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Investigation of Dynamical Heterogeneities in Polymer Melts


Affiliations
1 Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247 667, India
 

In this paper, dynamical heterogeneities are characterized both at the monomer and centre-of-mass level, in polymer melts well above their glass transition temperature, responsible for anomalous dynamics in these systems. Microscopic analysis of united atom molecular dynamics simulations of unentangled polyethylene melts suggests a molecular mechanism for the observed heterogeneous dynamics based on local density fluctuations about a tagged polymer. These local density fluctuations are related to variations in entropy in a small volume about a polymer in the melt, which result in initial connections of the dynamical heterogeneities to entropy.

Keywords

Dynamics, Heterogeneities, Microscopic Analysis, Polymer Melts.
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  • Investigation of Dynamical Heterogeneities in Polymer Melts

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Authors

Rupam Borah
Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247 667, India
Nabi Ahamad
Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247 667, India
Pallavi Debnath
Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247 667, India

Abstract


In this paper, dynamical heterogeneities are characterized both at the monomer and centre-of-mass level, in polymer melts well above their glass transition temperature, responsible for anomalous dynamics in these systems. Microscopic analysis of united atom molecular dynamics simulations of unentangled polyethylene melts suggests a molecular mechanism for the observed heterogeneous dynamics based on local density fluctuations about a tagged polymer. These local density fluctuations are related to variations in entropy in a small volume about a polymer in the melt, which result in initial connections of the dynamical heterogeneities to entropy.

Keywords


Dynamics, Heterogeneities, Microscopic Analysis, Polymer Melts.

References





DOI: https://doi.org/10.18520/cs%2Fv113%2Fi10%2F1974-1985