Abstract: A process to prevent scale adhesion on reactor surfaces when polymerizing vinyl monomers. Coating of internal reactor surfaces with a combination of an amino containing aromatic compound, and an alkali metal or ammonium salt of polyvinylsulfuric acid results in the scale prevention. This combination is applied to reactor surfaces via its mixture with a solvent and is subsequently dried to form the coating.

Abstract: The present invention relates to a coating solution for preventing adhesion of polymer scale and a method for preventing scale adhesion during preparation of polymers which can provide polymers having high quality without coloring thereof while preventing adhesion of polymer scale to a polymerizer when a monomer having an ethylenically unsaturated double bond is polymerized. A coating solution for preventing adhesion of polymer scale which comprises anaphthoquinone natural dyestuffs, anthraquinone natural dyestuffs, tannin natural dyestuffs, xanthone natural dyestuffs, flavonoid natural dyestuffs, or/and benzoquinone natural dyestuffs and a polyvinyl alcohol having a degree of saponification of not less than 70 mole % was applied on at least a part of a polymerizer which comes in contact with a monomer having an ethylenically unsaturated double bond and was dried to give a coating film during polymerization thereof.