JPH047393B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a polyphenylene sulfide resin (hereinafter abbreviated as PPS resin) composition which has greatly improved weather resistance. PPS resin has excellent heat resistance, chemical resistance, and mechanical strength, and is widely used as an engineering plastic in electrical and electronic parts, automobile parts, mechanical parts, structural parts, etc. However, one of the drawbacks of this PPS resin is its poor weather resistance. When PPS resin is exposed to direct sunlight outdoors, there is little loss in strength, but the surface becomes rough in a relatively short period of time, causing problems such as glass fibers coming to the surface and causing discoloration. Until now, there was no known method to improve the weather resistance of PPS resin, and the company had no choice but to give up on using it in applications exposed to direct sunlight, such as exterior parts. Therefore, there has been a strong desire to improve the weather resistance of PPS resin. As a result of intensive studies focusing on this point, the present inventors discovered the surprising fact that weather resistance can be significantly improved by adding a specific amount of copper oxide and/or sulfide. , we have arrived at the present invention. The present invention will be explained in detail below. The PPS resin used in the present invention has the general formula
(1) Uncrosslinked products, such as Phillips Petroleum's Ryton V-1, or partially crosslinked products, such as Ryton P, by heat treatment.
-4, P-6, R-6, etc. are used. These raw PPS resins can be mixed and used depending on the purpose. Next, the copper oxide powder used in the present invention is as follows:
Examples include cuprous oxide and cupric oxide, and cupric oxide is particularly desirable from the viewpoint of stability. Further, examples of the copper sulfide powder include cuprous sulfide and cupric sulfide. The average particle diameter of these powders is preferably 1 to 300 microns. If it exceeds 300 microns, problems such as a decrease in strength will occur when it is made into a molded product. The amount added is selected within the range of 0.1 to 100 parts by weight. If it is less than 0.1 part by weight, the effect of improving weather resistance will be weak;
If it exceeds 100 parts by weight, although the weather resistance is good, the PPS resin will undergo a crosslinking reaction, the viscosity will increase, and molding will become difficult, so it is not practical. These copper oxide and copper sulfide powders can sufficiently exhibit their effects even when used alone or in a system in which they are mixed in any proportion. Although the composition of the present invention is not an essential component other than the PPS resin and copper oxide and/or copper sulfide, it is also possible to add various fillers. For example, fibrous substances such as glass fibers and carbon fibers, and whiskers such as potassium titanate, silicon nitride, zirconia, alumina, and gypsum are used to improve mechanical strength and weather resistance.
In addition, calcium carbonate, talc, clay, silica, mica, alumina, glass beads,
titanium oxide, carbon black, graphite,
Inorganic fillers such as molybdenum disulfide and organic polymer materials such as fluorine resins, polyamides, polyesters, and polyimides can also be used. A method for producing the composition of the present invention is to mix and knead PPS resin, copper oxide and/or copper sulfide, and filler as necessary using an ordinary single-screw or twin-screw extruder to form pellets. Adopted. The pellets thus obtained are usually molded into molded bodies of various shapes by injection molding. Alternatively, extrusion molding can be used to create pipes, profile extrusions and T.
It is also used to form films and sheets using dies. It has been common knowledge that copper compounds are extremely harmful to polymeric materials by accelerating their decomposition, as is commonly referred to as copper poisoning, but the present invention is extremely unique and overturns this common sense. , its mechanism of action is completely unknown. The composition of the present invention has an extremely large effect as it opens a new way for applications such as exterior parts that were previously considered impossible for PPS resin. The present invention will be specifically explained below using Examples. Examples 1 to 3 6 kg (100 parts by weight) of Ryton P-4 manufactured by Phillips Petroleum as PPS resin, length 3 mm
4Kg (66.7 parts by weight) of chopped glass fiber and 0.06Kg (1 part by weight), 0.3Kg (5 parts by weight), and 0.6Kg (10 parts by weight) of cupric oxide powder (manufactured by Wako Pure Chemical Industries) were added. After uniformly mixing with a mixer,
Kneading and pelletizing were carried out using a 40 m/m single screw extruder. The obtained pellets were molded into strip-shaped specimens of 3 x 25 x 120 mm using a 1-ounce injection molding machine at a mold temperature of 130°C.
It was made with This test piece was placed on an outdoor exposure stand facing south at an angle of 35°, and an outdoor exposure test was conducted for 6 months. The results are shown in Table-1. Comparative Example 1 A test piece was prepared in the same manner as in Example 1 without adding copper oxide, and an outdoor exposure test was conducted for the same period. The results are shown in Table-2. Comparative Example 2 A test similar to Example 1 was conducted except that the amount of cupric oxide powder was changed to 3 g (0.05 parts by weight). The results are shown in Table-2.

[Table] ×: Significantly worsened

[Table] Examples 4 to 6 The same tests as in Examples 1 to 3 were conducted except that cupric oxide was replaced with cupric sulfide powder (manufactured by Wako Pure Chemical Industries, Ltd.). The results are shown in Table-3.

【table】

Claims (1)

[Claims] 1. A polyphenylene sulfide resin composition with excellent weather resistance, which contains 0.1 to 100 parts by weight of copper oxide and/or sulfide to 100 parts by weight of polyphenylene sulfide resin.