Patent ID: 7005496
Filing Date: 2006-02-28
Classification: C07D

Abstract:
1. A process for producing trimethylene carbonate from poly(trimethylene carbonate) which comprises: (a) introducing liquid poly(trimethylene carbonate) and an optional catalyst into a wiped film evaporator reactor under a vacuum of about 112 kPa or less, preferably about 15 kPa or less, said reactor having walls heated to at least about 230° C. and an internal condenser heated to a temperature above the boiling point of trimethylene carbonate, (b) spreading the poly(trimethylene carbonate) into a thin film and allowing it to flow down the interior surface of the heated walls, (c) depolymerizing the poly(trimethylene carbonate) to form trimethylene carbonate which is volatilized and condenses on the internal condenser and residual poly(trimethylene carbonate) which continues down the reactor, and (d) collecting the trimethylene carbonate in a cooled distillate receiver.