Method of making styrene-type polymer comprising suspension polymerization conducted in aqueous medium containing combination of polyvinyl alcohol and sulfonated polystyrene or sulfonated styrene-maleic anhydride copolymer

Abstract

There is described a method of making a styrene-type polymer composition which comprises a step of suspension polymerizing a styrene-type monomer composition in an aqueous medium comprising water, polyvinyl alcohol and a water-soluble sulfonated polystyrene, a water-soluble sulfonated styrene-maleic anhydride copolymer or a mixture thereof. Optionally, the styrene-type monomer composition may contain a rubbery material as a toughening agent. Optionally, the suspension polymerization step may be conducted subsequent to a prepolymerization step conducted in mass.

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