Inversion polymerization process for producing vinyl resins using a dual

Abstract

This invention relates to a process of producing vinyl polymers or resins by an inversion polymerization technique in the presence of a dual layer coating on the internal surfaces of the polymerization reactor. By inversion polymerization is meant conducting the polymerization reaction in two stages, in the first or initial stage of which the monomer or monomers being polymerized constitute the continuous phase, and in the second or latter stage of polymerization, water constitutes the continuous phase due to the addition of sufficient water to the reactor to form said phase. The dual layer coating comprises an undercoating or primary coating of (1) the self-condensation product of a polyhydric phenol, or (2) the condensation product of two or more polyhydric phenols, or (3) the self-condensation product of a polyhydric naphthol, said coating being applied from an aqueous alkali metal hydroxide solution thereof, and a top coating comprised of a water-soluble suspending agent, such as an alkyl or an alkyl hydroxyalkyl cellulose ether, said top coating being applied from an aqueous solution thereof. By means of the present invention, polymer buildup on the internal surfaces of the reactor is substantially reduced.