JPH0411585B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention has excellent environmental agent resistance (oil resistance, chemical resistance, the same applies hereinafter), heat deformation resistance, rigidity, impact resistance, and excellent surface appearance of molded products. The present invention relates to a novel thermoplastic resin composition, and more particularly to a thermoplastic resin composition comprising a polyamide resin, an epoxy group-containing copolymer, and a rubber reinforced resin. (Conventional technology and problems) Polyamide resin is used for electrical and automobile parts because it has excellent heat deformation resistance, rigidity, oil resistance, etc., but it has better impact resistance, water resistance, moldability, etc. Further improvement is desired. On the other hand, ABS resin, which is a typical rubber-reinforced resin, has excellent impact resistance, rigidity, heat deformation resistance, and processability, so it is used in automobile, electrical, and miscellaneous goods parts, but it also has excellent resistance to environmental agents and heat resistance. Further improvements in deformability, rigidity, etc. are desired. Attempts have been made to blend polyamide resin and ABS resin to achieve these modifications.
For example, there is a method of introducing styrene-maleic anhydride (JP-A-56-50931), a method of graft polymerizing acrylamide (JP-A-58-93745), and the like.
However, even these methods are not sufficient to modify the properties of the blend. Polyamide resin and ABS resin are a combination with very poor compatibility and dispersibility, and molded products of the mixture show extreme non-uniformity, resulting in poor surface appearance, layered peeling, and reduced impact resistance, making it difficult to put into practical use. You only get what you can't endure. Furthermore, even when the above-mentioned ABS resins have improved compatibility and dispersibility with polyamide resins, there have been problems such as physical property values often being lower than expected from the additivity of the physical properties of each individual product. However, since polyamide resins and ABS resins each have their own unique characteristics as described above, a thermoplastic resin that has the characteristics of both and can be expected to have a synergistic effect can be obtained by blending them. If possible, it is expected that it will be used for a wider range of purposes. As a result of intensive research, the present inventor has found that it has an excellent balance of physical properties such as resistance to environmental agents, resistance to heat change, rigidity, impact resistance, surface hardness, paintability, and water resistance, can be easily molded, and has uniform surface properties. We have now provided a novel thermoplastic resin composition having the following properties. (Means and effects for solving the problems) That is, the present invention consists of 20 to 80 parts by weight of polyamide resin A, 20 to 80 parts by weight of epoxy group-containing copolymer B, and 0 to 50 parts by weight of rubber reinforced resin C [A+B+C=100
parts by weight]. The polyamide resin A used in the present invention is an aliphatic polyamide, such as polyamide 6, polyamide
6.6, polyamide 6.10, polyamide 11, polyamide 12, polyamide 6.12; aromatic polyamides such as polyhexamethylene diamine, terephthalamide, polyhexamethylene diamine isophthalamide, etc., and mixtures or copolymers of two or more of these are used. You can also do that. In the present invention, epoxy group-containing copolymer B
is particularly important. This epoxy group-containing copolymer contains a copolymer (b-1) of an unsaturated epoxy compound and a vinyl monomer as an essential component, and preferably further contains a graft copolymer (b-2). . The blending ratio is copolymer (b-1)
is 40 to 100 parts by weight, more preferably 50 to 80 parts by weight,
The amount of the graft copolymer (b-2) is 0 to 60 parts by weight, more preferably 20 to 50 parts by weight. Copolymer (b
If -1) is less than 40 parts by weight, it is not preferable because heat deformation resistance and moldability decrease. The intrinsic viscosity of the methyl ethyl ketone bathable component of the epoxy group-containing copolymer B is 0.25 to 1.5 dl/g (N,
N'-dimethylformamide solution, 30°C) range is preferred. If it is less than 0.25dl/g, impact resistance and environmental agent resistance will be lower than if it is 0.25dl/g or more.
In a range exceeding 1.5 dl/g, moldability is lower than in a range of 1.5 dl/g or less. Copolymer (b-1) is an aromatic vinyl compound 20
~80% by weight, 15~50% by weight of vinyl cyanide compound, 0.5~40% by weight of unsaturated epoxy compound, and 0~30% by weight of other copolymerizable vinyl compounds. Aromatic vinyl compounds are 80
If it exceeds 20% by weight, environmental agent resistance, impact resistance, etc. will decrease, and if it is less than 20% by weight, moldability will decrease, which is not preferable. 50% by weight vinyl cyanide compound
If it exceeds 15% by weight, thermal stability during molding will decrease and coloring will be severe due to heating, and if it is less than 15% by weight, environmental agent resistance and impact resistance will decrease, which is not preferable. If the content of the unsaturated epoxy compound exceeds 40% by weight, the molding processability will be significantly reduced, and if it is less than 0.5% by weight, the environmental agent resistance and impact resistance will decrease, and furthermore, layered cracks will occur on the surface of the molded product, which is not preferable. Examples of the aromatic vinyl compound used in the copolymer (b-1) include styrene, methylstyrene, chlorostyrene, and α-methylstyrene. Examples of vinyl cyanide compounds include acrylonitrile and methacrylonitrile. Examples of the unsaturated epoxy compound include unsaturated glycidyl esters and unsaturated glycidyl ethers. Specific examples include glycidyl acrylate, glycidyl methacrylate, allyl itaconate glycidyl ether, and styrene-p-glycidyl ether. Examples of other copolymerizable vinyl compounds include methyl methacrylate, ethyl methacrylate, ethyl acrylate, hydroxyacrylate, butyl acrylate, acrylamide, and phenylmaleimide. The graft copolymer (b-2) is produced by reacting 5 to 95 parts by weight of diene rubber with 95 to 5 parts by weight of a vinyl compound, with 20 to 80% by weight of an aromatic vinyl compound and 15 to 15 to 80% by weight of a vinyl cyanide compound. 50% by weight, 0-40% by weight of an unsaturated epoxy compound, and 0-30% by weight of another copolymerizable vinyl compound. If the diene rubber exceeds 95 parts by weight, impact resistance and environmental agent resistance will decrease, resulting in
If the amount is less than 1 part by weight, impact resistance decreases, which is not preferable. If the aromatic vinyl compound exceeds 80% by weight, impact resistance, resistance to environmental agents, etc. will decrease, and if it is less than 20% by weight, moldability will decrease, which is not preferable. Moreover, if the vinyl cyanide compound exceeds 50% by weight, heat coloring may occur during molding, and if it is less than 20% by weight, environmental agent resistance and impact resistance will deteriorate, which is not preferable. The diene rubber used in the graft copolymer (b-2) is not particularly limited, but the diene component 50
% by weight or more and an average particle diameter of 500 Å to 2 μ is preferable. Furthermore, the aromatic vinyl, vinyl cyanide, unsaturated epoxy compound, and other copolymerizable vinyl compounds used in the copolymer (b-1) can be used. The above copolymer (b-1) and graft copolymer (b-2) are preferably obtained by emulsion polymerization, but are not necessarily limited to emulsion polymerization. Examples include bulk polymerization, solution polymerization, suspension polymerization, and combinations thereof, ie, emulsion-suspension polymerization, emulsion-bulk polymerization, and the like. Conventional methods can be applied to emulsion polymerization. That is, the above compound may be reacted in an aqueous medium in the presence of a radical initiator. At that time, the above-mentioned compounds may be used as a mixture or, if necessary, may be used separately. moreover,
The method of adding the compound may be all added at once or added sequentially, and is not particularly limited. Examples of the radical initiator include water-soluble or oil-soluble peroxides such as potassium persulfate, ammonium persulfate, amene hydroperoxide, and paramenthane hydroperoxide. In addition, polymerization accelerators, polymerization degree regulators, and emulsifiers may be appropriately selected from those used in known emulsion polymerization methods. The polymerization temperature is preferably 30 to 80°C. The method for obtaining the resin from the obtained latex may be any publicly announced method. At that time, the resin may be obtained after mixing the latexes of the copolymer (b-1) and the graft copolymer (b-2), or the resin may be obtained separately. The method of obtaining resin from latex is as follows:
For example, this can be carried out by adding an acid such as hydrochloric acid, sulfuric acid, or acetic acid; or a metal salt such as calcium chloride, magnesium chloride, or aluminum sulfate to the latex. As the rubber reinforced resin C used in the present invention,
ABS resin is preferred. ABS resin is a graft copolymer obtained by reacting two or more compounds selected from aromatic vinyl compounds, vinyl cyanide compounds, and unsaturated carboxylic acid alkyl ester compounds in the presence of diene rubber. . Furthermore, if necessary, it may contain a copolymer obtained by reacting two or more compounds selected from aromatic vinyl compounds, vinyl cyanide compounds, and unsaturated carboxylic acid alkyl ester compounds. The properties of the thermoplastic resin in the present invention vary depending on the mixing ratio of polyamide resin A, epoxy group-containing polymer B, and rubber reinforced resin C, but in the present invention, A20 to 80 parts by weight and B20 to 80 parts by weight are used. A composition ratio of 0 parts and C0 to 50 parts by weight [A+B+C=100 parts by weight] is adopted. If polyamide resin A is less than 20 parts by weight, environmental agent resistance and impact resistance will decrease, and if it exceeds 80 parts by weight, water resistance and moldability will decrease, which is not preferable. If the amount of the epoxy group-containing copolymer B is less than 20 parts by weight, the environmental agent resistance and surface properties of the molded product will deteriorate, and if it exceeds 80 parts by weight, the impact resistance and molding processability will deteriorate, which is not preferable. Also, rubber reinforced resin C
If it exceeds 50 parts by weight, resistance to environmental agents decreases, which is not preferable. Mixing, granulation and shaping can be carried out by known methods. Further, stabilizers, pigments, lubricants, fillers, etc. can be added as necessary. (Examples) The present invention will be described below with reference to Examples, but these are merely illustrative and the present invention is not limited thereto. In addition, unless otherwise specified, "parts" represent parts by weight, and "%" represent weight %. Examples and Comparative Examples (a) Production of copolymer (b-1) The following materials were charged into a reaction vessel equipped with a stirrer. Water 250 (parts) Sodium laurate 3 (〃) Sodium formaldehyde sulfoxylate 0.4 (〃) Ferrous sulfate 0.0025 (〃) Disodium ethylenediaminetetraacetate
0.01 (〃) After deoxidizing the inside of the reaction vessel, while stirring in a nitrogen flow
After heating to 60°C, the compound () shown in Table 1 was charged in the same number of parts as shown in Table 1. After thorough emulsification, a mixture of the compound () shown in Table 1 in the parts shown in Table 1 was continuously added dropwise over 6 hours. Thereafter, stirring was continued at 60° C. for 1 hour to complete the polymerization.

[Table] (b) Production of graft copolymer (b-2) The following substances were charged into a reaction vessel equipped with a stirrer. Water 250 (parts) Sodium formaldehyde sulfoxylate 0.3 (〃) Ferrous sulfate 0.0025 (〃) Disodium ethylenediaminetetraacetate
0.01 (〃) Polybutadiene Predetermined amount (Table 2) After deoxidizing and heating to 60°C while stirring in a nitrogen stream, the compounds shown in Table 2 were continuously added dropwise in the same number of parts shown in Table 2 over 5 hours. , and after the addition was completed, stirring was continued for 1 hour at 60°C to complete the polymerization. The polybutadiene used was latex-like with an average particle diameter of 2500 Å and a gel content of 90%.

[Table] (c) Production of epoxy group-containing copolymer B Copolymer (b-1) produced as in (a) and (b) above
and graft copolymer (b-2) are mixed in a latex state at the predetermined ratios shown in Table 3, a phenolic antioxidant is added to this mixed latex, salted out, washed with water, separated, and dried. A powdered epoxy group-containing copolymer B was obtained.

[Table] (d) Production of thermoplastic resin Polyamide resin A, epoxy group-containing copolymer B
and rubber reinforced resin C (ABS resin) were mixed according to the prescribed comparison shown in Table 4, pelletized using a vented extruder, and test pieces were created by injection molding and used for measuring physical properties. .

[Table] Heat distortion temperature: ASTM D-648, 18.6Kg/ ^cm2 load, (℃) Izot impact value: ASTM D-256, with notch, 23℃, (Kgcm/cm) Tensile strength: ASTM D-636, 23 °C, (Kg/cm ² ) Elongation at break: ASTM D-636, 23 °C, (%) Surface quality of molded product: A flat plate of 150 mm x 100 mm x 3 mm was molded, and the appearance was visually observed to determine whether the surface was uniform. The properties, flow marks, coloring, etc. were evaluated. Good...○, Fair...△, Bad...× Oil resistance: The above flat plate was immersed in toluene and ethylene glycol at room temperature for 10 days, and changes in its appearance were observed. No change was observed...○, change was slightly observed...△, change was significant...×. Chemical resistance: Tested in the same manner as oil resistance. 35% hydrochloric acid was used as the chemical. From Examples 1 to 7 and Comparative Examples 1 to 4 shown in Table 4, the thermoplastic resin composition of the present invention has excellent environmental resistance, heat modification resistance, rigidity, impact resistance, and surface appearance of molded products. I know that there is.

Claims (1)

[Claims] 1. 20 to 80 parts by weight of polyamide resin A, 20 to 80 parts by weight of epoxy group-containing copolymer B, and rubber reinforced resin C0
~50 parts by weight [A+B+C=100 parts by weight],
Core epoxy group-containing copolymer B contains 20 to 80% by weight of an aromatic vinyl compound and 15 to 50% by weight of a vinyl cyanide compound.
wt%, unsaturated epoxy compound 0.5-40 wt%,
40 to 100 parts by weight of a copolymer (b-1) formed by reacting 0 to 30% by weight of another copolymerizable vinyl compound, 5 to 95 parts by weight of diene rubber, and a vinyl compound.
When reacting 95 to 5 parts by weight, 20 to 80 parts by weight of aromatic vinyl compound and 15 to 50 parts by weight of vinyl cyanide compound.
Graft copolymer (b-2) 0 to 60% by weight, obtained by reacting 0 to 40% by weight of an unsaturated epoxy compound and 0 to 30% by weight of another copolymerizable vinyl compound.
A thermoplastic resin composition characterized in that it is a copolymer composition comprising parts by weight [(b-1)+(b-2)=100 parts by weight]. 2 The intrinsic viscosity of the methyl ethyl ketone soluble component of the epoxy group-containing copolymer B is 0.25 to 1.5 dl/g (N,
The thermoplastic resin composition according to claim 1, which is a N'-dimethylformamide solution (30°C).