A review on the relaxation dynamics analysis of unentangled polymers with different structures.

Relaxation dynamics of unentangled polymer melts (with a chain length below N = 100 for polyethylene) can be studied by performing either Rouse mode or relaxation mode analysis, such as proper orthogonal decomposition. The former mode analysis can be derived analytically from the linear equation of motion of polymers with the inclusion of inertia term, whereas the latter is designed for the case when the numerical solution to a highly nonlinear equation of motion is known, such as MD simulation data. This article presents a summary of both approaches and their applications in the evaluation of zero-shear viscosity of polymer melts. [ABSTRACT FROM AUTHOR]