PVC, which is used as one of the most widely polymer, the general purpose plastic in industry, agriculture, household items and many other fields because of abrasion resistance, sound/
thermal insulation and low cost [1–4]. The global PVC consumption in 2020 is 49.5 million tons and grows sustainably with a rate of 5% per annum [5]. Nevertheless, PVC can easily degrade under heating or ultraviolet (UV) light radiation because of its structural features and inherent composition, causing PVC to turn from white to yellow, and even black, finally limited the application range of the materialist [6, 7]. Therefore, the addition of thermal and UV stabilizers is fundamental for improving the stability of PVC materials [8]. It is greatly urgent to explore a novel nontoxic multifunctional stabilizer that can dramatically enhance the protective materials and thermal stabilizers including polymeric additives or inorganic agents UV stability of PVC. On the other hand, from the environmental point of view, addition of thermal stabilizers in PVC also is considered critical [9]. In recent years, various UV were developed to dispute the pyrolysis of PVC and reduce the damage about UV irradiation resulting from direct sunlight exposure or any others. UV protective materials also show prominent UV blocking capability by combining with polymers. Up to present, nanocomposites composed of polymers with inorganic-organic UV absorbers have shown a bright future for using as UV shielding materials. Generally, various inorganic or organic UV-shielding agents have been developed as additives to protect PVC from UV aging [10–12]. However, the high photo catalytic activity of inorganic absorbers (for example ZnO), narrow UV absorption region and poor photo stability of organic absorbers are bottleneck problems to be solved [13, 14], what's more, some of them are restricted for their toxicity or high cost [15–18].
Inorganic UV shielding materials are more favorable in comparison with organic UV materials due to their chemical stability, high optical, wide shielding range. CeO2 is one of the most crucial rare earth oxides with a small band gap (3.1 eV), which is conducive to the transition of CeO2 valence electrons. It is proved that CeO2 is a better ultraviolet radiation absorbent and has advantages in nontoxic, ecofriendly, photo-stability, and low cost, which has various applications in industry, luminecent materials and sensors due to its diverse crystalline structure and individual physicochemical properties [19–21]. Small particles such as nanoparticles have been widely used in the fields of the bioimaging and sensing, et al. All of these applications will depend largely on the particle shape, size, surface function, which determine the photoelectric and chemical properties of the nanoparticles. Driven by various applications, and the excellent properties, the development of effective methods to synthesize nanostructures with size/shape control is one of the key trends in materials science [22]. Quantum dot (QDs) with narrow size distribution which attract much attention of scientists because of the high efficiency luminescence, since these could be widely used in the areas of UV-shielding [23]. In addition, compare to ZnO, CeO2 has higher transparency to visible light and prominent UV shielding properties and is expected to used as UV protectors or ideal multifunctional additive [24, 25]. Nevertheless, CeO2 QDs is difficult to disperse homogeneously within polymer matrix as UV-shielding materials and it is very limited to researched on CeO2 as a function additive for PVC so far [26]. Therefore, this work is aimed to synthesis functionalized CeO2 QDs, EDHB was used for surface modification of CeO2, then homogeneously dispersed into the PVC matrix to preparate polymeric films. And finally, UV‑shielding properties and thermal stabilizer of films were tested. Two different sources of PVC degradation were considered: the higher temperatures and UV light radiation, which is used outdoor exposure of materials based PVC. The results obtained were compared to pure PVC, the composite films showed an improvement ultraviolet shielding and thermal stability.