Polymer scale deposition preventive agent

摘要

A polymer scale deposition preventive agent for use in polymerization of a monomer having an ethylenically unsaturated double bond, comprising an alkali metal salt and/or ammonium salt of a sulfonation product of a condensate comprising (A) an aromatic amine compound and (B) an aldehyde compound as essential condensation components. Deposition of polymer scale in a polymerization vessel can be effectively prevented, not only on the areas in the liquid-phase region but also on the areas around the interface between the gas phase and the liquid phase. Products such as sheets formed from the polymeric product have very few fish eyes, and have very little initial discoloration, and therefore are of high quality. The use of the agent makes it unnecessary to remove polymer scale for every polymerization run, thereby improving productivity.