The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 01, 1994
Filed:
May. 19, 1993
Tadashi Amano, Kamisu, JP;
Shuji Ohnishi, Lake Jackson, TX (US);
Minoru Shigemitsu, Kamisu, JP;
Yasuhiro Takahashi, Kamisu, JP;
Hajime Kitamura, Ichihara, JP;
Shin-Etsu Chemical Co., Ltd., Tokyo, JP;
Abstract
An apparatus for continuous polymerization of vinyl chloride or a vinyl chloride-based monomeric mixture, comprising a pre-mixer 1 for preparing an aqueous suspension of the vinyl chloride or vinyl chloride-based monomeric mixture, and a polymer slurry tank 5 connected to the pre-mixer 1 through a polymerization passage comprising a piping 3, wherein a pump comprising a conical hub and an impeller mounted thereon comprised of a single spiral blade is used for drawing out the aqueous suspension from the pre-mixer into the polymerization passage and for discharging a polymer slurry formed in the passage into the slurry tank, and the polymerization passage has a length sufficient for permitting the vinyl chloride or vinyl chloride-based monomeric mixture contained in the aqueous suspension flowing through the passage to be polymerized to a predetermined extent while passing through the passage. The use of the pump having the structure as above ensures a marked suppression of polymer scale deposition in the pump, heat exchanger and pipings, and makes it possible to produce a resin with few fish-eyes. The apparatus is of extremely high industrial value for carrying out continuous polymerization.