Aromatic polyester and polyester-carbonate polymers are isolated - from soln. in organic solvent by adding small amt. of organic non-dissolver then adding to water while stirring at high circumferential velocity

摘要

The polymers are isolated from their solns. (in an organic solvent (II)) by (1) treating soln. of (I) with small amt. of organic non-dissolver (III) then (2) metering soln. into water with simultaneous stirring at high circumferential velocity, opt. with addn. of (III) and water. ((III) has higher b.pt. than (II) and is miscible with it but not with water. (I) have (wt. average) mol.wt. 10,000-100,000, (II) is CH2Cl2 (IV), (III) is n-hexane, n-heptane, n-octane, or cyclohexane, (Wt.) ratio water to (III) is 10:1-0.5:1, (Wt.) ratio (I) to (III) is 1:10-0.5:1. Circumferential velocity is 50,000-200,000 cm/minute. (I) are pptd. at 40-80 deg.C. Pptd. (I) have particle size 10-1000 microns. ADVANTAGE - (I) are obtd. as fine particles instead of as compact blocks and contain only very low amts. of