Aq. phase (co)polymerisation of vinyl chloride - in presence of polymers contg. phosphonic acid gps. to reduce deposits on reactor walls

摘要

The aq. phase polymerisation of vinyl chloride or its copolymerisation with up to 30% of other monomers, catalysed by free radical forming catalysts, is effected in the presence of a polymer where the side chain contains gps. derived from phosphonic acid. The formation of deposits on the walls of the polymerisation reactor is much reduced, the walls can be subjected to about 100 successive charges before they need to be cleaned. Used for emulsion and suspension polymerisation. Typical additives are homopolymers of vinyl phosphonic acid and alkyl phosphonic acid and their copolymers with e.g. (meth)acrylamide, (meth)acrylic acid and carboxylic acid vinyl esters.