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DOE OSTI · 1482733

Polymers at Liquid/Vapor Interface

Peters, Brandon L.·Pike, Darin Q.·Rubinstein, Michael·Grest, Gary S.
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Abstract

Polymers confined to the liquid/vapor interface are studied using molecular dynamics simulations. We show that for polymers which are weakly immiscible with the solvent, the density profile perpendicular to the liquid/vapor interface is strongly asymmetric. On the vapor side of the interface, the density distribution falls off as a Gaussian with a decay length on the order of the bead diameter, whereas on the liquid side, the density profile decays as a simple exponential. This result differs from that of a polymer absorbed from a good solvent with the density profile decaying as a power law. In conclusion, as the surface coverage increases, the average end-to-end distance and chain mobility systematically decreases toward that of the homopolymer melt.

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Peters, Brandon L., Pike, Darin Q., Rubinstein, Michael, Grest, Gary S.. 2017-10-11. Polymers at Liquid/Vapor Interface. https://doi.org/10.1021/acsmacrolett.7b00466

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