RELAXATION-TIME DISTRIBUTIONS OF ENTANGLED POLYMER-SOLUTIONS FROM DYNAMIC LIGHT-SCATTERING AND DYNAMIC MECHANICAL MEASUREMENTS

Recent Laplace inversion analyses of dynamic lightscattering (DLS) data on semidilute solutions of high molecular weight polystyrene (PS) at the temperature established the existence of a distribution of slower relaxation times, which was independent of the wave vector(q) of the incident light, in addition to the fast q2-dependent relaxation time which describes the cooperative diffusion of the polymer chains.1“4 Although the contribution of the slower relaxational modes to the correlation function persists at temperatures well above the temperature and is even detectable in thermodynamically good solvents, their relative amplitude is only considerable (dominant) at temperatures in the vicinity of θ. © 1990, American Chemical Society. All rights reserved.