Polycarbonates from the 2,2,4,4-tetramethylcyclobutane-1,3-diols

The preparation of a series of polycarbonates of high molecular weight from the cis- and the trans-2,2,4,4-tetramethylcyclobutane-1,3-diols is described. Methods were established for determining the ratio of trans- to cis- repeat units in the polymers and the nature of an extensive side reaction producing carbon dioxide and 2,2,4-trimethyl-3-pentenal was investigated.