CORRELATION BETWEEN CHEMICAL AND PHYSICAL SURFACE-PROPERTIES AND BLOOD COMPATIBILITY OF PPE EVA-BLENDS/

The chemical and physical surface properties of a biomaterial are of h igh importance for the blood compatibility of an implant. Blends of po ly(propylene-co-ethylene) with various amounts of poly(ethylene-co-vin yl acetate) (PPE/EVA-blends) were examined because of the varying surf ace hydrophilicity. Surface characterizations were performed by means of X-ray Photoelectron Spectroscopy (XPS), Infrared Spectroscopy in At tenuated Totalreflexion Mode (IR-ATR) in relation to dynamic contact a ngle and zeta potential measurements. The examination of the blood com patibility of the polymer surfaces was carried out in vitro in a modif ied BOWRY blood chamber with native whole human blood. A balanced rati o of polar and dispersive surface free energy and a zeta potential of -4 mV are the conditions for a good blood compatibility of the investi gated PPE/EVA-blends.