On the interchain associations in aqueous solutions of a succinoglycan polysaccharide

Formation of interchain associations between succinoglycan chains have been studied by comparing weight average molecular weight, intrinsic viscosity of succinoglycan as a function of the conditions to prepare the solutions (polymer concentration, the heating temperature adopted compared with T_m). The different solutions obtained were characterized by their Newtonian viscosity, the storage and loss moduli and their sensitivity to the temperature. It was found that interchain associations, first stabilized mainly during the disorder-order transition convert to more stable associations by aging at temperatures below but not too far from T_m. These associations appear from succinoglycan solutions characterized by an overlap parameter higher than about 8 and modify only very slightly the conformational transition parameters obtained from microcalorimetry measurements.