Blood compatibility of poly(ethylene oxide)-grafted polyurethane/ polystyrene IPN

Abstract

PEO-grafted PU/PS IPNs were synthesized, and the blood-compatibility was investigated considering the effect of the mobile PEO side chains and their microphase separated structure. PEO-grafted PU homopolymers were also synthesized to observe the effect of only the PEO side chain, excluding the effect of microphase separated structure. The morphology of the fracture surfaces indicates that the size of dispersed domains of PS-rich phase decreased as the content of side chains increased, because the phase separation was more restricted due to the increase of the viscosity of the casting mixture. PU/PS IPNs have an excellent mechanical property compared with PU homopolymers. Swelling ratio decreased as the grafting with PEO was increased, however the dynamic contact angle and interfacial energy between surface and water decreased at the hydrated state, due to the structural reorganization of the pendant PEO chains. In the blood compatibility test, the amount of platelets adsorbed, activated and coagulated upon the PEO-grafted PU/PS IPNs were reduced when compared to the ungrafted PU homopolymers.