Application of titanium dioxide nanorod (TNr)@SiO₂ with low photocatalytic effect and high UV resistance in poly(vinyl chloride) film

Abstract

Ultraviolet (UV) radiation has a detrimental effect on the outdoor lifetime of PVC film materials. TiO2 nanoparticles, as commonly used UV absorbers, still suffer from poor transparency, high photocatalytic effect, and poor dispersion in PVC matrix. To mitigate these effects effectively, titanium dioxide nanorod @ silicon dioxide (TNr@SiO2) was synthesized and used as an anti-UV aging agent for polyvinyl chloride (PVC). The agglomeration effects of TiO2 nanoparticles in PVC films were solved by synthesizing TNr, and the catalytic effects of TiO2 was reduced by growing SiO2 on the TNr surface. Scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and UV-visible spectroscopy were utilized to demonstrate the excellent dispersion and low photocatalytic effects of the synthesized TNr@SiO2. Compared with pure PVC film, the color change of TNr@SiO2/PVC composite film is not evident after 800h of UV aging, and the retention of mechanical properties were 93.94%. Compared with TiO2/PVC, TNr@SiO2/PVC composite film has better transparency. Results show that TNr@SiO2 can maintain the properties of PVC better because the electrons of TNr@SiO2 are excited to form a positively charged hole after the absorption of UV light, and then the hole electron pairs are recombined and converted into thermal energy, which improves the durability of PVC. Therefore, this highly transparent TNr@SiO2/PVC composite film with low photocatalytic activity and high UV resistance will soon be applied in large-scale industrial production.