以锐钛型二氧化钛作为催化剂在紫外光下催化降解聚乙烯醇（PVA）溶液。通过化学需氧量除去率和相对黏度测定,探讨了不同初始浓度PVA溶液紫外光催化降解的规律：随紫外光辐照时间延长,PVA溶液化学需氧量除去率增加;PVA溶液相对黏度呈先下降后上升再下降趋势;较低初始质量浓度（0.4 g/L）PVA溶液比较高初始质量浓度（1 g/L）PVA溶液更容易降解。通过紫外-可见吸收光谱和红外吸收光谱分析,研究了PVA经紫外光降解后的结构变化,结果表明,降解伊始,PVA分子链被破坏,有碳碳双键和羰基形成,而进一步降解后碳碳双键消失。
Photo-catalytic degradation of poly（vinyl alcohol）（PVA） aqueous solution under UV light was carried out using nano-titanium dioxide（TiO2,anatase） as photocatalyst and monitored by the determination of the chemical oxygen demand（COD） and viscometry.The experimental results show that,with the UV irradiation,the removal of COD for PVA solution with 0.4 g/L initial concentration increases but that for PVA solution with initial concentration higher than 0.4 g/L hardly has change,while the relative viscosities of PVA solutions with different initial concentration decrease firstly then increase and finally decrease again.Structures of PVA after UV irradiation were characterized by ultraviolet-visible spectrophotometer and Fourier transform infared spectroscopy.The result illuminates that carbon-carbon double bonds（C=C） and carboxyl（C=O） bonds form when PVA chains begin to degrade,and with further degradation,C=C bonds disappears.
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