Fe-Sr2Bi2O5光催化降解低密度聚乙烯膜

采用共沉淀法合成的新型光催化剂(Fe-Sr₂Bi₂O₅)与低密度聚乙烯(LDPE)通过熔融共混制备了一种新型光催化降解复合膜(Fe-Sr₂Bi₂O₅/PE)。通过力学性能、接触角、傅里叶变换红外光谱(FT-IR)和场发射扫描电镜(FESEM)等表征手段研究了该催化剂在室温条件下固相光催化降解LDPE复合膜的性能变化。结果表明:Fe-Sr₂Bi₂O₅在紫外光和可见光条件下对LDPE均具有较好的光催化降解能力,其中,紫外灯照射10 d后,Fe-Sr₂Bi₂O₅/PE复合膜断裂伸长保留率低于5%,拉伸强度保留率低于40%,接触角降低22.52°,已完全脆化;同时,LDPE复合膜中出现明显的羰基等降解特征吸收峰和降解孔洞;与Sr₂Bi₂O₅和TiO₂相比,Fe-Sr₂Bi₂O₅对LDPE具有更好的降解效果。综上所述,在紫外光和可见光条件下,Fe-Sr₂Bi₂O₅对LDPE具有明显的光催化降解作用,为未来光催化降解聚乙烯(PE)提供了一定的新依据。

Photocatalytic degradation of LDPE film with Fe-Sr2Bi2O5 photocatalyst under UV and visible light irradiation

A novel Fe-Sr₂Bi₂O₅ photocatalyst was synthesized with the co-precipitation method and added into a low density polyethylene (LDPE) film. The solid-phase photocatalytic degradation behavior of LDPE composite film under UV and visible light irradiation at room temperature was investigated and compared with the pure LDPE film, CaCO₃/PE,Sr₂Bi₂O₅/PE and TiO₂/PE composite films,and the obtained sample were characterized with contact angle, Fourier transform infrared spectroscopy (FT-IR) and field emission scanning electron microscopy (FESEM), including the analyses for the mechanical properties of reserved elongation at break and reserved tensile strength. Fe-Sr₂Bi₂O₅ had a high photocatalytic activity in degrading LDPE under UV light and visible light irradiation. After UV light irradiation for 10 d, reserved elongation at break and reserved tensile strength were lower than 5% and 40%, respectively; while contact angle was reduced by 22.52°. At the same time, carbonyl groups were detected in LDPE composite films and there were holes on the surface of LDPE around Fe-Sr₂Bi₂O₅. Fe-Sr₂Bi₂O₅ made photodegradation of LDPE more effective compared with Sr₂Bi₂O₅ and TiO₂ under UV or visible light degradation. In conclusion, LDPE could be degraded obviously by Fe-Sr₂Bi₂O₅ under UV and visible light irradiation at room temperature, and Fe-Sr₂Bi₂O₅ could be a new photocatalyst for photocatalytic degradation of polyethylene film in the future.