When stainless steel is implanted in human bodies, the corrosion resistance and biocompatibility must be considered. In this study, first, a protective organic silicone film was coated on the surface of stainless steel by a plasma deposition technique with a precursor of hexamethyldisilazane (HMDSZ). Then, ultraviolet (UV) light-induced graft polymerization of N-isopropylacrylamide (NIPAAm) and acrylic acid (AAc) in different molar ratios were applied onto the organic silicone film in order to immobilize thermos-/pH-sensitive composite hydrogels on the surface. The thermo-/pH-sensitive composite hydrogels were tested at pH values of 4, 7.4 and 10 of a phosphate buffer saline (PBS) solution at a fixed temperature of 37 °C to observe the swelling ratio and drug delivery properties of caffeine which served as a drug delivery substance. According to the results of Fourier Transformation Infrared (FTIR) spectra and a potential polarization dynamic test, the silicone thin film formed by plasma deposition not only improved the adhesion ability between the substrate and hydrogels but also exhibited a high corrosion resistance. Furthermore, the composite hydrogels have an excellent release ratio of up to 90% of the absorbed amount after 8h at a pH of 10. In addition, the results of potential polarization dynamic tests showed that the corrosion resistance of stainless steel could be improved by the HMDSZ plasma deposition.

Plasma treatment is the most popular surface modification process of polymers. A small cold plasma zone treatment is an important modification technique in modern industry. In this study, the effect of gas flow direction on plasma treatment was investigated. In order to decrease the plasma zone area, we added a separate cylinder to surround the upper electrode. The separate cylinder is effective in limiting the plasma discharge area, and we could find a light and dark area in the vacuum chamber. After O 2 plasma treatment, the result shows that only PP nonwoven in the discharge area became hydrophilic, but the other position away from the plasma zone was not affected. The water adsorption of PP nonwoven increased from 34.8% to 537.4%. When the sample is further from the plasma zone, near the up stream of gas flow, the surface property is less hydrophilic. The water contact angle analysis of PS and glass shows the same results as those of PP nonwoven. But PET in plasma zone or dark zone (plasma zone: 75 to 31 , dark zone: 75 to 52 ) both show hydrophilic property. The wettability effect in the dark zone may be due to the UV-light irradiation in the process of plasma excitation.

Modulating the morphological structure evolution of copper-based materials was accomplished by varying anion species in electroplating solution. The correlation between the surface morphology and their electrochemical behavior was investigated.

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