Estimation of conformational characteristics of bisphenol-A based poly(hydroxyethers)

Two samples of bisphenol-A based epoxy resins (poly(hydroxy ethers)) were f ractionated by precipitation. The fractions were characterized by the weigh t-average molecular weight (1.3 < M-w 10(-3) < 40) and the intrinsic viscos ity in tetrahydrofuran and chloroform. Theories based on the worm-like touc hed-bead model were used to treat the molecular-weight dependence of the in trinsic viscosity and to estimate the conformational characteristics (Kuhn statistical segment length l(K), Flory characteristic ratio C-infinity, and steric factor sigma). Low values of these characteristics indicating rathe r high flexibility of the chain are discussed. (C) 2000 Elsevier Science Lt d. All rights reserved.