Effect of matrix polymer on flow-induced nucleation in polymer blends.

Long-chain molecules in polymers are responsible for flow-induced nucleation (FIN). The role of a short-chain matrix in FIN was investigated using bidisperse blends of polyethylenelike high molecular weight long chains in short-chain polymer matrices. It was found that the critical specific work, w(c), measured for the onset of FIN in the blends has a power law dependence on the molecular weight of the matrix polymer with w(c) proportional M(w)(2.59 ± 0.27) indicating that the matrix can affect the stretching of the long chains and limit their ability to act as nucleation sites for flow-induced crystallization.