Surface Modification of Medical Polyurethane by Plasma Treatment

The wettability and surface structure of plasma treatment on medical polyurethane were studied. Two kinds of gas, N₂, Ar, were used to create the low-temperature plasma under low pressure. The wettability was investigated by means of the sessile drop method using water, the results show that the contact angle of water decreases from 78.8^o to 61.9^o as the treatment time increases. The results of electron spectroscopy for chemical analysis indicate that original chemical bonds were broken up after plasma treatment, which was the main reason for the surface modification. At same time, the results of electron spinning resonance show that the amounts of radicals did riot increase significantly after treatment, which is advantageous to clinical practice of polyurethane.