典型大气环境对低密度聚乙烯老化严酷度评价方法

Evaluation Method about Aging of Low Density Polyethylene in Typical Atmospheric Environment

为评价典型大气环境对低密度聚乙烯(PE–LD)材料的老化严酷度,选取我国武汉、漠河、拉萨、万宁地区进行PE–LD大气环境自然老化试验,对曝晒3个月、6个月、12个月、18个月后的PE–LD试样进行力学性能、黄色指数、光泽度与红外光谱测试与分析。结果表明,PE–LD试样表面的红外羰基峰强度随老化时间延长出现饱和极大值,各地区出现极大值的老化时间因环境因素不同而不同,可用红外羰基峰强度变化来评价环境对PE–LD的老化严酷度;各地区对PE–LD的老化严酷度从大到小依次是万宁、武汉、拉萨、漠河。

To establish an evaluation method about the aging of low density polyethylene（PE-LD） in typical atmospheric environment, the variations of mechanical property, yellowness index, glossiness properties and ATR-FTIR of PE-LD specimens after aging for 3,6, 12,18 months in wuhan, mohe, lhasa, wanning area＇ s atmospheric environment were investigated and analyzed. The results indicate that the intensity of carhonyl group infrared spectrogram of PE-LD specimens surface will increase to a maximum and not change obviously with the aging time go on. At test sites, the aging time point is different because of the different environmental factors, the intensity of carbonyl absorption band can be used to evaluate the aging of PE-LD in atmospheric environment. From most to least, the aging severity of PE-LD is wanning, wuhan, lhasa and mohe.