Mean-square radius of gyration and second virial coefficient of poly(diisopropyl fumarate) in dilute solution

Abstract

The mean-square radius of gyration (S2) and second virial coefficient A2 were determined from light scattering measurements for 13 samples of poly(diisopropyl fumarate) (PDiPF), each with the fraction of racemo diads fr = 0.22, in a range of weight-average molecular weight from 4.02 × 104 to 8.59 × 105 in tetrahydrofuran at 30.0°C. From a simultaneous analysis of the present data for (S2) and A2 on the basis of the Kratky-Porod (KP) wormlike chain with excluded volume, the KP model parameters for PDiPF, i.e., the stiffness parameter λ-1 and the shift factor ML are determined to be 113 Å and 89Å-!, respectively, the ML value being consistent with that estimated on the basis of chain conformations of PDiPF. The λ-1 value indicates that PDiPF is stiffer than typical flexible polymers but not so stiff as typical semiflexible polymers such as poly(n-hexyl isocyanate). ©2008 The Society of Polymer Science.