Title

Isostaticity and the Solidification of Semiflexible Polymer Melts

Document Type

Article

Publication Date

2017

Digital Object Identifier (DOI)

https://doi.org/10.1039/C7SM01442B

Abstract

Using molecular dynamics simulations of a tangent-soft-sphere bead-spring polymer model, we examine the degree to which semiflexible polymer melts solidify at isostaticity. Flexible and stiff chains crystallize when they are isostatic as defined by appropriate degree-of-freedom-counting arguments. Semiflexible chains also solidify when isostatic if a generalized isostaticity criterion that accounts for the slow freezing out of configurational freedom as chain stiffness increases is employed. The configurational freedom associated with bond angles (θ) can be associated with the characteristic ratio C∞ = (1 + 〈cos(θ)〉)/(1 − 〈cos(θ)〉). We find that the dependence of the average coordination number at solidification [Z(Ts)] on chains' characteristic ratio C∞ has the same functional form [Zab ln(C∞)] as the dependence of the average coordination number at jamming [Z(ϕJ)] on C∞ in athermal systems, suggesting that jamming-related phenomena play a significant role in thermal polymer solidification.

Was this content written or created while at USF?

Yes

Citation / Publisher Attribution

Soft Matter, 13, p. 7948-7952

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