High molecular weight hydroxy-terminated polycarbonates - from thiodiglycol and phosphene or chlorocarbonate esters by interfacial reaction

摘要

Polycarbonates are prepd. by reacting divalent alcohols made up wholly or partly of thiodiglycol with COCl2 or chlorocarboric esters of divalent alcohols and/or phenols by phase interface reactor using conc. aqs. alkali soln. as HCl scavenger, in the presence of inert solvents. The polycarbonates, of mol. wt. 400-20,000, and having units of formula (I) are also clamed. Used as plasticisers and lubricants, but mainly as starting materials for the prepn. of polyurethane elastomers with excellent mechanical properties. The process avoids formation of undesirable by-prods. arising from hydrolysis of phosgene or chlorocarbonic ester gps. and gives high mol. wt. polycarbonates in high yields.