膨胀阻燃聚乙烯的研究

Study on Intumescent Flame Retarded Polyethylene

将可膨胀石墨(EG)和传统的膨胀阻燃剂(IFR)用于制备膨胀阻燃聚乙烯(PE),采用极限氧指数对其阻燃性能进行了研究,探讨了2种阻燃剂之间的协同阻燃作用,并采用差示扫描量热仪和红外光谱对其热降解过程和炭层结构分别进行了分析。结果表明,EG和IFR对PE具有很好的协同阻燃作用,当其配比为1∶1时,膨胀阻燃PE可获得较佳的阻燃性能,阻燃剂用量仅为30份就可使膨胀阻燃PE的极限氧指数达到31.5%,远高于单一阻燃体系;在热降解过程中,复合膨胀阻燃体系仍表现出EG和IFR的特征降解过程,热降解成炭由二者的热降解产物构成,证实了二者之间的物理作用机理,物理膨胀炭层和化学膨胀炭层的结合有效增加了炭层的隔热、隔氧作用,有利于阻燃性能的改善。

Expandable graphite （EG） and traditional intumescent flame retardants （IFR） were introduced into polyethylene （PE）. The flame retardancy of the system was studied using differential scanning calorimetery （DSC）, Fourier transform infrared spectroscopy （FTIR） and testing of limited oxygen index. A strong synergistic effect between EG and IFR was observed. As a result, a limited oxygen index value of 31.5 ~ was achieved by adding 30 phr EG/IFR in PE, which was much higher than that of PE/EG or PE/IFR. The physical interaction between EG and IFR during thermal degradation was proved by their individual degradation behavior and char structure of the composite. The char formed by thermal degradation of EG and IFR was integrated to form an efficient barrier to oxygen and heat, which was in favor of the flame retardancy.