This process is a process for production of a vinyl chloride polymer by suspension polymerization or emulsion polymerization of vinyl chloride monomer or a mixture of vinyl chloride monomer with a vinyl monomer copolymerizable with said vinyl chloride monomer in an aqueous medium, characterized in that the polymerization is carried out in a polymerizer, the inner wall surface and portions of the auxiliary equipment thereof which may come into contact with the monomer during polymerization being previously coated with a scaling preventive comprising at least one selected from dyes, pigments and aromatic or heterocyclic compounds having at least 5 conjugated π bonds, while controlling the chloride ion concentration in the reaction mixture to not higher than 100 ppm. According to said process, scaling onto the inner wall surface of a polymerizer, etc. during polymerization can be prevented effectively and surely.
Ueda, Yakugaku Zasshi/Journal of the Pharmaceutical Society of Japan, 1937, vol. 57, p. 185,188
作者:Ueda
DOI:——
日期:——
Method of preventing polymer scale formation
申请人:Shin-Etsu Chemical Co., Ltd.
公开号:EP0355575B1
公开(公告)日:1994-11-02
HETEROCYCLIC COMPOUND AND ORGANIC LIGHT-EMITTING DEVICE INCLUDING SAME
申请人:LT MATERIALS CO., LTD.
公开号:US20220165962A1
公开(公告)日:2022-05-26
The present specification relates to a heterocyclic compound represented by Chemical Formula 1, and an organic light emitting device including the same.