Molecular orientation dependent dynamic viscoelasticity in uni-axially drawn polycarbonate

Abstract Molecular orientation and dynamic modulus of the high and low temperature drawn polycarbonate splines were investigated using wide-angle X-ray diffraction (WAXD) and dynamic mechanical analysis (DMA). For high-temperature stretched splines, the storage modulus in the glassy state and the loss modulus in the rubbery state increased with increasing the orientation. No obvious regularity was observed for the low-temperature stretched ones. These behaviors could be interpreted by a relation between relaxation modulus and average orientation angle, which was derived from the elastic dumbbell model and wormlike chain model. Through associating the molecular orientation defined by Herman's factor with the storage modulus at the end of the glassy state plateau and the loss modulus at the tan δ peak respectively, the relationship between orientation and dynamic viscoelasticity of polycarbonate was built as well.