Simultaneous Enhancements of Ultraviolet-Shielding Properties and Thermal Stability/Photostability of Poly(vinyl chloride) via Incorporation of Defect-Rich CeO<sub>2</sub> Nanoparticles
Zequan Hu, Si Wang, Xin Zhang, Guoli Fan, Yingdi Lv, Xiaodong Zheng, Lan Yang, Feng Li
Abstract
In the present work, CeO2 nanoparticles with abundant surface defects and controlled particle size were synthesized by separate nucleation and aging steps followed by a calcination treatment and applied as a multifunctional additive for the preparation of a PVC–CeO2 composite film. The characterization results demonstrated that the as-prepared PVC–CeO2 composite film could completely block UV-C, 98.6% UV-B, and more than 50% UV-A with high transparency in visible light; meanwhile, its initial pyrolysis temperature could be put off by 16 °C compared to that of pristine PVC. Density functional theory calculations and experimental results revealed that the enhanced thermal stability/photostability of PVC–CeO2 composite films is mainly attributed to the close interaction and good compatibility between the CeO2 nanoparticle and PVC matrix, enhanced HCl-capture capability of highly dispersed CeO2 nanoparticles, and the formation of the coordinate complex between Ce atoms in defect-rich CeO2 and labile Cl atoms in PVC main chains. Furthermore, the excellent UV absorption capacity of CeO2 nanoparticles could endow the PVC–CeO2 composite film with significantly improved UV-shielding efficiency. This work provides a new clue for the rational design and synthesis of rare earth-based additives, which are expected to be used in polymers, especially in PVC-based functional materials.