Polymer scale preventive agent, polymerization vessel for preventing polymer scale deposition, and process of producing polymer using said vessel
AssigneeShin-Etsu Chemical Co., Ltd.
InventorsToshihide Shimizu, Minoru Shigemitsu
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Abstract
A process and coated vessel for use in the prevention of scale adhesion during the polymerization of a monomer having an ethylenic double bond, the two part coating comprising an N-substituted leucophenothiazine dye having the general formula (I): wherein Z is a carbonyl group or a sulfonyl group, R.sup.1, R.sup.2 and R.sup.3 are a hydrogen atom, alkyl group, an amino group, etc., used in conjunction with a vinyl pyrrolidone polymer. The two part coating is used on the inner wall, etc. of a polymerization vessel. Deposition of polymer scale can be effectively prevented, and polymeric product with high whiteness is obtained.
Claims9
A polymerization vessel for polymerizing of a monomer having an ethylenic double bond, said vessel having on its inner wall surfaces a coating for preventing polymer scale deposition, said coating comprising a vinyl pyrrolidone-based polymer and an N-substituted leucophenothiazine selected from the group consisting of N-benzoyl Methylene Blue, N-hydroxybenzoyl Methylene Blue and N-sulfonyl Methylene Blue.
A process of producing a polymer by polymerizing of a monomer having an ethylenic double bond in a polymerization vessel, comprising the step of conducting said polymerization in a polymerization vessel having on its inner wall surfaces a coating preventing polymer scale deposition, wherein the coating comprises a vinylpyrrolidone-based polymer and an N-substituted leucophenothiazine selected from the group consisting of N-benzoyl Methylene Blue, N-hydroxybenzoyl Methylene Blue and N-sulfonyl Methylene Blue.
Dependencies are inferred from the claim text.