Density Functional Model of Anchoring Energy at a Liquid Crystalline Polymer - Solid Interface

(Received 30 November 1993, revised 5 July 1994, accepted 28 September 1994)

Abstract
A statistical mechanical expression for the anisotropic surface (anchoring) energy of a nematic polymer melt is derived in the molecular field approximation using the density functional approach. It is shown that this energy can be very large,  erg/cm ². It is shown that a crossover exists between the two characteristic scaling regimes of W. At low nematic order parameter S the anchoring energy is determined by the change in the single chain entropy due to the steric restriction near the wall and is proportional to the large longitudinal persistence length l_|| of the folded chain. In highly ordered system ( S>0.55) W is dominated by pair interactions between the chain segments, modulated by the steric effect of the wall, and is proportional to the higher power, l_||^7/4.