SURFACE MODIFICATION OF MEDICAL POLYURETHANE BY SILICON ION-BOMBARDMENT

The biocompatibility of Si+-implanted medical polyurethane was studied. Si ion implantation was performed at energies of 40, 60, 80, and 100 keV with doses ranging from 2x 1013 to 2x 1016 CM-2 at room temperature. The results show that the wettability, blood adsorption, anticoagulability and anticalcific bahaviours of the surface were changed significantly by ion bombardment. The results of SEM and XPS analyses indicate that some of the original chemical bonds in the surface region were broken and the degree of destruction was increased after implantation, which was probably the main reason for the surface modification. ESR shows that the number of radicals is not beyond the range 10(12) to 10(14) cm-3, which is advantageous for the clinical utilization of polyurethane.