THE BEHAVIOR OF GRAFTED POLYMERS IN RESTRICTED GEOMETRIES UNDER POOR SOLVENT CONDITIONS

We determine the behavior of chains that are grafted in restricted geo metries, such as a planar stripe of finite width and around a circular pore. Immersed in a poor solvent, the chains associate into a variety of complexes. By calculating the free energy of these complexes, we d etermine how their sizes scale with chain length, solvent quality, gra fting density, and the dimensions of the substrate. We also construct a ''phase diagram'' for the possible morphologies that can occur in th ese systems. In the case of circular pores, we use Monte Carlo simulat ions to visualize the structure of the associated complexes. The resul ts reveal how edge effects can be exploited to design polymer layers t hat provide protective coatings or regulate the flow of molecules thro ugh tile substrate. (C) 1996 American Institute of Physics.