PROCESS FOR RECOVERING VINYL POLYMERS FROM EMULSCIR PELYMERIZATION LATICES

摘要

Polymerization of vinyl or vinylidene halides comprises forming a monomer premix in an aq. medium with a free radical initiator and an emulsifier and then homonizing the premix. The premix is polymerized at a temp. of 30-70oC at pH 3-12 to produce vinyl polymer latex in a reaction zone. The latex is then stripped by steam from an unreacted monomer and a coagulating agent is added to the latex at pH 2-8 to form a slurry of friable agglomerates of polymer particles in serum. The serum is removed under pressure through a permeable membrane and a wet cake polymer is obtd. and rinsed of residual compds. The wet cake is crumbled to form friable polymer agglomerates and particles, then heated air is injected at 50-80oC and 2.5-80 psig. into the mill.