Critical adsorption of a flexible polymer on a stripe-patterned surface

Abstract

The adsorption and dynamics of a polymer chain on a stripe-patterned surface composed of periodical attractive and neutral stripes are studied by using Monte Carlo simulation. The critical adsorption temperature T_c and pattern-recognition temperature T_r are estimated from the desorption probability, surface contact number, and bridge number. A phase diagram presenting three polymer states, including a desorbed state above T_c, a multi-stripe adsorbed state at an intermediate temperature T_r < T < T_c, and a single-stripe adsorbed state below T_r, is provided for infinitely long chains. Normal diffusion is always observed for a polymer in the direction parallel to the stripe even at low temperature. But in the direction perpendicular to the stripe, the polymer can freely diffuse above T_c, whereas the polymer is confined to one attractive stripe below T_r. However, the adsorbed polymer can hop from one attractive stripe to another at the intermediate temperature T_r < T < T_c.