Secondary relaxation processes in bisphenol-A polysulphone

  title={Secondary relaxation processes in bisphenol-A polysulphone},
  author={Joel R. Fried and Alan Letton and W. J. Welsh},
Abstract Dynamic mechanical spectra of bisphenol-A polysulphone in torsional deformation have been obtained as a function of frequency and thermal history. Results indicate a major low-temperature γ peak at 166 K and a broad, low-intensity β peak near 352 K at 10 rad s −1 for quenched samples. Activation energies have been estimated to be 10.7 and 67.3 kcal mol −1 , respectively. Annealing eliminates the β peak and intensifies the shoulder of the γ peak. Geometry-optimized CNDO/2 (complete… CONTINUE READING