Preparation and properties of branched polybutylenesuccinate

To obtain long branched polybutylene succinate (PBS), modified PBSs were pr epared by introducing a branching agent, trimethylol propane (TMP), to the polycondensation system of succinic acid and 1,4-butanediol. Molecular para meters such as absolute molecular weight and root-mean-square (RMS) radius of the modified PBSs were measured by gel permeation chromatography (GPC) w ith a multiangle laser light-scattering (MALLS) detector. The RMS radius of TMP05, PBS prepared by incorporating 0.5 wt % TMP during polycondensation, was the smallest of all PBSs tested at the same molecular weight. The nota ble shear thinning and much reduced loss tangent for TMP05 qualitatively su pported the difference in their molecular structures predicted by GPC. The analytical results indicated that introducing 0.5 wt % TRIP produced PBS wi th chain branches long enough to produce molecular entanglements. (C) 2001 John Wiley & Sons, Inc.