Interface relaxation in electrophoretic deposition of polymer chains: effects of segmental dynamics, molecular...

Using different segmental dynamics and relaxation, characteristics of the interface growth is examined in an electrophoretic deposition of polymer chains on a three (2+1)-dimensional discrete lattice with a Monte Carlo simulation. Incorporation of faster modes such as crankshaft and reptation movements along with the relatively slow kink-jump dynamics seems crucial in relaxing the interface width. As the continuously released polymer chains are driven (via segmental movements) and deposited, the interface width W grows with the number of time steps t, W proportional, variant t(beta), (beta approximately 0.4-0.8), which is followed by its saturation to a steady-state value W(s). Stopping the release of additional chains after saturation while continuing the segmental movements relaxes the saturated width to an equilibrium value (W(s)-->W(r)). Scaling of the relaxed interface width W(r) with the driving field E, W(r) proportional, variant E(-1/2) remains similar to that of the steady-state W(s) width. In contrast to monotonic increase of the steady-state width W(s), the relaxed interface width W(r) is found to decay (possibly as a stretched exponential) with the molecular weight.