The linear viscoelastic properties of linear polymers melts and solutions are well understood and can be quantitatively described by models such as the tube model. On the contrary, the nonlinear charactersitics of polymers (like in fast extensional flow) is not well understood principally due to the non-universal behavior between polymer melts and solutions. Currently, there is no single model in literature that can describe both polymer melts and solutions together under one framework. So the primary objective of this thesis is to develop an universal model that could correctly predict the fast extensional behavior of monodisperse linear polymers.