JP3503152B2 - Polyamide resin composition - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyamide, a modified polyolefin and / or a modified styrenic copolymer, and a maleimide copolymer, which have impact resistance, heat resistance,
The present invention relates to a polyamide resin composition having excellent chemical resistance, and provides a material suitable for various fields such as a field of automobiles, a field of OA equipment, a field of home appliances, and a field of miscellaneous goods. 2. Description of the Related Art Polyamide resins are widely used as engineering plastics in automotive parts, electric equipment parts, electronic equipment parts, mechanical parts, etc. because of their excellent physical and chemical properties. However, the polyamide resin has a disadvantage that the impact resistance is not sufficient. [0003] To improve this drawback, a resin composition obtained by blending a modified polyolefin obtained by grafting an α, β-unsaturated carboxylic acid to a polyolefin into a polyamide resin (JP-A-50-964)
No. 42, 52-151348, 55-9
661, 55-9962, 55-16
No. 5922, No. 57-8296, No. 57-2
No. 00948) and some of these compositions have been put to practical use. [0004] However, although these compositions have improved impact resistance, they have heat resistance (such as deformation of molded articles at high temperatures, for example, during the painting process). Such as deformation during the baking process). In view of the above, an object of the present invention is to provide a polyamide composition which has not only excellent impact resistance but also sufficient heat resistance. Means for Solving the Problems The inventors of the present invention have made intensive studies to achieve the above object, and as a result, have accomplished the present invention. That is, the present invention provides (A) a polyamide, (B) a polyolefin and / or a styrene-based copolymer having an unsaturated dicarboxylic acid or an anhydride thereof, and (C) 30 to 90 mol% of an aromatic vinyl monomer unit. Maleimide monomer unit 1
Contains a maleimide copolymer comprising 0 to 70 mol% and 1 to 10 mol% of unsaturated dicarboxylic anhydride units based on 100 mol% of aromatic vinyl monomer units and maleimide monomer units in total. 0.1 ≦ X / Y ≦ 1.0 [wherein X represents the melt viscosity of the mixture of the components (A) and (B), and Y represents the melt viscosity of the component (C)]. The present invention relates to a polyamide resin composition which satisfies the condition and the amount of the component (C) is 10 to 100 parts by weight based on 100 parts by weight of the total of the components (A) and (B). The polyamide (hereinafter also referred to as component (A)) used in the polyamide resin composition of the present invention is a polymer having a —CO—NH— bond in the main chain. , 6-nylon, 6-nylon,
6,6-nylon, 12-nylon, 11-nylon,
6,10-nylon, MXD-nylon and the like. The molecular weight of the polyamide is 8,000 to 4
It is preferably 10,000, and more preferably 10,000.
~ 26,000. Further, the relative viscosity (measured in 98% sulfuric acid) is preferably 2.0 to 5.0, and more preferably about 2.2 to 4.0. The polyamide composition of the present invention contains a polyolefin containing an unsaturated dicarboxylic acid or an anhydride thereof and / or a styrene-based copolymer (hereinafter, also referred to as a component (B)). Examples of the polyolefin include ethylene, propylene, 1-butene, 2-butene, isobutylene, 1-pentene and the like, having 2 or more carbon atoms, preferably 2 to 2 carbon atoms.
And a copolymer of ethylene with an α-olefin having 3 or more carbon atoms, preferably 3 to 6 (propylene, 1-butene, 1-hexene, etc.). Specific examples of the polyolefin include low-density polyethylene, medium-density polyethylene, high-density polyethylene, polypropylene, and ethylene-propylene copolymer. As the styrene copolymer, known S-type copolymers can be used.
It is a so-called styrene block copolymer having a symmetric block type structure of (aromatic hydrocarbon-based polymer) -B (conjugated diene-based polymer) -S. S and B each represent a polymer block, and examples of the central block B include polybutadiene and polyisoprene, with butadiene being preferred. Further, it is recommended that a part of double bonds in polybutadiene be converted to a saturated alkyl group (ethylene chain) by hydrogenation (SEBS). Both end blocks S
It shows a polymer block of an aromatic hydrocarbon, preferably a polymer block made of polystyrene. The molecular weight of the terminal block S is preferably 4,000 to 115,000.
0, more preferably 5,000 to 15,000, and the molecular weight of the central block B is preferably 20,000 to 45.
0000, more preferably 25,000 to 100,0
00. The unsaturated dicarboxylic acid or anhydride thereof to be mixed with the polyolefin and / or styrene copolymer includes maleic anhydride, itaconic anhydride,
Examples include chloromaleic anhydride, citraconic anhydride, butenylsuccinic anhydride, tetrahydrophthalic anhydride, and the like, and particularly preferred is maleic anhydride. One or more of these unsaturated dicarboxylic acids or anhydrides thereof are mixed with a polyolefin and / or styrene copolymer in the presence of a peroxide,
1 to 10 at 100 to 250 ° C with an extruder, mixer, etc.
The mixture is mixed and reacted. The amount of the unsaturated dicarboxylic acid or anhydride is preferably 0.1 to 5% by weight based on the polyolefin and / or styrene copolymer, and the amount of the peroxide is
The content is preferably 0.05 to 1% by weight based on the polyolefin and / or styrene copolymer. The method for producing the maleimide copolymer which is the component (C) of the polyamide resin composition of the present invention is not particularly limited, and examples thereof include an aromatic vinyl monomer, a maleimide monomer and an unsaturated dicarboxylic acid. It can be produced by radical copolymerization of an acid anhydride monomer. Specific examples of the aromatic vinyl monomer include styrene, α-methylstyrene, vinyltoluene and t-butylstyrene, and specific examples of the maleimide monomer include maleimide, N-methylmaleimide, Specific examples of unsaturated dicarboxylic anhydride monomers such as -ethylmaleimide, N-propylmaleimide, N-hexylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, N-tolylmaleimide include maleic anhydride, Examples include methylmaleic acid, 1,2-dimethylmaleic anhydride, ethylmaleic anhydride, and phenylmaleic anhydride. The method for radical copolymerization of these monomers is not particularly limited, and any known radical copolymerization method can be applied. Further, as another method for producing the maleimide copolymer (C), a copolymer produced from an aromatic vinyl monomer, an unsaturated dicarboxylic anhydride monomer and other copolymerizable monomers can be used. A method of reacting a polymer with ammonia or a primary amine to imidize an acid anhydride group present in the copolymer can also be exemplified. The imidization reaction between a polymer having an acid anhydride group in the chain and an amine compound is known, and is described, for example, in JP-B-61-26936.
In accordance with the method disclosed in Japanese Patent Application Laid-Open Publication No. 62-8456 or a polymer disclosed in Japanese Patent Application Laid-Open No. 62-8456, a polymer compound is reacted with an amine compound to produce a maleimide copolymer having an intended imide group. The primary amine used in the imidization reaction includes, for example, methylamine, ethylamine, propylamine, butylamine, hexylamine, cyclohexylamine, decylamine, aniline, toluidine, naphthylamine, chlorophenylamine, bromophenylamine, dibromophenyl Examples include amines. The method of the imidization reaction is arbitrary, and the reaction can be carried out in a solution state, a bulk molten state, or a suspension state using an autoclave. It is also possible to carry out the reaction in a molten state using a melt kneading device such as a screw extruder. The solvent used for the melting reaction is optional.
For example, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, ethers such as tetrahydrofuran and 1,4-dioxane, aromatic hydrocarbons such as toluene and xylene, dimethylformamide, dimethyl sulfoxide, N-methyl-
2-pyrrolidone and the like are exemplified. [0021] The imidization reaction temperature is preferably in the range of 50 to 350 ° C, particularly preferably in the range of 100 to 300 ° C. The imidization reaction does not necessarily require the presence of a catalyst, but if used, a tertiary amine such as trimethylamine, triethylamine, tributylamine, N, N-dimethylaniline, N, N-diethylaniline is preferred. is there. The maleimide copolymer is composed of 30 to 90 mol%, preferably 40 to 65 mol%, of aromatic vinyl monomer units, 10 to 70 mol%, preferably 35 to 60 mol% of maleimide monomer units. , And unsaturated dicarboxylic anhydride monomer unit, 1 to 1 based on a total of 100 mol% of both the aromatic vinyl monomer unit and the maleimide monomer unit.
0 mol%, preferably 1 to 5 mol%. When the amount of the aromatic vinyl monomer unit is less than 30 mol%, it is difficult to produce a polymer having a homogeneous composition industrially with good reproducibility, and the maleimide-based copolymer is mixed with polyamide. The properties such as thermal stability, moldability, and mechanical strength of the obtained composition are inferior. When the content of the aromatic vinyl monomer unit exceeds 90 mol% or the content of the maleimide monomer unit is less than 10 mol%, the heat resistance of the obtained composition is poor, and the maleimide monomer unit is inferior. Exceeds 70 mol%, the moldability of the obtained composition is poor. When the content of the unsaturated dicarboxylic anhydride unit is less than 1 mol% based on 100 mol% of the total of the above two components, the compatibility of the composition obtained by mixing with the polyamide is poor, and a peeling phenomenon is observed.
On the other hand, when the content of the unsaturated dicarboxylic acid anhydride unit exceeds 10 mol%, the melt viscosity is significantly increased due to an excessive reaction, the molding processability is deteriorated, and the surface may be roughened like a shark skin. The thus obtained maleimide-based copolymer preferably has a molecular weight of 100,000 to 300,000, more preferably 120,000 to 250,000. The component (A), the component (B) and the component (C) can be mixed using a usual melt-kneading apparatus. These three components are first mixed with components (A) and component (B), the resulting mixture by mixing the component (C) composition
Get things . The components (A) and (B) are in a weight ratio of 95.
/ 5 to 60/40, preferably 90/10 to 70/30
Mix within the range. The amount of the component (C) is from 10 to 100 based on 100 parts by weight of the total of the components (A) and (B).
Parts by weight, preferably 30 to 100 parts by weight. (C)
The amount of the component is 1 to 100 parts by weight of the components (A) and (B).
When the amount is less than 0 parts by weight, the heat distortion temperature is not improved, and when the amount of the component (C) exceeds 100 parts by weight, the impact resistance becomes insufficient. The polyamide composition of the present invention has the following formula: 0.1 ≦ X / Y ≦ 1.0 wherein X is the melt viscosity of the mixture of the components (A) and (B) (measurement conditions: Resin temperature 285 ° C, shear rate 10 ³ sec
^-1 ), and Y is the melt viscosity of component (C) (measurement conditions: same as above)
Is satisfied. When X / Y is less than 0.1, it is difficult to achieve both high impact resistance and high heat resistance. When X / Y exceeds 1.0, the melt viscosity of the component (A) and the component (B) is greatly increased by melt mixing, and it is difficult to obtain a molded article having a good appearance. Melt viscosity ratio of polyamide composition (X / Y)
Is set to 0.1 to 1.0, for example, when the melt viscosity of the component (C) is determined, the components (A) and (B)
The components are adjusted in consideration of the melt viscosity of the polymer to be used, the amino terminal concentration of the component (A), the acid modification amount of the component (B), the mixing ratio of the components (A) and (B), and the like. For example, as the amino terminal concentration of the component (A) is higher,
The reaction mixture of the components (A) and (B) has a high melt viscosity. Also, the larger the acid modification amount of the polyolefin,
The melt viscosity of the reaction mixture increases. Furthermore, as the compounding ratio of the component (A) and the component (B) approaches 50:50 (volume ratio), the melt viscosity of the reaction mixture increases. The polyamide resin composition of the present invention may optionally contain a fiber reinforced material such as glass fiber or carbon fiber. Furthermore, various additives generally used for the polymer material, for example, a stabilizer, a pigment, a dye, a release agent, a lubricant, a filler, and the like can be appropriately compounded. Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited by these Examples. In the following Examples and Comparative Examples, the number of parts is represented on a weight basis. EXAMPLES Examples 1 to 9 and Comparative Examples 1 to 7 (1) Maleimide copolymer (C) Melt viscosity (resin temperature: 285 ° C., shear rate: 10 ³ sec ^-1 )
Is 6000 poise, maleimide copolymer (Nippon Shokubai Co., Ltd., trade name: Polyimilex PS0262)
It was used. (2) Modified Polyamide A reaction mixture (modified polyamide) obtained by melt-kneading the components (A) and (B) at the ratios shown in Table 1 and adjusted to the melt viscosity shown in Table 1 was used. The component (B) is a polyolefin and / or a styrene-based copolymer shown in Table 1, maleic anhydride as an unsaturated dicarboxylic anhydride is 1.5% by weight based on the polyolefin and / or the styrene-based copolymer, and Perhexin 25 as peroxide
B (manufactured by NOF CORPORATION) was blended at 0.3% by weight with respect to the polyolefin and / or styrene copolymer and melt-mixed. The symbols shown in Table 1 are as follows. HDPE: high-density polyethylene, HIZEX 620
OB, Mitsui Petrochemical Industries, Ltd. PP: polypropylene, H-501, Mitsui Petrochemical Industries, Ltd. EPR: ethylene-propylene copolymer, V-808
P, SEBS manufactured by Exxon Chemical: Hydrogenated SBS type block copolymer, Clayton 1657, nylon shown in Table 1 was used as a component (A) manufactured by Shell Chemical. The symbols in Table 1 are as follows. 6NY-a: 6 nylon having a relative viscosity (measured in 98% sulfuric acid) of 3.50 6NY-b: 6 nylon having a relative viscosity of 2.20 66NY: 6,6 nylon having a relative viscosity of 2.6 The modified polyamide and the maleimide copolymer were blended in the proportions shown in Table 2 and then heated at 265 ° C. with a twin screw extruder.
Into a pellet. Using the obtained pellets, an injection molding machine was used to perform injection molding at a cylinder temperature of 265 ° C. to prepare a test piece. The bending strength, the flexural modulus, the Izod impact, and the deflection temperature under load of the obtained test piece were measured. The results are shown in Tables 2 and 3. The measurement was performed based on the following standards. Flexural strength: ASTM D-638 Flexural modulus: ASTM D-290 Izod impact (1/8 inch): ASTM D-25
6 Deflection temperature under load (18.6 kg / cm ² ): ASTM D-
[Table 2] [Table 3] The polyamide resin composition of the present invention has not only excellent impact resistance but also sufficient heat resistance.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-132140 (JP, A) JP-A-3-207758 (JP, A) JP-A-3-146551 (JP, A) JP-A-3-132 106967 (JP, A) JP-A-6-329853 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08L 1/00-101/16 C08J 3/00-3/28

Claims (1)

(57) [Claims] [Claim 1] (A) Polyamide (provided that terephthalic
Excluding polyamide containing amide units) , (B) polyolefin and / or styrene copolymer having unsaturated dicarboxylic acid or anhydride thereof, and (C) 30 to 90 mol% of aromatic vinyl monomer units, maleimide Maleimide copolymer comprising 10 to 70 mol% of the monomer unit and 1 to 10 mol% of the unsaturated dicarboxylic anhydride unit with respect to 100 mol% of the total of the aromatic vinyl monomer and the maleimide monomer. Containing (A) component and (B) component
The composition obtained by melt-kneading and mixing (C) with the melt-kneading mixture of
Then, the formula: 0.1 ≦ X / Y ≦ 1.0 [where X represents the melt viscosity of the mixture of the components (A) and (B), and Y represents the melt viscosity of the component (C)] satisfied, and (C) Ri amount of component (a) and (B) 10 to 100 parts by weight of der 100 parts by weight of the total of component, (a)
A polyamide resin composition, wherein the weight ratio of the component and the component (B) is from 95/5 to 60/40 .