Abstract
Double polymer networks (DNs) with poly(N-(3-sulfopropyl)-N-methacroyloxyethyl-N, N- dimethylammonium betaine) component as a high density cross-linking agent were synthesized by thermoinitiated cross-linking polymerization. Good mechanical properties of the produced DNs were established. These, in combination with an excellent biocompatibility of polyzwitterions, open a possibility for wide biomedical applications of these materials. It is also shown that the mechanical properties could be controlled by the factors (cross-linking agent and monomer concentrations, temperature and time for the cross-linking polymerization, order of single network formation) influencing the junction point densities of the two single networks and on the microphase separation taking place during the formation of the second single network. Specific dipole-dipole interaction between polyzwitterion monomer units as a reason for this separation is a distinct peculiarity of poly(N-(3-sulfopropyl)-N-methacroyloxyethyl- N,N-dimethylammoniumbetaine)/ poly( acrylamide) double networks in comparison to poly(2-acrylamido-2-methylpropanesulfonic- acid)/ poly( acrylamide) ones.