JP2000017170A - Thermoplastic resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin composition having improved fluidity and excellent heat resistance and rigidity without reducing impact resistance in a polyamide/ ABS alloy. SOLUTION: This compound comprises 10-80 pts. wt. of a polyamide resin (A), 10-80 pts.wt. of a graft polymer (B) obtained by subjecting 90-20 wt.% of a monomer mixture composed of 50-90 wt.% of an aromatic vinyl and 10-50 wt.% of vinyl cyanide to graft polymerization in the presence of 10-80 wt.% of a diene-based rubber, 1-40 pts.wt. of an unsaturated carboxylic acid modified copolymer (C) which is obtained by polymerizing 0.5-20 wt.% of an unsaturated carboxylic acid monomer with 50-89.5 wt.% of an aromatic vinyl and 10-49.5 wt.% of vinyl cyanide and has 0.2-0.5 dl/g reduced viscosity and 0-50 pts.wt. of a copolymer (D) obtained by polymerizing 50-90 wt.% of an aromatic vinyl with 10-50 wt.% of vinyl cyanide [the total of the components A+B+C+D is 100 pts.wt.].

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a thermoplastic resin composition. More specifically, the present invention relates to a thermoplastic resin composition having an excellent balance of impact resistance and fluidity, and having excellent heat resistance and rigidity.

[0002]

2. Description of the Related Art Polyamide resin has chemical resistance, heat resistance,
It is a resin excellent in abrasion resistance and the like, and is widely used as an automobile part and an electric / electronic part, but has a drawback of poor impact resistance. ABS resin (acrylonitrile-butadiene-styrene copolymer resin) is a resin having excellent impact resistance and moldability, and is widely used as office equipment parts, electric parts, automobile parts, etc. However, it has a drawback of poor abrasion resistance. Therefore, in order to compensate for these disadvantages, polyamide resin and ABS
A blend of resins, that is, a polyamide / ABS alloy has been proposed (Japanese Patent Publication No. 38-23476). However, since the polyamide resin and the ABS resin have poor compatibility, as a method for improving the compatibility, a method of blending a modified copolymer obtained by copolymerizing an unsaturated carboxylic acid with styrene and acrylonitrile has been proposed. (JP-A-63-179957 and JP-A-64-158). These methods have shown improvements in compatibility and some improvements in impact resistance and the like have been recognized. On the other hand, resin moldings made of these materials, for example, home appliances such as large TV housings, refrigerator outer panel panels, vehicle parts such as door panels, wheel caps, bumpers, fenders, etc., require a molding cycle from the viewpoint of productivity. In order to improve the material, a material having excellent fluidity is desired. In general, when the amount of rubber provided from ABS is reduced to improve the flowability of PA / ABS alloy, impact resistance is reduced. This is especially AB
This is a fatal drawback for S-rich PA / ABS alloys. Therefore, under these circumstances, polyamide / AB
In S alloy, a resin composition having improved flowability without lowering impact resistance is desired.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a polyamide / ABS alloy which has improved flowability and excellent heat resistance and rigidity without deteriorating impact resistance. It is assumed that.

[0004]

SUMMARY OF THE INVENTION The present invention provides a polyamide resin and an ABS resin which are blended with an unsaturated carboxylic acid-modified copolymer having a specific reduced viscosity, without deteriorating impact resistance. , Improved fluidity and heat resistance,
It is intended to provide a resin composition having excellent rigidity. In the present invention, in particular, by using an agglomerated and enlarged rubber obtained by agglomerating a small particle rubber having a specific particle diameter as a diene rubber component of the graft polymer constituting the ABS resin, the impact resistance and the flow are further improved. A resin composition having an excellent balance of properties can be obtained.

That is, the present invention relates to a polyamide resin (A)
A monomer mixture 90 comprising 10 to 80 parts by weight, 50 to 90% by weight of an aromatic vinyl monomer and 10 to 50% by weight of a vinyl cyanide monomer in the presence of 10 to 80% by weight of a diene rubber. 10 to 80 parts by weight of a graft polymer (B) obtained by graft polymerization of 20 to 20% by weight, 0.5 to 20% by weight of an unsaturated carboxylic acid monomer, 50 to 50% by weight of an aromatic vinyl monomer
89.5% by weight and vinyl cyanide monomer 10-4
Reduced viscosity of 0.2 to 0.5 d obtained by polymerizing 9.5% by weight
1 / g of unsaturated carboxylic acid-modified copolymer (C) 1 to 40
0 to 50 parts by weight of a copolymer (D) obtained by polymerizing 50 to 90% by weight of an aromatic vinyl monomer and 10 to 50% by weight of a vinyl cyanide monomer [however, (A)
(The total of (B), (C) and (D) is 100 parts by weight)].

The polyamide resin (A) used in the present invention includes nylon 6, nylon 46, nylon 6
6, Nylon 610, Nylon 612, Nylon 11
6, Nylon 11, Nylon 12, Nylon 6I, Nylon 6/66, Nylon 6T / 6I, Nylon 6/6
T, nylon 66 / 6T, polytrimethylhexamethylene terephthalamide, polybis (4-aminocyclohexyl) methandodecamide, polybis (3-methyl-4-
(Aminocyclohexyl) methandodecamide, polymethaxylylene adipamide, nylon 11T, polyundecamethylene hexahydroterephthalamide and the like.
Here, "I" indicates an isophthalic acid component, and "T" indicates a terephthalic acid component.

Of these, nylon 6, nylon 46, nylon 66, nylon 6T / 6I, nylon 6
/ 6T and nylon 66 / 6T are preferred.

[0008] The graft polymer (B) used in the present invention is defined as 50 to 90% by weight of an aromatic vinyl monomer and 10 to 80% by weight of a vinyl cyanide monomer in the presence of 10 to 80% by weight of a diene rubber. Monomer mixture 9 consisting of 50% by weight
It is a graft polymer obtained by graft polymerization of 0 to 20% by weight.

The diene rubber constituting the graft polymer (B) is a polymer obtained by polymerizing a monomer containing 50% by weight or more of a diene monomer represented by, for example, 1,3-butadiene. Other monomers copolymerizable with the diene monomer include aromatic vinyl monomers such as styrene and α-methylstyrene, and vinyl cyanide monomers such as acrylonitrile and methacrylonitrile. And unsaturated carboxylic acid alkyl ester-based monomers such as methyl acrylate, ethyl acrylate and methyl methacrylate. Specifically, it is a polybutadiene, a butadiene-styrene copolymer, a butadiene-acrylonitrile copolymer, or a butadiene-methyl methacrylate copolymer. The gel content (solvent: toluene) of the diene rubber is not particularly limited, but preferably 60 to 95% by weight.

Examples of the aromatic vinyl monomer constituting the graft polymer (B) include styrene, α-methylstyrene, paramethylstyrene, chlorostyrene, bromostyrene, and the like. One or more kinds may be used. be able to. Particularly, styrene and α-methylstyrene are preferred.
Acrylonitrile, as a vinyl cyanide monomer,
Methacrylonitrile and the like can be mentioned, and one kind or two or more kinds can be used. Acrylonitrile is particularly preferred. Further, in the present invention, a part of the aromatic vinyl-based monomer may be another copolymerizable vinyl-based monomer such as maleimide, methylmaleimide, ethylmaleimide, N-
Maleimide monomers such as phenylmaleimide and O-chloro-N-phenylmaleimide; unsaturated carboxylic acid ester monomers such as methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate and 2-ethylhexyl acrylate; It may be replaced.

In the present invention, in view of the balance between impact resistance and fluidity, heat resistance and rigidity, the diene rubber constituting the graft polymer (B) is particularly suitable for small particles having a specific particle diameter. It is preferable to use a coagulated and enlarged rubber obtained by coagulating rubber. Specifically, it is possible to use a diene rubber latex obtained by coagulating and enlarging a small particle diene rubber latex having a weight average particle diameter of 0.05 to 0.20 μ to a weight average particle diameter of 0.20 to 0.8 μ. preferable. As a method for coagulating and enlarging the small particle diene rubber latex, a conventionally known method, for example, a method of adding an acidic substance (Japanese Patent Publication No. 42-3112, Japanese Patent Publication No. 55-55)
19246, Japanese Patent Publication 2-9601, JP-A-63-117
005, JP-A-63-132903, JP-A-7-157
501, JP-A-8-259777), a method of adding an acid group-containing latex (JP-A-56-166201, JP-A-59-93701, JP-A-1-126301, JP-A-8-126301)
-59704) can be adopted, and there is no particular limitation.

The method for producing the above graft polymer is not particularly limited, and it can be polymerized by an emulsion polymerization method, a suspension polymerization method, a bulk polymerization method, a solution polymerization method or a combination thereof. When a rubber latex is used, a usual emulsion polymerization method can be employed, and known emulsifiers, initiators, and various auxiliaries can be used without any limitation.

The unsaturated carboxylic acid-modified copolymer (C) used in the present invention is defined as 0.5 to 20% by weight of an unsaturated carboxylic acid monomer and 50 to 8% of an aromatic vinyl monomer.
9.5% by weight and vinyl cyanide monomer 10-4
The reduced viscosity obtained by polymerizing 9.5% by weight is 0.2 to 0.5.
It is a dl / g copolymer. If the reduced viscosity of the copolymer (C) is less than 0.2 dl / g, the impact resistance is poor, and
If it exceeds dl / g, the fluidity is poor, which is not preferable. In addition,
The reduced viscosity of the copolymer (C) was 30 for the copolymer (C).
℃, dimethylformamide (DMF) solution concentration 0.4
Viscosity measured in g / dl.

The unsaturated carboxylic acid monomer constituting the copolymer (C) includes acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid and the like, and one or more of them may be used. it can. Particularly, methacrylic acid is preferred. As the aromatic vinyl monomer and the vinyl cyanide monomer, the same ones as exemplified in the section of the graft polymer (B) can be used. Further, a part of the aromatic vinyl monomer may be another copolymerizable vinyl monomer, for example, methyl acrylate, ethyl acrylate,
Methyl methacrylate, ethyl methacrylate, 2
-May be substituted with an unsaturated carboxylic acid ester monomer such as ethylhexyl acrylate.

In the production of the copolymer (C), known emulsion polymerization methods, bulk polymerization methods, suspension polymerization methods and solution polymerization methods can be employed, and the emulsifier, initiator, As the various auxiliaries, known ones can be used, and there is no limitation. The method of adding the unsaturated carboxylic acid monomer is not particularly limited, and a method of mixing with another monomer and adding it to the polymerization system, a method of adding it as an aqueous solution, and the like can be adopted. The reduced viscosity of the copolymer (C) can be appropriately adjusted depending on the polymerization temperature, the method of adding the monomer, the type and the amount of the initiator used and the polymerization chain transfer agent such as t-dodecyl mercaptan. it can.

The copolymer (D) used in the present invention
Is a copolymer obtained by polymerizing 50 to 90% by weight of an aromatic vinyl monomer and 10 to 50% by weight of a vinyl cyanide monomer. As the aromatic vinyl monomer and vinyl cyanide monomer constituting the copolymer (D), the same ones as those exemplified in the section of the graft polymer (B) can be used. Further, in the present invention, a part of the aromatic vinyl monomer constituting the copolymer (D) is converted to maleimide, methylmaleimide, ethylmaleimide, N
Maleimide monomers such as -phenylmaleimide, N-cyclohexylmaleimide, O-chloro-N-phenylmaleimide, and unsaturated carboxylic esters such as methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate and 2-ethylhexyl acrylate It may be substituted with a system monomer or the like. The reduced viscosity of the copolymer (D) is not limited at all,
It is preferably in the range of 0.3 to 1.2 dl / g.

In the production of the copolymer (D), known emulsion polymerization methods, bulk polymerization methods, suspension polymerization methods, and solution polymerization methods can be employed.
Known initiators and various auxiliaries can be used without any limitation.

In the present invention, the mixing ratio of the polyamide resin (A), the graft polymer (B), the unsaturated carboxylic acid-modified copolymer (C) and the maleimide-based copolymer (D) is (A) 10 to 80. Parts by weight, (B) 10 to 80 parts by weight, (C) 1 to 40 parts by weight and (D) 0 to 50 parts by weight [provided that the total of (A), (B), (C) and (D) is 1
When the amount is out of this range, the desired composition of the present invention cannot be obtained. Also,
From the viewpoint of the balance of physical properties of the composition, the content of the diene rubber in the entire composition is preferably in the range of 5 to 40% by weight.

The order of mixing the polyamide resin (A), the graft polymer (B), the unsaturated carboxylic acid-modified copolymer (C) and the copolymer (D) and the state thereof are not limited. Depending on the form such as
Examples of the method include the simultaneous simultaneous mixing of the components (A), (B), (C) and (D), and the mixing of the components remaining after premixing the specific two components. For such melt mixing, a Banbury mixer, a roll, an extruder, or the like can be used. In addition, upon mixing, if necessary, polycarbonate, polybutylene terephthalate, polyethylene terephthalate, other thermoplastic resins such as polyphenylene ether, furthermore, an antioxidant, an ultraviolet absorber, a light stabilizer, an antistatic agent, a lubricant, a dye, Known additives such as pigments, plasticizers, flame retardants, release agents, glass fibers, metal fibers, carbon fibers, and metal flakes, reinforcing materials, and fillers can be added.

Hereinafter, the present invention will be described in detail.
It should be noted that the present invention is not limited at all by this. All parts and percentages are shown on a weight basis.

Reference Example 1 100 parts of 1,3-butadiene, 0.3 part of t-dodecylmercaptan, 0.25 part of potassium persulfate, 2.5 parts of sodium rosinate were placed in a pressure vessel.
Parts, 0.1 part of sodium hydroxide and 170 parts of pure water were charged, and after the temperature was raised to 80 ° C., polymerization was started. Polymerization is 10
Finished in time. The obtained diene rubber latex (b-) has a solid content of 37% and a weight average particle size of 0.1.
μ, gel content was 90%. The gel content is
After drying the latex to prepare a film, weighing about 1 g, and immersing in toluene at 23 ° C. for 48 hours,
The insolubles were filtered off and dried with a 100 mesh wire gauze, and the weight% was measured.

Reference Example 2 In a pressure vessel, 270 parts by weight of the diene rubber latex (b-) obtained in Reference Example 1 and 0.1 part of sodium dodecylbenzenesulfonate were added and mixed with stirring for 10 minutes. After that, 5% phosphoric acid aqueous solution 2
0 parts were added over 10 minutes. Then, 10 parts of a 10% aqueous potassium hydroxide solution was added, and a diene rubber latex (b) having a solid content of 34% and a weight average particle diameter of 0.3 μm was added.
-1) was obtained.

Reference Example 3 The enlarged diene rubber latex (b-1) 50 obtained in Reference Example 2 was placed in a pressure-resistant container.
Parts (solid content), 1.5 parts of sodium dodecylbenzenesulfonate, 0.3 parts of potassium persulfate, and 70 ° C.
Then, a monomer mixture composed of 35 parts of styrene and 15 parts of acrylonitrile was continuously added over 5 hours to obtain a graft polymer latex B-1. After adding 1 part of a phenolic antioxidant (Sumitomo Chemical Co., Ltd .: Sumilizer BBM) and 2 parts of trisnonylphenyl phosphite as an antioxidant per 100 parts by weight (solid content) of the obtained latex, magnesium sulfate was used. Then, salting out, dehydration and drying were performed to obtain a graft polymer B-1. In the above polymerization, the diene rubber latex 60
Parts (solid content), 28 parts of styrene and 12 parts of acrylonitrile in the same manner as described above to obtain a graft polymer B-2.

Reference Example 4 After 120 parts of pure water and 0.3 part of potassium persulfate were charged into a pressure vessel, the temperature was raised to 65 ° C. with stirring. Thereafter, a mixed monomer solution consisting of 67 parts of styrene, 30 parts of acrylonitrile, 3 parts of methacrylic acid and 1.5 parts of t-dodecyl mercaptan and 30 parts of an emulsifier aqueous solution containing 2 parts of sodium dodecylbenzenesulfonate were continuously applied for 5 hours each. After that, the polymerization system was heated to 70 ° C. and aged for 3 hours to complete the polymerization. Thereafter, salting out, dehydration and drying were performed using calcium chloride to obtain an unsaturated carboxylic acid-modified copolymer C-1. The reduced viscosity of the obtained copolymer C-1 was 0.3. Further, an unsaturated carboxylic acid-modified copolymer C-2 was obtained in the same manner except that the polymerization of C-1 was changed to 60 parts of styrene, 30 parts of acrylonitrile and 10 parts of methacrylic acid. The reduced viscosity of the obtained copolymer C-2 was 0.32. Furthermore, in the polymerization of C-1, an unsaturated carboxylic acid-modified copolymer Ci was obtained in the same manner except that the amount of t-dodecyl mercaptan was changed to 0.3 part. The reduced viscosity of the obtained copolymer Ci was 0.65.

Reference Example-5 After 120 parts of pure water and 0.3 part of potassium persulfate were charged into a pressure vessel, the temperature was raised to 65 ° C. with stirring. Then, 70 parts of styrene, 30 parts of acrylonitrile, and 0.1 part of t-dodecyl mercaptan were added.
3 parts of a mixed monomer solution and 30 parts of an emulsifier aqueous solution containing 2 parts of sodium dodecylbenzenesulfonate were continuously added over 5 hours each, and then the polymerization system was heated to 70 ° C.
And aged for 3 hours to complete the polymerization. Thereafter, salting out, dehydration and drying are performed using calcium chloride to obtain copolymer D.
-1 was obtained. The reduced viscosity of the obtained copolymer D-1 was 0.1.
It was 6.

[ Examples 1 to 4 and Comparative Examples 1 to 5] Polyamide resin (A), graft copolymers B-1 and B-2, copolymers C-1 and C-2, Ci and The copolymer D-1 was mixed at the mixing ratio shown in Table 1, melt-mixed at 250 ° C. using a 40 mm twin-screw extruder, and pelletized. Then, various test pieces were prepared with an injection molding machine to evaluate physical properties. did. Table 3 shows the results. As the polyamide resin (A) used in the examples and comparative examples, nylon 6 (unitika nylon 6A1030BRL, manufactured by Unitika) was used.

O Impact resistance: according to ASTM D-256. 1/8 inch, 23 ° C. o Fluidity (spiral flow length): Using an Archimedes-type spiral flow mold (3 mmt), set temperature 260 with an injection molding machine (N-140BII manufactured by Nippon Steel Works).
° C., a pressure 1000 kg / cm ^2, to measure the spiral flow length (mm) by an injection rate of 50% for. o Heat resistance: Conforms to ASTM D-648. 1/4 inch, 4.6 kg / cm ² load. o Rigidity: based on ASTM D-790.

[0028]

[Table 1]

[0029]

As described above, the resin composition of the present invention has an excellent balance of impact resistance and fluidity, and has heat resistance,
It is excellent in rigidity and is particularly useful in various applications such as large home appliances and vehicle parts.

Continuation of the front page (72) Inventor Tetsuya Yamamoto 2- 10-2 Kikumoto-cho, Niihama-shi, Ehime Prefecture Sumika ABS Latex Co., Ltd. (72) Inventor Tomoaki Akiyama 2- 10-1 Tsukahara, Takatsuki-shi, Osaka F-Term (in reference) 4J002 BC043 BC063 BC064 BG013 BN15X BN16X CL01W CL03W CL05W

Claims (2)

[Claims] 1. A polyamide resin (A) of 10 to 80 parts by weight, an aromatic vinyl monomer of 50 to 90% by weight and a vinyl cyanide monomer of 10 to 80% by weight in the presence of a diene rubber of 10 to 80% by weight. Monomer mixture 90-2 consisting of 50% by weight
Graft polymer (B) obtained by graft polymerization of 0% by weight
10 to 80 parts by weight, unsaturated carboxylic acid monomer 0.5 to 2
0% by weight, aromatic vinyl monomer 50 to 89.5% by weight
And 1 to 40 parts by weight of an unsaturated carboxylic acid-modified copolymer (C) having a reduced viscosity of 0.2 to 0.5 dl / g obtained by polymerizing 10 to 49.5% by weight of a vinyl cyanide-based monomer, and aroma 0 to 50 parts by weight of a copolymer (D) obtained by polymerizing 50 to 90% by weight of a vinyl group-based monomer and 10 to 50% by weight of a vinyl cyanide-based monomer [provided that (A), (B), The total of (C) and (D) is 100 parts by weight]. 2. A diene obtained by coagulating and enlarging a small particle diene rubber latex having a weight average particle diameter of 0.05 to 0.20 μm to a weight average particle diameter of 0.20 to 0.8 μm. Monomer mixture of 50 to 90% by weight of an aromatic vinyl monomer and 10 to 50% by weight of a vinyl cyanide monomer in the presence of 10 to 80% by weight of a rubber based latex (solid content) The thermoplastic resin composition according to claim 1, wherein the thermoplastic resin composition is a graft polymer obtained by graft-polymerizing a percentage by weight.