Shin-etsu Chemical Co., Ltd.

Tatsuya Fujimoto

Toshihide Shimizu

Seiji Fukuda

Tadashi Amano

Ken Yahata

Ichiro Kaneko

Mikio Aramata

Tetsuya Inukai

Ryuichi Saito

Makoto Fujiwara

Hajime Ishizaka

Masahiro Yuyama

A thermally expandable vinyl chloride resin composition is provided. It includes (A) 100 parts by mass of a vinyl chloride resin, (B) 5 to 200 parts by mass of an inorganic filler, (C) 10 to 300 parts by mass of a thermally expandable graphite, (D) 0.1 to 10 parts by mass of a fluororesin, and (E) 10 to 300 parts by mass of a phosphorus compound. The composition exhibits favorable thermal expansion properties and favorable shape retention following thermal expansion upon exposure to high temperatures.

Vinyl chloride resin composition and molded article thereof

The present invention provides an antistatic agent for vinyl chloride-based resins which can impart superior antistatic properties to the vinyl chloride-based resin, and which can thereby solve various problems arising from charging of the vinyl chloride-based resin with static electricity, a vinyl chloride-based resin composition containing this antistatic agent, and a method for manufacturing this composition. The present invention provides an antistatic agent for vinyl chloride-based resins which consists of silica particles containing at least 99.0% by mass of SiOand 0.00005% 80.5 ppm by mass or less of sodium, and which has such a particle size distribution that at least 98% by mass of the silica particles is occupied by the particles having a particle diameter in the range from 30 to 1,000 nm.

Antistatic agent for vinyl chloride-based resins, vinyl chloride-based resin composition containing the same, and method for manufacturing this composition

There is provided a polymer scale deposition preventive agent, comprising an alkaline solution of a condensation product having a molecular weight of 500 to 1,000,000 obtained by condensing a dimer compound of 2,3-dihydroxynaphthalene with formaldehyde. By polymerizing vinyl chloride or a monomer mixture containing vinyl chloride in a polymerization vessel wherein a coating film made of said polymer scale deposition preventive agent has been formed on the inner wall surface and the like, polymer scale is effectively prevented from depositing not only on an agitation apparatus but also on areas near the interface between a gas phase and a liquid phase, which prevention of the polymer scale deposition is conventionally difficult. Thus, a vinyl chloride polymer can be obtained which contains colored foreign matters, fish eyes, etc. in small amounts and is small in initial discoloration and is good in quality.

Composition comprising condensation product of dimer of 2,3-dihydroxynaphthalene and formaldehyde for polymerization

When oganohalosilanes are prepared by charging a reactor with a contact mass containing metallic silicon and a copper catalyst and introducing an organohalide-containing gas into the reactor to effect the direct reaction, 50-10,000 ppm of bronze phosphide is added to the contact mass. The invention is successful in efficiently producing organohalosilanes in a high STY and low T/D.

Preparation of organohalosilanes

Process of producing vinyl chloride polymer by using condensation

A process for producing a vinyl chloride polymer by polymerizing a monomer comprising vinyl chloride by suspension polymerization in a polymerization vessel on the inner wall surface of which a coating of a polymer scale preventive agent is formed, comprising the steps of applying a high-speed shearing force to a mixture comprising water, the monomer, a polymerization initiator, and (A) a dispersant comprising a partially saponified polyvinyl alcohol having a specified average degree of polymerization and a specified degree of saponification plus (B) a dispersant comprising a hydroxypropylmethylcellulose which has a specified methoxyl substitution degree, a specified hydroxypropoxyl substitution degree, and a specified viscosity and subjecting the mixture to said suspension polymerization. A vinyl chloride polymer having an average particle diameter of 200 to 600 .mu.m and a narrow particle size distribution and excellent in plasticizer take-up, etc. is provided.

Growing community of inventors

Kamisu, Japan

Tatsuya Fujimoto