Predictive relation for the -relaxation time of a coarse-grained polymer melt under steady shear
Jack F. Douglas, Andrea Giuntoli, Francesco Puosi, Dino Leporini, Francis W. Starr
We examine the influence of steady shear on structural relaxation in a model coarse-grained unentagled polymer melt over a wide range of temperature and shear rates. Shear is found to progressively suppress the α-relaxation process observed in the intermediate scattering function, leading ultimately to a purely inertially dominated β-relaxation at high shear rates. The observed trend upon increasing shear is qualitatively similar to increasing temperature, which likewise diminishes the contribution of the α-relaxation to structural relaxation. Parallel trends with increasing shear rate and temperature are also reflected in the variation of the stretching exponent describing structural relaxation.
polymer melt, relaxation time, intermediate scattering function, shear thinning, beta relaxation, alpha relaxation, suppression of alpha relaxation by shear