A process for separating volatile materials from liquid mixtures, the polymers and contain constituents volatile

摘要

Volatile constituents are separated from a liquid composition containing polymer by feeding the composition to the upper portion of a chamber maintained at a pressure below the vapour pressure of the feed to flash vaporize the volatiles and foam the composition thereby releasing sufficient volatiles to enable a foamed strand of polymer to be concurrently formed freely descending within the chamber without deposition of polymer on the chamber walls, the strand being contacted with the surfaces of a pair of counter-rotating rollers or belts within the chamber and having a nip clearance in excess of that necessary for mechanical clearance and less than the thickness of the strand, the surfaces of the rollers or belts moving, at the zone of contact, with the flow of the strand so as to draw the strand through the nip to mechanically compress the strand to effect a further release of volatiles and convey the devolatilized polymer composition from the chamber. The polymer composition may be polystyrene dissolved in its monomer. Figures (not shown) are given of an apparatus for carrying out the above process. missing page 282