JPH04175370A - Resin composition - Google Patents

Abstract

PURPOSE:To improve rigidity, impact strength, and heat resistance by compounding a specific multicomponent styrenic copolymer, a polyamide resin, an acrylic rubber of a core-shell type, and a modified silicone oil. CONSTITUTION:A multicomponent styrenic copolymer having an MI of 0. 01-100g/10min is prepd. by copolymerizing 20 wt. % styrenic compd. and 5. 0-60wt.% alpha,beta-unsatd. dicarboximide and/or 0.1-30wt.% unsatd. dicarboxylic acid (anhydride). 10-60wt.% the copolymer, 30-80wt.% polyamide resin, an acrylic rubber of a core-shell type having a mean particle diameter of 0.02-1.0mum and the shell part modified with a carboxylic acid, and 0.01-15wt.% epoxy- or amino- modified silicone oil having a viscosity (25 deg.C) of 10-100000cSt are compounded in a ratio of the acrylic rubber to the sum of the polyamide resin and the rubber of 1-15wt.%.

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. 55-9861, No. 55-9962, No. 55-165922, No. 57-
No. 8296, No. 57-200948).

[Problem to be solved by the invention]

However, although these compositions have improved impact resistance, they have problems in 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 conventional compositions and provide a resin composition with an excellent balance of physical properties, such as high rigidity, 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 extensive 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 modified silicone oil is suitable for the above purpose, and the present invention was completed.

That is, the present invention provides (A) a styrenic multicomponent copolymer comprising at least a styrene compound, an imide compound of α, β to unsaturated dicarboxylic acid, and an unsaturated carboxylic acid and/or an unsaturated dicarboxylic acid anhydride; A composition consisting of B) a polyamide resin, (C) a core-shell type acrylic rubber whose shell portion has been modified with a carboxylic acid, and (D) an epoxy-modified silicone oil and an amino-modified silicone oil, which occupy (A) in the composition.

The ratio of each component (B) and (D) is 10 to 6, respectively.
0 wt%, 30-80 wt96 and 0.01-1.5
% by weight, the proportion of component (C) in the total amount of components (B) and (C) is 1 to 15 t% by weight, and (
A) The copolymerization ratio of unsaturated carboxylic acid and unsaturated dicarboxylic acid anhydride in component is 0.1 as their total amount.
~30. flf amount%, and the copolymerization ratio of the imide compound is 5.0 to 60% by weight, but the copolymerization ratio of the styrene compound is at least 20% by weight, and (
D) A resin composition in which the proportion of epoxy-modified silicone oil in the component is 10 to 90% by weight is provided. 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, talolstyrene and bromstyrene.

Further, examples of imide compounds of α,β-unsaturated dicarboxylic acids include those represented by the general formula or formula (1).

R-C□C-R2NO In (1), R, R and R3 may be the same or different, and are a hydrogen atom or a hydrocarbon group 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, itaconic anhydride, and the like.

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.
0 to 60% by weight, preferably 5.0 to 55% by weight, particularly preferably 5.0 to 50% by weight. If the co-TiL 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 unsaturated carboxylic acid and unsaturated dicarboxylic acid anhydride is 0.1 to 30% by weight as their total amount, preferably 0.1 to 25% by weight, particularly 0.5 to 20% by weight. Oo is suitable. If the copolymerization ratio of unsaturated carboxylic acid and unsaturated dicarboxylic acid anhydride in component (A) or their total amount is less than 0.1% by weight,
Poor compatibility with component (B). On the other hand, if it exceeds 30% by weight, moldability deteriorates. The copolymerization ratio of the styrene compound in component (A) is at least 20% by weight, and if it is less than 20% by weight, 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.

In addition, producing component (A) containing a high proportion of unsaturated carboxylic acid and/or unsaturated dicarboxylic acid anhydride,
When producing the final composition, the component (A) and the styrenic copolymer containing no unsaturated carboxylic acid and/or unsaturated dicarboxylic acid anhydride are mixed in the proportions described above. Good too.

Melt index of component (A) of the present invention (JISK7
21 D at 250° C. and 5) cg. Hereinafter referred to as Ml. ] is usually 0. O1 to 100 g/10 min, preferably 0.05 to 100 g/10 min, particularly preferably 0.1 to 5 (Ig/10 min. Ml or 0.0
If it is less than 1 g/10 minutes, the resulting composition will not have good moldability.

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 -30°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 small part consists of a hard polymer, e.g.
Examples include 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. If the proportion of the core portion is less than 50% by weight, the resulting composition will not have good 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, the impact resistance will be poor.

Furthermore, in the present invention, it is necessary that the shell portion of the acrylic rubber be modified with carboxylic acid.

As the carboxylic acid, a, β-unsaturated carboxylic acid, such as acrylic acid or methacrylic acid, is used, and is obtained by copolymerizing these carboxylic acids with the monomer forming 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 will increase significantly and the moldability will deteriorate.

(D) Epoxy-modified silicone oil and amino-modified silicone oil Furthermore, component (D) used in the present invention is a silicone oil in which an alkyl group is epoxy-modified or amino-modified. A typical example thereof is a modified silicone oil obtained by epoxy-modifying or amino-modifying the alkyl group of polydialkyl (the number of carbon atoms in the alkyl group is 1 to [1 pJ) siloxane.

In addition, component (D) has a viscosity of 1O at 25°C.
~1ooo00cs (centistokes), 5
0 to 50,000 cs is preferred, especially 5O-
20000CS is suitable. If the viscosity at 25° C. is less than locS, there is a risk of volatilization during crosstalk.

On the other hand, if it exceeds 100,000 cs, the compatibility is poor.

(E) Composition ratio The ratio of component (A) in the composition of the present invention is 10 to 6.
0% by weight, preferably 15-55% by weight.

If this ratio is less than 1D weight%, heat resistance and stiffness upon moisture absorption will decrease, which is not preferable. Moreover, if it exceeds 60% by weight, chemical resistance and impact resistance will deteriorate, which is not preferable.

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% by weight
The heat resistance, impact resistance, and rigidity of the composition obtained when the
flexural modulus) becomes unbalanced. Moreover, the rigidity decreases significantly due to moisture absorption.

Furthermore, (
The proportion of component C) is 1 to 15% 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:
The total amount is 0.01-1.5% by weight.

If the proportion of component (D) is less than 0.01% by weight, the impact resistance of the resulting composition will decrease, and if it exceeds 1.5% by weight, the heat resistance will decrease. The proportion of epoxy-modified silicone oil in component (D) is 10 to 90% by weight. If the ratio is outside the above range, the impact resistance will decrease, which is not preferable.

(P) 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 purpose can be achieved by uniformly blending each component. There are no particular restrictions on the blending method (mixing method), and 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 blenders, and melting using mixers such as open rolls, extrusion mixers, kneaders, and Banbury mixers. One method is to mix while To obtain a more uniform composition among these methods, two or more of these mixing methods may be used in combination (for example, tri-blending is performed in advance, and then the mixture is melt-mixed). In particular, even when tri-blend is used in combination, or when a melt-kneading method or two or more methods are used in combination, when producing a molded product by the molding method described later, it is possible to use a pelletizer to produce pellets. It is preferable. In producing the composition, heat, oxygen and light stabilizers, flame retardants, fillers, colorants, lubricants, plasticizers and antistatic agents, which are widely used in the fields of synthetic resins and synthetic rubbers, are also added. Depending on the intended use of the composition, additives may be added 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 at which the polymeric substance used melts. but,
If carried out at high temperatures, the polymeric material may undergo thermal decomposition or 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 D285. In addition, the heat distortion temperature is ASTM
D64g +: Therefore, it was measured at a stress of 18.8 kg/cd.

Furthermore, the flexural modulus is ASTM D7901. :Accordingly,
Measurements were made at a temperature of 23°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> The manufacturing method, type and physical properties of each component are shown below.

[(A) Styrenic multi-component copolymer]

As component (A), a styrenic multi-component copolymer produced as follows was used.

6000 g of water in a 10Ω autoclave, 2400
g of styrene (ST), 680 g of acrylonitrile (AN), 800 g of N-phenylmaleimide (
N-PMI) and 120 g methacrylic acid (MAA)
and 8 g of lauryl peroxide as an initiator, 9.6 g of tertiary butyl peroxide laurate, 8 g of tertiary dodecyl mercaptan as a chain transfer agent, and 60 g of tertiary butyl peroxide as a suspension stabilizer. Calcium triphosphate and 0.9 g of sodium dodecylhenzenesulfonate were added and polymerization was carried out for 2 hours while stirring at a temperature of 80°C. 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. When the obtained powder was determined by infrared absorption spectroscopy (solution method), the weight ratio was ST:AN:
N-PMI:MAA-80:11:20:3. The heat distortion temperature of the obtained powder was 130°C, and M
1 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. When the obtained powder of approximately 3500 i was analyzed in the same manner as copolymer (1), it was found that the weight ratio was ST:AN:N-PMI-60.20.
: It was 20. The heat distortion temperature of the obtained powder (polymer) was 134.2°C, and Ml was 7. l1g/II
) minutes. This is referred to as copolymer (2).

[(B) Polyamide resin]

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

[(C) Core-shell type acrylic rubber] Furthermore, as a core-shell type acrylic rubber whose shell portion has been 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.

This is called rubber (1).

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

[(D) Silicone oil]

Silicone oil (manufactured by Toshi Silicone: S F 8411. (S
J(1)), amino-modified silicone oil with a viscosity of 1200 cs (manufactured by Toshi Silicone: SF 8)
417° (referred to as S 1(2)) was used. For comparison, dimethyl silicone oil with a viscosity of 5000 es (
Made by Toshi Silicone: SH200 (referred to as S1(3)) was used.

Examples 1 to 5, Comparative Examples 1 to 9 Each component whose compounding amount is shown in Table 1 was charged into a Henschel mixer, and triblended for 5 minutes. Pellets were manufactured by kneading each of the obtained mixtures using a co-directional twin-screw extruder (diameter 40+n+s) set at 270°C.

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 iPJ.

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

Table 2 I) 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) High rigidity.

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; (B) a polyamide resin, (C) a core-shell type acrylic rubber whose shell portion is modified with a carboxylic acid, and (D) an epoxy-modified silicone oil and an amino-modified silicone oil, which occupy (A) in the composition; (B
) and (D) The proportions of each component are 10 to 60% by weight, 30 to 80% by weight, and 0.01 to 1.5% by weight, respectively.
, and the proportion of (
The proportion of component C) 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% by weight as their total amount. Yes, and the copolymerization ratio of the imide compound is 5.0~
60% by weight, the copolymerization ratio of the styrene compound is at least 20% by weight, and the ratio of the epoxy-modified silicone oil in component (D) is 10 to 90% by weight.