FeSt_3对煤基聚乙烯薄膜光-热降解性能的影响

The Influence of FeSt_3 Content on Photo-Thermal Degradation Property of Polyethylene Film

通过拉伸强度和断裂伸长率、TG以及FTIR的测试分析,研究硬脂酸铁(FeSt3)含量不同的4种煤基聚乙烯薄膜在模拟自然光条件下的光-热降解性能。结果表明:光照时薄膜中添加的煤粉在FeSt3作用下发生自由基反应,引发聚乙烯大分子断链,产生羰基;羰基指数随薄膜中FeSt3含量的增加而增大,但薄膜力学性能相应降低,热稳定性则有所增强;聚乙烯大分子链结构在光照作用下发生脱羰基反应,断裂成小分子链;降解薄膜在光照72小时前处于衰变期,72小时后进入脆变期。

Photo-thermal degradation property of polyethylene films with different FeSt3 content was studied after irradiation by stimulated sunlight. Tensile strength, elongation at break, TG and FTIR of the films were analyzed. The results showed that FeSt3 with coal added in films could produce radical reaction and induce big molecular chains of polyethylene to break and form carbonyl group during irradiation. The earbonyl index was increasing, but mechanical property was decreased and thermal stability was enhanced with the increasing of FeSt3 content in films. The chains structure of polymer could break into lower molecular matter by reaction of extracting carbonyl by irradiation. The films were in embrittlement stage before 72 h irradiation and in ageing stage after 72 h irradiation.