不同光源条件下PVC涂层膜材料的光氧老化性能

Photo-Oxidation of PVC-Coated Membrane Material under Different Light Sources

以聚氯乙烯(PVC)涂层膜材料为研究对象,分别采用UVB313和UVA340型紫外灯管为光源进行人工加速老化试验,研究其光氧老化过程.对老化过程中试样的拉伸性能进行测试,并进行红外光谱和紫外光谱分析,以探究其光氧老化动力学过程.试验结果表明:两种光源条件下试样的光氧老化机制没有发生变化,但当累积紫外辐射能相同时,试样的老化程度并不一致,这是由两种光源的发光光谱不同造成的,因此,互易定律不适用于PVC涂层膜材料寿命预测模型的建立.根据两光源发光光谱的不同,引入有效紫外辐射的概念,依据改进的Schwarzschild定律建立了不同光源条件下PVC涂层膜材料老化结果的相关性.

Photo-oxidation process of polyvinylchloride-coated （PVC-coated）membrane material was studied by artificial accelerated aging tests using UVB313 lamp and UVA340 lamp as light sources respectively. Tensile strengths of the samples were tested during the experiment, FTIR （Fourier transform infrared spectroscopy） technique and UV-Vis （ultra-violet-visible spectroscopy）technique were used to analyze the photo-oxidation reaction dynamic processes of aging samples. It was found that photo-oxidation mechanism of the samples didn＇t change under different light sources, but the aging degree of the samples was not equivalent under the same cumulative UV radiation energy. The different aging degree of the samples is related to the difference of the two lamps＇ spectrum. Therefore, reciprocity law is not suitable for the building of PVC＇s life prediction model in this experiment. According to the difference of two lamps＇ spectrum, effective UV radiation is introduced in the improved Schwarzschild＇s law, and the correlation of PVC-coated membrane material＇s aging results under different light sources is established.