Process for preparing low inherent viscosity-high glass transition agents as an overpolymer on polyvinyl chloride resins

A process for treating a polyvinyl chloride resin, comprising the steps of:

• adding one or more polyvinyl chloride high glass transition temperature agent forming monomers to a polyvinyl chloride particulate resin contained in water, wherein amount of said polyvinyl chloride resin is from about 50 to about 2,000 parts by weight for every 100 parts by weight of said one or more monomers and wherein said one or more monomers are selected from the group consisting essentially of styrene-type monomers, vinyl nitriles, maleimides, indenes, norbornenes, unsaturated acid anhydrides, and mixtures thereof,
• adding from about 0.005 parts to about 4 parts of a substantially water insoluble chain transfer agent to said water and polyvinyl chloride particulate resin per 100 parts by weight of said one or more monomers, and
• suspension polymerizing in absence of a suspending agent said glass transition temperature agent forming monomers in the presence of said substantially water insoluble chain transfer agent so that said treated polyvinyl chloride resin has a reduced inherent viscosity.