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Effect of Equilibration on Primitive Path Analyses of Entangled Polymers

Robert S. Hoy·Mark O. Robbins
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Abstract

We use recently developed primitive path analysis (PPA) methods to study the effect of equilibration on entanglement density in model polymeric systems. Values of N_e for two commonly used equilibration methods differ by a factor of two or three even though the methods produce similar large-scale chain statistics. We find that local chain stretching in poorly equilibrated samples increases entanglement density. The evolution of N_e with time shows that many entanglements are lost through fast processes such as chain retraction as the local stretching relaxes. Quenching a melt state into a glass has little effect on N_e. Equilibration-dependent differences in short-scale structure affect the craze extension ratio much less than expected from the differences in PPA values of N_e.

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Robert S. Hoy, Mark O. Robbins. 2005-10-23. Effect of Equilibration on Primitive Path Analyses of Entangled Polymers. https://doi.org/10.1103/physreve.72.061802

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