TiO2对聚氯乙烯紫外光稳定与催化降解的影响

综述了普通和纳米TiO_2对聚氯乙烯(PVC)的紫外光稳定和催化降解的机理及研究进展,以及包覆和掺杂改性对TiO_2光稳定和光催化性能的作用。金红石型纳米TiO_2具有优异的紫外光稳定特性,锐钛型纳米TiO_2表现出极强的光催化活性。无机包覆过的金红石型TiO_2对PVC有明显的保护作用。有机改性则能提高锐钛型TiO_2的分散性,从而提高其对聚合物的光催化效率。过渡金属离子掺杂可在TiO_2晶格中引入缺陷位置或改变结晶度,从而改变PVC的光降解速率。

The influence of TiO2 on the photostability and photocatalysis of PVC

The action mechanisms and research advances of both commercial and nano-TiO_2 (rutile and anatase) in the photostability and photocatalysis of poly(vinyl chloride) (PVC) were reviewed in this paper.At the same time,the photostable and photocatalytic performance of TiO_2 modified by doped and coated were summarized. The rutile form has an excellent stabilizing effect on photodegradation whereas anatase form has a photocatalytic effect on the photodegradation of PVC.The greatest protection to PVC is offered by TiO_2 (rutile) particles coated with inorganic compounds.The photocatalytic performance of TiO_2 (anatase) to polymer is improved by surface modification with organic compounds,which can improve the dispersion of pigment.The photodegradation rate of PVC is changed by doped with a range of transition metal ions,which can import the defect positions in crystal lattice or change crystallinity.