燃气用聚乙烯管材的人工气候加速老化

以氙灯作为辐照光源,对外径分别为110 mm和63 mm的两种规格聚乙烯燃气管进行了人工气候加速老化试验,通过测试聚乙烯燃气管试样在不同累积接受能量下的氧化诱导时间、拉伸性能、熔体流动速率(MFR)等3项重要性能指标的变化,探讨人工气候加速老化对聚乙烯燃气管物理力学性能的影响规律。结果表明,在接受能量为3.5 GJ/m2时,聚乙烯燃气管试样表面发生严重老化,其氧化诱导时间均小于10 min;当接受能量达到4 GJ/m2时,试样氧化诱导时间急剧衰减,均小于5 min,其表面几乎完全老化。随着接受能量的增加,所有试样的拉伸屈服强度和断裂伸长率的变化幅度均较小,与无色条试样相比,表面带有黄色色条试样的断裂伸长率发生锐减,所有试样的MFR未发生较大变化。

Accelerated Aging of Polyethylene Gas Pipe under Artificial Climate

Using xenon lamp as irradiation light source,the accelerated aging tests under artificial climate of two specifications polyethylene gas pipe with 110 mm and 63 mm were done. Through studying the changes of three important performance indexes (oxidation induction time,tensile property and melt flow rate) of polyethylene gas pipe samples under different irradiation energy, the influence law of the accelerated aging under artificial climate on the physical and mechanical properties of polyethylene gas pipe was investigated. The results show that,after receiving the energy of 3.5 GJ/m2,the surface aging of all samples are very serious and the oxidation induction times are less than 10 min,after receiving the energy of 4 GJ/m2,the oxidation induction times are declined sharply and less than 5 min,the surfaces of all samples are aged almost entirely. With the increase of the energy,the tensile yield strength and elongation at break of all samples are changed little,however,compared with samples without color bars,the elongation at break of samples with yellow bars on surface are dropped markedly,the melt flow rate of all samples remain almost un-changed.