Patent ID: 7439311

Claim:
A method for producing a polymer comprising polymerization in a polymerization reactor having an inner wall covered with an anti-fouling agent comprising an aqueous solution having a pH of 9 or greater and containing a polyvinyl alcohol obtained through saponification of a polyvinyl ester that contains monomer units having a silyl group of formula (1): wherein R 1 represents an alkyl group having from 1 to 5 carbon atoms; R 2 represents an alkoxyl or acyloxyl group optionally having an oxygen-containing substituent; and m indicates an integer of from 0 to 2, wherein the polyvinyl alcohol satisfies the following formulae (I) and (II): 370 <P×S< 9000 (I) wherein P indicates the viscosity-average degree of polymerization of the polyvinyl alcohol, and S indicates the content (mole %) of the monomer units having a silyl group of formula (1) in the polyvinyl alcohol; 0.2/100≦( A−B )/( B )≦75/100 (II) wherein A indicates the content (ppm) of silicon atoms in the polyvinyl alcohol, and B indicates the content (ppm) of silicon atoms in the polyvinyl alcohol that was washed with sodium hydroxide-containing methanol and then washed with methanol by Soxhlet extraction, wherein A and B are measured by ICP emission spectrometry after ashing of a sample.