JPS63273665A - Polyphenylene sulfide resin composition - Google Patents

Abstract

PURPOSE:To obtain a polyphenylene sulfide resin composition having excellent heat resistance and high density, low wearability, colorable possession of antistatic effects, by blending a polyphenylene sulfide resin with zinc oxide obtained by wet method, having a specific average particle diameter. CONSTITUTION:(A) 100pts.wt. polyphenylene sulfide resin containing >=70mol.% unit shown by the formula preferably obtained by reacting sodium sulfide with p-dichlorobenzene in an amine solvent or sulfone solvent is blended with (B) 400-2,000pts.wt. zinc oxide produced by wet method wherein zinc oxide which was used as a catalyst for chemical reaction is washed with water and calcined at 500-700 deg.C to grow particles sizes into 1-10mum, preferably 2-8mum, further subjected to surface treatment by a silane coupling agent, etc., optionally with a lubricant, an oil, pigment etc., to give a composition having 10<5>-10<10>OMEGA.cm volume specific resistance.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention uses 1-10 μm steel, preferably 80-95-1% zinc oxide produced by a wet process with an average particle size of 2-8 μm.
, preferably 83 to 90 wt%, and the volume resistivity is 1.
0' to 101Ω・C11, the molded product made of the material according to the present invention has an antistatic effect, simplifies the mechanical structure in which the molded product is incorporated, and reduces mold wear. The present invention provides a polyphenylene sulfide resin composition with a specific gravity at a low cost.

[Prior art]

Conventionally, parts that require a certain degree of specific gravity have been processed and used from metal having the desired specific gravity.

However, in order to reduce the price of products, plastics filled with ferrite-filled plastic molded products have become expensive (problematic) due to the high processing costs required to process them into the desired shape. In addition, using zinc oxide, which has a specific gravity similar to that of ferrite, can increase the specific gravity and reduce metal wear, but the molded product becomes an insulator and has no antistatic effect. Generally, this was compensated for by adding a conductive substance such as carbon.This resulted in a black or gray color, making dual coloring impossible. In this case, the ferrite itself was dark brown, so it was not possible to color it freely.

To solve the above problem, Japanese Patent Application Laid-Open No. 62-16280
Attempts were made to use polyamide as a resin. Recently, as electrical and electronic equipment has become smaller and airtight, the internal temperature has increased, up to 120°C.
It has become difficult for polyamides to meet the demands for heat resistance of up to 150°C, and higher heat resistance of 180°C.

[Purpose of the invention]

The present invention is a conventional high specific gravity plastic molding material with a volume resistivity of 10% to 101°Ω・C-, which has an antistatic effect, can be colored, has stable moldability, and has low mold wear. However, as a result of research to obtain a material that satisfies the above requirements, we found that a material with an average particle diameter of 1 to 10μ, preferably 2 to By mixing 8 μm zinc oxide,
We have obtained the knowledge that it is possible to impart an antistatic effect. Furthermore, by using polyphenylene sulfupide as a resin, we found that it can withstand heat up to 200"C. Based on these findings, we conducted various research and completed the present invention. be.

[Structure of the invention]

The present invention is based on polyphenylene sulfide resin (later PP).
(referred to as S)), the average particle diameter is 1 to 1.
Zinc oxide obtained by wet method at 0 μm 400-20
00 parts by weight, the volume resistivity is 105 to 101°Ω・0, and there is little mold wear.
Our goal is to provide PPS&ll compositions with high heat resistance.
Zinc oxide used in the present invention is heated at 500 to 700°C after washing the zinc oxide used as a catalyst for chemical reaction with water.
A material produced by a wet method is used in which the grain size is grown to 1 to 10 μm, preferably 2 to 8 μm by calcining.

The particle size! When the particle size is less than μ, the volume resistivity becomes large and the antistatic effect is lost, and when the particle size exceeds 10 μ, the mechanical strength, especially Iil! It is useless as a product due to its extremely low strength.

Furthermore, since the particle size affects the contact area with the resin and changes the specific gravity, it is necessary to reduce the variation in particle size.

The PPS used in the present invention preferably contains 70 mol% or more of the structural unit represented by the general formula (To); if the amount is less than 70 mol%, it is difficult to obtain a composition with excellent properties.
Methods for polymerizing this polymer include polymerizing p-dichlorobenzene in the presence of sulfur and sodium carbonate, polymerizing p-dichlorobenzene in the presence of sodium sulfide or sodium hydrosulfide in a polar solvent, and polymerizing p-chlorothiophenol in the presence of sodium sulfide or sodium hydrosulfide. Examples include self-condensation, but suitable methods include reacting sodium sulfide and p-dichlorobenzene in an amide solvent such as N-methylpyrrolidone or N,N-dimethylacetamide or a sulfonic solvent such as sulfolane. be. At this time, in order to adjust the degree of polymerization, it is preferable to add an alkali metal salt of carboxylic acid or sulfonic acid, or add an alkali hydroxide.
If it is less than mol%, it is a meta bond (kai S-), an ether bond (發＠＠-5-), a sulfone bond (發士２社S-)
, biphenyl bond (-@@-3-), Tl-substituted phenylsulfphenyl, alkoxy group, carboxylic acid or metal base of carboxylic acid, )trifunctional phenyl sulfide bond (-g=), etc. The amount of the copolymerizable component is preferably 10 mol % or less, although the amount may be within a range that does not significantly affect the crystallinity of the polymer.

In particular, when selecting trifunctional or higher functional phenyl, biphenyl, naphthyl sulfide bonds, etc. for copolymerization, 3 mol% or less,
More preferably, it is 1 mol% or less.

As a specific method for producing such PPS, for example, (1
) Reaction between halogen-substituted aromatic compounds and sulfurized alkalis (
U.S. Patent No. 2,513,188, Japanese Patent Publication No. 44-27
671 and Special Publication No. 45-3368), (2
) Condensation reaction of a number of thiophenols in the coexistence of an alkali catalyst or copper salt (see US Pat. No. 3,274,165, British Patent No. 1,160,660), (3) Condensation reaction of an aromatic compound and sulfur chloride in the coexistence of a Lewis acid catalyst. condensation reaction (
Special Publication No. 46-27255, Belgian Patent No. 29437
), and can be selected arbitrarily depending on the purpose. Currently, it is being offered on the market as a product by Philips Petrium under the trade name "Rydon."

The above zinc oxide is added in an amount of 400 to 3100 parts by weight of PP.
Fill PPS with 2000 parts by weight to the required specific gravity. Since zinc oxide has a high specific gravity, in order to reduce weight variation, the variation in filling amount must be within 5 parts by weight.

The surface of zinc oxide is modified with a surface modifier such as a titanate coupling agent or a silane coupling agent before being mixed with PPS. In addition, to improve moldability, stearic acid-based lubricants such as barium stearate, calcium stearate, lead stearate, and lithium stearate, olefin oil, and silicone oil are added at 0.05%.
~0.5% may be added.

Furthermore, zero or more pigments may be added depending on the purpose, and the mixture is kneaded with an extruder at a temperature of 270° C. to 320° C. to obtain a mixture having the above composition.

〔Effect of the invention〕

According to the present invention, while having low wear and antistatic effect,
It is possible to obtain colored molded products. Conventionally, low-wear materials have the disadvantage that they are insulating, and that they can only be made black by adding a conductor such as carbon, and materials with antistatic effects cannot be made with gold. The drawback of large mold wear is eliminated, and by using PPS, it can be used even in areas with high temperatures of up to 200°C, and is advantageous for precision and miniaturization.

Example 1 As a comparative example, ferrite (Toda Industries, C
P-300), and as an example of the present invention, zinc oxide (Hakusui Chemical type, Zinc White S) was kneaded using an AS-30 extruder manufactured by Nakatani Kikai (cylinder temperature 260-320°C) to obtain pellets. .

Next, the above pellets were dried in a hot air dryer at 150°C for 4 to 5 hours, and the pellets were dried in an injection molding machine (barrel temperature 290 to 350°C).
, mold temperature 120-150℃, injection pressure 900-150
0 kg/c+1), a molding test method was created, and its physical properties were measured. The physical properties are shown in Table 1.

Example 2 PPS ("Rydon" PPS% P-6) was kneaded with several types of zinc oxide using an AS-30 extruder manufactured by Nakatani Kikai to obtain pellets.

Next, the above pellets were dried in a hot air dryer at 150°C for 4 to 5 hours, and injection molded a (barrel temperature, 290 to 350°C).
, mold temperature 120-150℃, injection pressure 900-150℃
0 kg/cd) to create a molding test force, and the physical properties are shown in Table 21.

Table 1 Comparison of ferrite and zinc oxide
ooo Evaluated by weight change after shot.

Table 2 Comparison of zinc oxide

Claims (1)

[Claims] A colorable polyphenylene sulfide resin composition comprising 400 to 2,000 parts by weight of zinc oxide obtained by a wet process and having an average particle diameter of 1 to 10 μm to 100 parts by weight of the polyphenylene sulfide resin.