| 摘要 |
1330761 Recovering polymers from solution SNAM PROGETTI SpA 27 May 1971 [29 May 1970] 17697/71 Heading C3P Polymers are recovered from solution in hydrocarbon solvents by mixing with water and then subjecting the mixture to steam distillation in the presence of a non-ionic biodegrable dispersant for the polymer, thereby obtaining an aqueous dispersion of the polymer. The steam distillation may be effected in two zones, with partial solvent removal in the first and complete solvent removal in the second, the vapourous steam/hydrocarbon mixture discharged from the second zone being used to effect the distillation in the first zone. In examples, 1,4-cis-polybutadiene is recovered from toluene solution, 1,4-cis-polyisoprene from hexane solution and EPDM from toluene solution, the dispersant being either (a) a sucrose glyceride obtained from oxyethylated tallow, (b) an ether of polyethylene glycol with mixed C 11-15 secondary alcohols, or (c) a modified polyethylene oxide known by the trade name "Surfactant CF76". |
