Process for removal and recovery of unreacted monomers from resinous polymers

Claim 1

In the process for producing a monomerfree resinous polymer wherein said polymer is prepared by the emulsion polymerization of a major portion of a monounsaturated nitrile and optionally another monovinyl monomer copolymerizable therewith, in an aqueous medium and optionally in the presence of a preformed diene rubber which may be a homopolymer or a copolymer of a conjugated diene monomer, and wherein the polymeric latex prepared in said polymerization reaction is coagulated, the resulting coagulum is hardened and washed with water, and the essentially monomer-free resinous polymer recovered therefrom, the improvement comprising: removing and recovering unreacted monomer from the coagulated latex of said polymer during the hardening and washing steps of the process by: A. heating a slurry of the monomer-containing coagulum of said polymer in an aqueous bath maintained at a temperature in the range of from about 10°C above to 10°C below the heat distortion temperature of the polymer, to set the polymer and to remove some of the monomer therefrom; B. partially dewatering the coagulum from (A);