Relation between Molecular Weight Distribution and Refining Process of Crude Polyether Polyol Obtained From Propylene Oxid e

Abstract

Polyether polyol prepared by polymerization of propylene oxide with alkaline metal catalyst contains some by-products such as terminal unsaturation compounds, polypropylene glycol and dioxan derivative. The molecular weight distribution becomes broader as polymerization proceeds, because of such by-products. Author investigated the r elation between refining processes and molecular weight distribution of the crude polyether polyol, and confirmed that the combination of migration by heat treatment, acid hydrolysis and rinsing with hot water gave narrow molecular weight distribution. And also, concentration of terminal unsaturation compounds decreases to be nearly zero with those treatments.