Creep and recovery of anionic and technical polystyrenes

Abstract

The torsional creep and recoverable bahaviour is presented for a technical and an anionic polystyrene over seven orders in magnitude from 10−8 to 10−1 Pa−1 and over more than seven decades in time. The results for the recoverable compliance J R (t) reveal a dispersion region between the glass transition and the steady-state recoverable compliance J e . The limiting value of the final dispersion J e = 4.7 · 10−4Pa−1 indicates a broad-MWD polystyrene, whilst the narrow-MWD anionic polystyrene shows only a slight step from the rubbery plateau to a value for J e of 1.12 · 10−5 Pa−1. In spite of this, the steady-state recoverable compliance J e is independent of temperature for both PS N 7000 and L 84. The temperature dependence of the final dispersion for both polystyrenes was found to be indistinguishable from that of viscous deformation. However, this temperature dependence differs significantly from that of the glass transition. A method has been suggested for constructing a “true” master curve at each arbitrary reference temperature.