An Investigation of the Possibility of Diameter Reduction for Polystyrene and Styrene-Divinylbenzene Copolymer Granules Obtained Suspension Polymerization

摘要

The reduction in the mean diameter of polystyrene and styrenedivinylbenzene copolymer granules, brought about by suspension polymerization has been investigated. For this purpose, emulsifiers containing hydrophilic polyethlene glycol fragments were added to a stabilizer [starch, poly(vinyl alcohol) or polymethacrylic acid with 10 mol% methylmethacrylate units]. The emulsifiers investigated such as 'Stearox' (20s-oxyethylated stearic acid), 'Phenoxol' (15s-oxyethylated phenol) and 'APhO' (10s-oxyethylated alkylphenol) were found to reduce the mean diameters of granules by a factor of 10 or more. The same tendency was observed when benzoyl peroxide was replaced by the surface-active oligomeric peroxide of sebacinic acid whose surface activity is due to the polymeric chain ends.