Medical Titanium Surface Of The Plasma Modified

Comparing with other traditional medical metal materials, the titanium is one kind of materials used widely in medicine field because of its premium properties of light mass, high strength, fatigue resistance and good biocompatibility. But the titanium has many insurmountable defects, for example, the titanium can be eroded in physical environment, so the harmful metal ion will diffuse in the body, there maybe has the phenomenon of sensitivity, sudden change, carcinogenesis, and so on. Therefore, the research development on both fully displaying the titanium performance, and entrusting with its biomaterial become one of current domestic and foreign research hot spots. The main work is shown as follows:(1) For improving corrosion resistance and biocompatibility of pure titanium, polyacrylamide (PAAm) molecules were grafted on pure titanium surface by plasma pretreatment, self-assembled 3-mercaptopropyl trimethoxysilane (MPS) and plasma-initiated polymerization. Effects of plasma treated parameters, MPS concentration and AAm monomer concentration on graft degree were investigated. By means of attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), contact angle (CA), energy dispersive spectroscopy (EDS), atomic force microscopy (AFM) and gel permeation chromatography (GPC), it was indicated that a MPS membrane formed on the titanium substrate by plasma pretreatment, and the acrylamide monomer initiated by plasma can been graft-polymerized with the mercapto groups of MPS membrane on the titanium surface.(2) For improving biocompatibility of pure titanium, the titanium was pretreated by O₂ plasma, then was dipped in the chitosan solution, and was subject to chemically link with chitosan. Effects of chitosan's concentration, plasma treatment power, time and Ar pressure were investigated. The surface components and microstructure were studied by X-ray photoelectron spectroscope (XPS), CA, ATR-FTIR and scanning electron microscopy (SEM). Results of cytotoxicity test showed that cell biocompatibility of the modified titanium surface was improved clearly.(3) For improving corrosion resistance of the titanium, CF₄ plasma was used to prepare fluorinated amorphous carbon films (a-F:C) by plasma chemistry vapor deposition on the titanium surface. By means of ATR-FTIR, it was indicated that the C=C groups formed on Ti surface when the plasma power was 130 W. By SEM it was seen that the film had a three-dimensional reseau when the plasma power was 50 W. Results of corrosion test showed that depositting fluorinated amorphous carbon films on pure titanium surface could improve corrosion resistance of the titanium.