Nonlinear rheological behavior of diphenylmethylvinyl silicone gum: an example of homogeneous shear

The present work shows, based on an effective particle-tracking velocimetric (PTV) method, that a commercial diphenylmethylvinyl silicone gum displays nonlinear rheological responses to startup shear and large amplitude oscillatory shear (LAOS) in a homogeneous manner, in contrast to monodisperse melts. Using an effective cone-partitioned plate (CPP) setup along with PTV, rheological characterizations of shear thinning in continuous shear and strain softening in LAOS are carried out reliably without the inherent experimental complication associated with edge fracture. Conversely, based on the CPP, the rheological effects of edge fracture are also illustrated for both startup shear and LAOS.