Stability of the PBLG helix at high temperature and the wormlike character of the helix

Abstract

Viscosity and electric birefringence of poly(γ-benzyl-L-glutamate) (PBLG) in m-cresol have been measured up to 200°C (viscosity) and up to 170°C (electric birefringence), respectively. Dipole moments, optical anisotropy factors, mean relaxation times of birefringence, and intrinsic viscosities of PBLG at various temperatures have been determined. No abrupt changes which suggest breakage of the helix structure have been observed on hydrodynamical and electrooptical properties. However, the PBLG helix becomes considerably more flexible with increasing temperature. Persistence lengths of PBLG helix at various temperatures have been estimated from dipole moments, relaxation times, and intrinsic viscosity data. © 1973, The Society of Polymer Science, Japan. All rights reserved.