Polymerization process

Abstract

A process for the production and treatment of a stereoregular propylene polymer such as isotactic polypropylene. The isotactic polypropylene can be produced by catalysis employing a metallocene catalyst or employing a Ziegler-Natta catalyst. A polymerization reactor is operated to provide for the reaction of propylene supplied to the reactor to produce a stereoregular propylene polymer fluff. A product stream containing unreacted propylene and the propylene polymer fluff is withdrawn from the polymerization reactor. The product stream is treated to separate at least a portion of the unreacted propylene from the product stream. The polymer fluff is heated to a temperature sufficient to melt the propylene polymer. Incorporated into the propylene polymer fluff in an amount within the range of 0.01-0.08 wt. % is a tertiary amine formula: wherein R is an aliphatic group containing 8-18 carbon atoms and R′ and R″ are each independently a hydroxyalkyl group containing from 1 to 3 carbon atoms. Thereafter, the heated polymer fluff containing the tertiary amine is extruded to produce particles of the propylene polymer.

Dependencies are inferred from the claim text.