Li Xiao-jing, Qiao Guan-jun, Chen Jie-rong
State Key Laboratory of Mechanical Behavior of Materials, Xi' an Jiaotong University, Xi' an 710049, China.
Huan Jing Ke Xue. 2007 May;28(5):963-8.
Effects of plasma-initiated free radicals on photocatalytic degradation of medical PVC with anatase TiO2 were studied. Surface properties of PVC were characterized by the contact angle, surface tension, X-ray photoelectron spectroscopy (XPS) and electron spin resonance (ESR). The results indicate that the surface free energy and wettability of plasma-treated PVC increase greatly. The contact angles of distilled water, glycerin and dihydroxyethylsulfide for the plasma-treated PVC decrease. ESR reveals radicals on the surface of the plasma-treated PVC film nearly increase ten times. Moreover, the photodegradation of the PVC-TiO2 was compared with that of plasma-treated PVC-TiO2 through performing weight loss monitoring, scanning electron microscopic (SEM) analysis. Weight-loss rate of the plasma-treated PVC-TiO2 increases 27.4% in comparison with that of PVC-TiO2 under UV irradiation for 60 hours. SEM of the plasma-treated PVC-TiO2 film shows a lot of crack on the surface after photodegradation. Plasma treatments aggravate the photocatalytic degradation of medical PVC.
研究了等离子体引发的自由基对锐钛矿型TiO₂光催化降解医用PVC的影响。通过接触角、表面张力、X射线光电子能谱（XPS）和电子自旋共振（ESR）对PVC的表面性质进行了表征。结果表明，经等离子体处理的PVC的表面自由能和润湿性大大增加。经等离子体处理的PVC对蒸馏水、甘油和二羟基乙硫醚的接触角减小。ESR显示，经等离子体处理的PVC薄膜表面的自由基数量几乎增加了10倍。此外，通过进行失重监测、扫描电子显微镜（SEM）分析，比较了PVC-TiO₂与经等离子体处理的PVC-TiO₂的光降解情况。在紫外光照射60小时后，经等离子体处理的PVC-TiO₂的失重率比PVC-TiO₂提高了27.4%。经等离子体处理的PVC-TiO₂薄膜的SEM显示，光降解后表面出现许多裂纹。等离子体处理加剧了医用PVC的光催化降解。
