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:
Mar. 18, 1997
Filed:
Dec. 27, 1994
Takuya Ueda, Kamisu-machi, JP;
Kikuo Nakajima, Hasaki-machi, JP;
Yoichi Tanifuji, Kamisu-machi, JP;
Tadashi Amano, Kamisu-machi, JP;
Shuji Ohnishi, Kamisu-machi, JP;
Shin-Etsu Chemical Co., Ltd., Tokyo, JP;
Abstract
A vinyl chloride polymer is produced by subjecting vinyl chloride or a monomer mixture made up mainly of vinyl chloride to suspension polymerization in an aqueous medium using a polymerization apparatus equipped with a polymerization vessel. The polymerization apparatus used comprises a polymerization vessel (1) having a substantially cylindrical inner space, said inner space of said polymerization vessel being provided with a plurality of baffles (5) comprising vertically extending pipes, and serpentine pipelines (6) each of which is placed between two adjacent baffles and is extended in a serpentine fashion along the polymerization vessel inner wall from the lower part to the upper part of the polymerization vessel, and a refrigerant being passed through said baffles and said serpentine pipelines. High-cooling performance can be obtained, a high-speed reaction in a large-sized polymerization vessel becomes possible, and a stable polymerization reaction can be carried out. A high-quality and uniform polymer that has few fish eyes and has a high bulk specific gravity can be obtained.