BigPatents India

The invention relates to the evaporation of a viscous polymer solution having at least 30 wt.%, preferably at least 50 to 70 wt.%, solvents and monomers. According to the inventive method, the polymer solution to be evaporated is guided through a heated helical tube (5) as a film flow with a vapor exit velocity ranging from 200 to 300 m/s and flows into a heated separator (6) afterwards. Heating of the helical tube (5) and of the separator (6) is realized in such a way that the temperatures of the heating means in the helical tube (5) and in the separator (6) are above the softening point of the polymer. An additional important method criterion is characterized in that the two-phase mixture which is made of a polymer melt, solvent vapors, and monomer vapors and which is formed in the helical tube (5) is relieved to a pressure ranging from 10 mb to 800 mbabs in the heated vapor separator (6). Drawing: 03 Sheets. Total Pages: 17 (FIG. 01)