Dynamics of Long Entangled Polyisoprene Melts via Multiscale Modeling

Abstract

A recently proposed hierarchical triple-scale simulation methodology (Behbahani et al., Macromolecules, 2021,54, 2740–2762) is applied to cis-1,4 polyisoprene melts of a broad range of molecular weights, from oligomers to commercial-grade entangled materials. Dynamics are systematically probed over 12 orders of magnitude in time using a combination of atomistic and bottom-up parameterized coarse-grained and slip-spring simulations. Following calibration of the slip-spring simulations using the end-to-end autocorrelation function, generated data are contrasted to dielectric relaxation spectroscopy experiments and rheological measurements in the literature. A good agreement is found, particularly for highly entangled polymer melts, supporting the ability of the scheme to provide bottom-up parameter-free predictions on the dynamics of polymeric materials. Finally, we systematically examine the application of theoretical models to our strictly monodisperse cis-1,4 polyisoprene melts and provide estimates of the phenomenological parameters employed.