EFFECT OF H-BONDING INTERACTIONS ON THE COLLECTIVE BEHAVIOR OF POLYMER-CHAINS ANCHORED TO A FLAT SURFACE

By combining statistical and quantum mechanical calculations, we have developed an approximate but simple method to investigate the effect of H-bonding on the mean height of a system formed by interacting polymer chains anchored to a flat surface (polymer brushes). In particular, we have investigated polymers lying in two dichotomic conformational states, one forming internal H-bonds and the other showing preferential interactions with solvent or adjacent chains. The model has been applied to polysaccharide chains attached to a flat surface selected as a model of a cell membrane surface. The solution of the statistical problem has been approached by a recent self-consistent field (SCF) analytically solvable method, while the evaluation of molecular parameters (e.g. energies of inter- and intramolecular conformations) needed to obtain numerical estimates has been derived by quantum mechanical and solvation energy (continuum approximation) calculations. Four structurally similar saccharides (alpha-glucose, beta-glucose, alpha-galactose and beta-galactose) were investigated. The results suggest noticeable differences of brush height among the studied molecules, further evidencing how small variations of H-bond energy and molecular conformation may lead to dramatic changes in the collective behaviour of complex systems.