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arXiv · cond-mat/0606008

Density and conformation with relaxed substrate, bulk, and interface electrophoretic deposition of polymer chains

Abstract

Characteristics of relaxed density profile and conformation of polymer chains are studied by a Monte Carlo simulation on a discrete lattice in three dimensions using different segmental (kink-jump $K$, crank-shaft $C$, reptation $R$) dynamics. Three distinct density regimes, substrate, bulk, and interface, are identified. With the $KC$ segmental dynamics we find that the substrate coverage grows with a power-law, $d_s \propto t^γ$ with a field dependent nonuniversal exponent $γ= 0.23 + 0.7 E$. The bulk volume fraction $d_b$ and the substrate polymer density ($d_s$) increases exponentially with the field ($d_b \propto E^{0.4}$, $d_s \propto E^{0.2}$) in the low field regime. The interface polymer density $d_f$ increases with the molecular weight. With the $KCR$ segmental dynamics, bulk and substrate density decreases linearly with the temperature at high temperatures. The bulk volume fraction is found to decay with the molecular weight, $d_b \propto L_c^{-0.11}$. The radius of gyration remains Gaussian in all density regions.

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Frank W. Bentrem, Jun Xie, R. B. Pandey. 2006-06-13. Density and conformation with relaxed substrate, bulk, and interface electrophoretic deposition of polymer chains. https://doi.org/10.1016/s0166-1280(02)00230-0

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