Final Activity Report Summary - GRADIENT COMPOSITES (Novel multicomponent polymer systems with compositional gradient for biomedical application)
The studies were performed on two series of the gradient semi-interpenetrating polymer networks with varied composition at different depths from the surface, which consist of the polyurethane elastomer and biocompatible hydrophilic polymers polyvinylpyrrolidone and poly(hydroxyethyl methacrylate). The thermodynamic miscibility, phase distribution, morphology, dynamic mechanical properties, dielectric properties, bacterial adhesion and cytotoxicity of semi-interpenetrating polymer networks and gradient polymer composites have been investigated.
It was shown that biocompatibility of polymer materials can be substantially improved playing on the nanoscale morphology created by hydrophilic polymers in the surface layers of matrix polymer. The altering of nanostructure at the surface of polymer composites allow to reduce the bacterial adhesion. The creation of the gradient semi-IPNs based on polyurethane and poly(hydroxyethyl methacrylate), polyurethane and polyvinylpyrrolidone allow to save the mechanical properties of samples in hydrated state on the tolerable level for using them in bioengineering purpose. Taking into account that the semi-IPNs and gradient composites with poly(hydroxyethyl methacrylate) content above 22 % are not toxic, the results suggest that the composites may have optimised characteristics as advanced biomaterials.