Styrene → Butyl prop-2-enoate;styrene

Participants

Reaction Conditions

Reaction Steps

A 500 ml. glass polymerization vessel equipped with a refulx condenser, a dropping funnel, a thermometer and a stirrer was charged with 110 parts of a 5.7% aqueous solution of sodium N-sulfoisobutyleneacrylamide/vinyl acetate copolymer (molar ratio: 10/90, [η]: 1.13 dl./g.) (hereinafter referred to as "copolymer A") as an emulsifier and 10 parts of a 10% aqueous solution of dissodium hydrogenphosphate as a pH controlling agent, and the temperature was raised to 70° C. with stirring at a rate of 200 r.p.m. To the vessel were then added 6 parts of butyl acrylate, 6 parts of styrene and 3.1 parts of a 4% aqueous solution of potassium persulfate to initiate emulsion polymerization. After initial polymerization at that temperature for 30 minutes, the polymerization was further continued at 75° C. for 4 hours, while continuously adding dropwise 53 parts of butyl acrylate and 53 parts of styrene over 4 hours and adding 9.4 parts of a 4% aqueous solution of potassium persulfate in two portions. The reaction mixture was further maintained at 75° C. for 1.5 hours to complete the polymerization to give an emulsion of butyl acrylate/styrene copolymer.

Provenance & Evidence