polyolefin obtained by grafting α,β-unsaturated carboxylic acids to a polyamide resin has been proposed (Japanese Patent Laid-Open No. 50-96442
No. 52-151348, No. 55-9611i1, No. 55-9962, No. 55-165922, No. 5
No. 7-8296, No. 57-200948).

[Invention or problem to be solved]

However, although these compositions have improved impact resistance, they have the problem that not only heat resistance but also rigidity decreases. Furthermore, it has the disadvantage that the rigidity decreases significantly when moisture is absorbed.

The present invention aims to overcome the drawbacks of such conventional compositions and provide a resin composition with an excellent balance of physical properties, such as high rigidity, and excellent impact resistance and heat resistance. It was done for a purpose.

[Means and effects for solving the problem] The inventors,
As a result of intensive research, it was discovered that a composition consisting of a styrene multi-component copolymer, a polyamide resin, a core-shell type acrylic rubber, and a silicone oil is suitable for the above purpose, and the present invention was completed. That is, the present invention provides (A) at least a styrene compound, α, β
- A styrenic multi-component copolymer consisting of an imide compound of an unsaturated dicarboxylic acid and an unsaturated carboxylic acid and/or an unsaturated dicarboxylic acid anhydride, (B) a polyamide resin, (C) a core shell whose shell portion is modified with a carboxylic acid. A composition consisting of acrylic rubber of the type (A) and (D) a silicone oil.

The ratio of each component (B) and (D) is 10 to 6, respectively.
0% by weight, 30-80% by weight, and 0.01-1.5% by weight, and the proportion of component (C) in the total amount of components (B) and (C) is 1-15% by weight. Yes, (A
) The copolymerization ratio of unsaturated carboxylic acid and unsaturated dicarboxylic acid anhydride in the component is 0.1 to 0.1 as the total amount thereof.
The present invention provides a resin composition in which the copolymerization ratio of the imide compound is 5.0 to 60% by weight, and the copolymerization ratio of the styrene compound is at least 20% by weight. The present invention will be specifically explained below.

(A) Styrenic multi-component copolymer The styrene compound which is the copolymerization component of component (A) used in the present invention is styrene or a derivative thereof, and the derivatives include α-methylstyrene, 0-
Mention may be made of methylstyrene, m-methylstyrene, p-methylstyrene, chlorstyrene and bromstyrene.

Examples of imide compounds of α,β-unsaturated dicarboxylic acids include those whose numerical formula is represented by formula (1).

In NO (I), R, R and R3 may be the same or different and are hydrogen atoms or hydrocarbon groups having at most 12 carbon atoms.

Representative examples of the imide compounds include maleimide, N-
Phenylmaleimide, N-methylphenylmaleimide,
Examples include N-ethylphenylmaleimide, N-cyclohexylmaleimide, N-laurylmaleimide, N-p-chlorophenylmaleimide, and the like.

Furthermore, as an unsaturated carboxylic acid, the number of carbon atoms is at most 3.
Mention may be made of α,β-unsaturated monocarboxylic acids having 0 carbon atoms, preferably 25 or less carbon atoms, and α,β-unsaturated dicarboxylic acids having at most 30 carbon atoms, preferably 25 carbon atoms or less. Representative examples of preferred unsaturated carboxylic acids include acrylic acid, methacrylic acid, maleic acid, fumaric acid, and itaconic acid.

Preferred examples of the unsaturated dicarboxylic anhydride include maleic anhydride, fumaric anhydride, and itaconic anhydride.

Component (A) can be produced by any of the commonly used methods such as aqueous suspension polymerization, emulsion polymerization, solution polymerization, and bulk polymerization, and these polymerization methods are generally well known.

The copolymerization ratio of the imide compound in component (A) is 5.
The amount is 0 to 60% by weight, preferably 5.0 to 55% by weight, and particularly preferably 5.0 to 50% by weight. If the copolymerization ratio of the imide compound in component (A) is less than 5.0% by weight, heat resistance will be insufficient. On the other hand, if it exceeds 60% by weight, moldability and mechanical properties are poor.

Further, the copolymerization ratio of α,β-unsaturated carboxylic acid and α,β-unsaturated dicarboxylic acid anhydride is 0.1 to 30% by weight as their total amount, preferably 0.1 to 25% by weight. , especially 0.5 to 20% by weight. (
^) α, β-unsaturated carboxylic acid and α, β- in the ingredients
If the copolymerization ratio of unsaturated dicarboxylic acid anhydrides is less than 0.1% by weight in total, the compatibility with component (B) is poor. On the other hand, if it exceeds 30% by weight, moldability decreases. In addition, the copolymerization ratio of the styrene compound in component (A) is at least 20% by weight, and 20% by weight? . Otherwise, the moldability of the resulting composition is poor.

Component (A) of the present invention further includes unsaturated nitrile compounds (for example, acrylonitrile, methacrylate).
A copolymer of at most 30% by weight of an ester of acrylic acid or methacrylic acid (for example, methyl acrylate, methyl methacrylate) as a copolymerization component may also be used.

Component (A) containing a high proportion of unsaturated carboxylic acid and/or unsaturated dicarboxylic acid anhydride is produced;
) component and a styrenic copolymer containing no unsaturated carboxylic acid and/or unsaturated dicarboxylic acid anhydride may be mixed in the above ratio when producing the final composition. .

Melt index of component (A) of the present invention [JIsK7
210, at 250°C and 5 kg. Below MI
That's what it means. ] is usually 0.01 to loOg/10 minutes,
0.05 to 100 g/10 min is preferred, especially 0.05 to 100 g/10 min.
1 to 50 g/10 minutes is suitable. Ml or 0.01g/
If the time is less than 10 minutes, the moldability of the resulting composition will be poor.

On the other hand, if it exceeds 100 g/10 minutes, mechanical strength is poor.

(B) Polyamide resin The component (B) in the present invention is described in Japanese Patent Application Laid-Open No.
The polyamide resins described in Publication No. 51547, page 3, lower left column, line 17 to page 4, upper left column, line 7, can be used.

(C) Acrylic Rubber The acrylic rubber in the present invention is a core-shell type. The core part is mainly composed of an acrylic ester polymer, for example, it is made by polymerizing an acrylic ester monomer and a small amount of a crosslinking monomer, and has a glass transition temperature of 130°C.
Examples include the following rubbery polymers. As the acrylic acid ester monomer, one having an alkyl group preferably having 1 to 12 carbon atoms, most preferably 2 to 8 carbon atoms is used. Further, examples of the crosslinkable monomer include compounds having two or more double bonds such as butylene glycol diacrylate and hexane diacrylate. Furthermore, monomers copolymerizable with acrylic esters, such as styrene, α-methylstyrene, vinyl halides,
Acrylic acid esters copolymerized with vinylidene halide, acrylonitrile, methyl methacrylate, etc. can also be used.

On the other hand, the shell portion is made of a hard polymer, such as polymethyl methacrylate, polystyrene, and a copolymer of styrene and acrylonitrile. The proportion of the core portion in the acrylic rubber is 50 to 90% by weight
It is. If the proportion of the core portion is less than 50% by weight, the resulting composition will have poor impact resistance, and if it exceeds 90% by weight, the heat resistance will decrease, which is not preferable.

Moreover, the average particle size of the acrylic rubber is 0.02 to 1.0 microns. If the average particle size is outside the above range, impact resistance will be poor.

Furthermore, the present invention requires that the shell portion of the acrylic rubber be modified with carboxylic acid.

As the carboxylic acid, α,β-unsaturated carboxylic acids such as acrylic acid and methacrylic acid are used, and these carboxylic acids are obtained by copolymerizing the monomer that will become the shell portion. The proportion of carboxylic acid in the shell is 0.
It is 1 to 30% by weight. If the proportion of carboxylic acid is less than 0.1% by weight, the resulting composition will have poor impact resistance. On the other hand, if it exceeds 30% by weight, the viscosity of the resulting composition increases significantly and moldability deteriorates.

(D) Silicone oil Furthermore, the component (D) used in the present invention has a viscosity of 10 to 100,000 ep (centipoise) at 25°C, preferably 50 to 50,000 cp,
Particularly suitable is one having a content of 50 to 20,000 cp. 2
If the viscosity at 5° C. is less than 10 cp, there is a risk of volatilization during kneading. On the other hand, if it exceeds 100,000 cp, the compatibility is poor. As typical examples of component (D), polydimethylsiloxane, polymethylphenylsiloxane, and polymethylhydrogensiloxane are mainly used. Furthermore, polydialkyl (the number of carbon atoms in the alkyl group is 1
~18) Modified silicone oil obtained by modifying the alkyl group of siloxane with epoxy, alkyl, amino, carboxyl, or alcohol can also be used.

(E) Composition ratio The ratio of the component (^) in the composition of the present invention is 10 to 6
0% by weight, preferably 15-55% by weight fA. If this proportion is less than 10% by weight, the resulting composition will have poor heat resistance and stiffness upon moisture absorption, which is undesirable. Moreover, if it exceeds 60 weight ff196, chemical resistance and impact resistance will deteriorate, which is not preferable.

Further, the composition ratio of component (B) in the composition of the present invention is 30 to 80% by weight, preferably 30 to 75% by weight, and particularly preferably 35 to 70% by weight. If the proportion of component (B) in the composition is less than 30% by weight, the resulting composition will have poor chemical resistance. - side, 80% heavy plate
If it exceeds this, the balance of heat resistance, impact resistance, and rigidity (flexural modulus) of the resulting composition will be poor. Moreover, the rigidity decreases significantly due to moisture absorption.

Furthermore, (
C) The proportion of component is 1-1596 by weight. If the proportion of component (C) is less than 1% by weight, the impact resistance of the resulting composition will decrease. On the other hand, if it exceeds 15% by weight, heat resistance and rigidity decrease, which is not preferable.

Furthermore, the proportion of component (D) in the composition of the present invention is 0.
．． 01-1.5% by weight. (D) The proportion of the component is 0.
If the amount is less than 1.5% by weight, the impact resistance of the resulting composition will decrease, and if it exceeds 1.5% by weight, the heat resistance will decrease.

(F) Manufacture and molding method of resin composition The resin composition of the present invention is produced by the above-mentioned (A), (B), (C) and (
D) The objective can be achieved by uniformly blending each component.

There are no particular restrictions on the blending method (mixing method).
Any method commonly used in the field of synthetic resins may be applied. Mixing methods include tri-blending using commonly used mixers such as Henschel mixers, tumblers, and ribbon mixers, and melting using mixers such as open rolls, extrusion mixers, kneaders, and Banbury mixers. There is a method of mixing while Among these methods, two or more of these mixing methods may be used in combination to obtain a uniform composition (for example, after tri-blending in advance, the mixture is melt-mixed). In particular, even when tri-blend is used in combination, or when one or more melt-mixing methods are used in combination, when producing a molded product by the molding method described below, it is important to use a pelletizer to produce pellets. is preferred. In addition, in producing the composition, stabilizers against heat, oxygen and light, which are widely used in the fields of synthetic resins and synthetic rubbers, are used.
Additives such as flame retardants, fillers, colorants, lubricants, plasticizers, and antistatic agents may be added depending on the intended use of the composition to the extent that they do not essentially impair the properties of the composition of the present invention. .

Of the above mixing methods, both melt mixing and molding using the molding method described below must be carried out at a temperature that melts the polymeric substance used. but,
If carried out at high temperatures, the polymeric material will undergo thermal decomposition and deterioration. For these reasons, the temperature is generally 180 to 350℃.
(preferably 200 to 320°C).

The composition of the present invention may be molded into a desired shape by applying molding methods commonly practiced in the field of synthetic resins, such as injection molding, extrusion molding, compression molding, and blow molding. Alternatively, after forming into a sheet using an extrusion molding machine, this sheet may be formed into a desired shape by a secondary processing method such as a vacuum forming method or a pressure forming method.

[Examples and comparative examples]

Hereinafter, the present invention will be explained in more detail with reference to Examples.

In the Examples and Comparative Examples, the Izot impact strength was measured with a notch at a temperature of 23° C. according to ASTM D265. In addition, the heat distortion temperature is ASTM
Measured at a stress of 18.6 kg/c according to D848.

Furthermore, the flexural modulus is 23 according to ASTM D790.
Measured at a temperature of °C. In addition, in the moisture absorption test, the test piece was immersed in boiling water at 100° C. for 30 minutes, and then the flexural modulus was measured.

In addition, (A) used in Examples and Comparative Examples,
(B), (C) and (D) manufacturing method of each component,
The types and physical properties are shown below.

[(^) Styrenic multi-component copolymer]

As component (A), a product manufactured as follows was used.

10 g of autoclave, eooo g of water, 2400
g of styrene (ST), 680 g of acrylonitrile (AN), 800 g of N-phenylmaleimide (N-
PMI) and 120 g of methacrylic acid (MAA), 8 g of lauryl peroxide and 9.6 g of tertiary butyl peroxylaurate as an initiator, 8 g of tertiary dodecyl mercaptan as a chain transfer agent, and 120 g of methacrylic acid (MAA). As a turbidity stabilizer, 60 g of tricalcium phosphate and 0.9 g of sodium dodecylbenzenesulfonate were added, and polymerization was carried out at a temperature of 80° C. for 2 hours with stirring. Next, the temperature of the polymerization system was raised to 120° C., and after polymerization was carried out at this temperature for 3 hours, the polymerization system was allowed to cool to room temperature. As a result, about 3500 g of pale yellow powder was obtained. The obtained powder was subjected to infrared absorption spectroscopy (
The weight ratio of ST:AN:N-P was determined by
MI:MAA-[io:17.20:3. The heat distortion temperature of the obtained powder was 130° C., and the Ml was 16.2 g/10 minutes.

This is referred to as copolymer (1).

For comparison, polymerization was carried out in the same manner as for copolymer (1) except that the entire amount of MAA used in producing copolymer (1) was changed to AN. About 3500 g of the obtained powder was analyzed in the same manner as copolymer (1), and the weight ratio was ST: AN: N-PMI-60.
:20:20. The heat distortion temperature of the obtained powder (polymer) was 134.2°C, and the Ml was 17.8/10
It was a minute. This is referred to as copolymer (2).

[(B) Polyamide resin]

In addition, as component (B), relative viscosity η (in concentrated sulfuric acid, 3
Nylon 66 (hereinafter referred to as P A
It is called (a). ) and Suiron 6 (hereinafter referred to as P A (b)) having η of 2.7 were used.

[(C) Core-shell type acrylic rubber] Furthermore, as a core-shell type acrylic rubber whose shell portion is modified with carboxylic acid, Staphyloid I M
-301 (manufactured by Takeda Pharmaceutical Co., Ltd.) was used. The average particle size of this rubber is 0.3 microns. Add this to rubber (1
).

Further, as comparative examples, rubber (1) whose shell was not modified with carboxylic acid (rubber (2)) and EPR rubber modified with maleic anhydride (rubber (3)) were used.

[(D) Silicone oil]

As component (D), the viscosity at 25°C (the same applies hereinafter) is 5.
Polydimethyl silicone oil (S
J(1)) and an amino-modified silicone oil (Sl(2)) having a viscosity of 600 cp were used.

Examples 1 to 4, Comparative Examples 1 to 4 Each component whose compounding amount is shown in Table 1 was charged into a Henschel mixer, and dry blended for 5 minutes. Each of the obtained mixtures was kneaded using a co-directional twin-screw extruder (diameter 40 mm) set at 270° C. to produce pellets. Each of the obtained pellets was vacuum dried at a temperature of 80°C for 48 hours, and then injection molded using an injection molding machine set at 270°C to prepare test pieces for measurement.

Next, each test piece was subjected to a heat resistance test, a moisture absorption test, and measurements of Izot impact strength and flexural modulus. The results are shown in Table 2.

Table 2 1) Notched 〔Effect of the invention〕 The resin composition of the present invention exhibits the following effects.

(1) Excellent heat resistance.

(2) Decrease in rigidity due to moisture absorption is small.

(3) Excellent impact resistance.

(4) Rigidity is low.

The resin composition of the present invention can be used in a wide variety of ways to achieve the effects described above. Typical uses are shown below.

(1) Automotive exterior panels such as fenders and rear panels (
2) Automotive parts such as oil covers and radiator grills (3) Mechanical and electrical parts such as connectors and transformer cases

Claims (1)

[Scope of Claims] (A) A styrenic multi-component copolymer comprising at least a styrene compound, an imide compound of an α,β-unsaturated dicarboxylic acid, and an unsaturated carboxylic acid and/or an unsaturated dicarboxylic acid anhydride; It is a composition consisting of (B) polyamide resin, (C) core-shell type acrylic rubber whose shell portion is modified with carboxylic acid, and (D) silicone oil, which occupy (A) and (B) in the composition.
) and (D) components are 10 to 60% by weight, 30 to 80% by weight, and 0.01 to 1.5% by weight, respectively, based on the total amount of components (B) and (C). The proportion of component (C) in the total amount is 1 to 15% by weight, and the copolymerization proportion of unsaturated carboxylic acid and unsaturated dicarboxylic acid anhydride in component (A) is 0.1 to 30% in total. % by weight, and the copolymerization ratio of the imide compound is 5.0
~60% by weight, but the copolymerization proportion of the styrenic compound is at least 20% by weight.