DETERMINATION OF THE ELASTIC COMPONENT FOR POLYMERIC MELT UNDER STEADY SHEAR-FLOW

Steady state shear flow in rectilinear coordinates can be generated by a direct shear rheometer. The rheological behavior of polymeric melts under shear flow can be characterized by the inception of steady shea r flow and stress relaxation after cessation of steady shear flow. Exp eriments were performed for bisphenol A polycarbonate with various mol wts. The elastic components, such as the primary normal stress differ ences and the elastic recoverable shear strain of the polymeric melts, can be determined from the shear moduli.