Chain fragmentation and fragment diffusion at the glass transition

Abstract

Polymer chain diffusion was measured by SANS using a new technique. The chains of a copolycarbonate were fragmented, in blends with tetramethylpolycarbonate, in the glassy state, so that the split chains remained first conformationally intact. The subsequent diffusion of the chain fragments alters the structure factor of the blend. This was monitored by SANS and interpreted in terms of center-of-mass diffusion.