MANUFACTURE OF CAPPED POLYCARBONATE FROM BISPHENOL MONOCHLOROFORMATE POLYCARBONATE OLIGOMER

摘要

PURPOSE: To produce an end-capped polycarbonate by using a bisphenol monochloroformate polycarbonate oligomer and a phenol chain terminator. ;CONSTITUTION: Phosgene is introduced into a bisphenol-containing mixture with a pH of 3-11.2 at 15-50°C under interfacial reaction conditions to continue the introduction of phosgene and an alkali metal hydroxide aq. soln. is introduced according to a pH set value predetermined within a pH range of 3-10.5 until pH falls suddenly and, further, 0.0025-0.09 mol of phosgene is introduced per 1 mol of bisphenol and, after stirring is continued until phosgene is not substantially contained, an end-capped phenol compd., 0.05-2 mol of tertiary org. amine per 100 mol of bisphenol and additional alkali metal oxide bringing the pH of the obtained mixture to 9-12 are introduced to obtain the polycarbonate wherein a ratio of a condensed phenol end-capped unit to a condensed bisphenol carbonate unit is 0.05-0.08.;COPYRIGHT: (C)1992,JPO