Department of Physics, DSB Campus, Kumaun University, Naini Tal-263 002, Uttarakhand, India.
J Phys Condens Matter. 2010 Apr 21;22(15):155103. doi: 10.1088/0953-8984/22/15/155103. Epub 2010 Mar 9.
A lattice model of a directed self-avoiding walk is used to investigate adsorption properties of a semiflexible alternating copolymer chain on an impenetrable flat and fluctuating surface in two (square, hexagonal and rectangular lattice) and three dimensions (cubic lattice). In the cubic lattice case the surface is two-dimensional impenetrable flat and in two dimensions the surface is a fluctuating impenetrable line (hexagonal lattice) and also flat impenetrable line (square and rectangular lattice). Walks of the copolymer chains are directed perpendicular to the plane of the surface and at a suitable value of monomer surface attraction, the copolymer chain gets adsorbed on the surface. To calculate the exact value of the monomer surface attraction, the directed walk model has been solved analytically using the generating function method to discuss results when one type of monomer of the copolymer chain has attractive, repulsive or no interaction with the surface. Results obtained in the flat surface case show that, for a stiffer copolymer chain, adsorption transition occurs at a smaller value of monomer surface attraction than a flexible copolymer chain while in the case of a fluctuating surface, the adsorption transition point is independent of bending energy of the copolymer chain. These features are similar to that of a semiflexible homopolymer chain adsorption.
使用有向自回避行走的格点模型研究了在不可穿透的平面和二维（正方形、六边形和矩形格点）和三维（立方格点）中半刚性交替共聚物链在不可穿透的平面和波动表面上的吸附性质。在立方格点情况下，表面是二维不可穿透的平面，而在二维情况下，表面是波动的不可穿透线（六边形格点）和不可穿透的平面线（正方形和矩形格点）。共聚物链的行走垂直于表面的平面，在单体表面吸引力的适当值下，共聚物链被吸附在表面上。为了计算单体表面吸引力的精确值，使用生成函数方法对定向行走模型进行了解析求解，以讨论共聚物链的一种单体与表面具有吸引力、排斥力或无相互作用的情况。在平面表面的情况下得到的结果表明，对于刚性较大的共聚物链，吸附转变发生在单体表面吸引力较小的情况下，而对于波动表面，吸附转变点与共聚物链的弯曲能无关。这些特征与半刚性均聚物链的吸附相似。
