Mobility and orientation of semi-rigid polyesters.
Mobility and orientational behavior of semi-flexible polyesters from diphenyl-dicarbonic acid and some branched propyl- and Bu spacers were investigated using static NMR techniques. Increasing molar mass of the polymers was found to influence the mobility of the rigid parts of the polymer chain while the spacer remains almost unaffected by the d.p. The mobility of the spacer carbons depends, however, on the length of the side chains. Even a magnetic field of 7 T was not able to cause a reasonable macroscopic orientation in most of the samples, probably hindered by the high viscosity of the melts.
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