聚丙烯基纳米复合材料的制备及其光稳定性和耐老化性能评价OA

Polypropylene(PP)-based nano-TiO2 composites were prepared via silane coupling agent modification and in-situ polymerization,and their photostability and aging resistance were systematically investigated.The results showed that silane coupling agent modification significantly improved the dispersibility of nano-TiO2,and the modified nanoparticles maintained a stable dispersed state in toluene for 72 h.When the mass fraction of TiO2 was 2.0%,the tensile strength and elastic modulus of the PPT2.0 composite increased by 22.6%and 28.5%,respectively.PPT2.0 retained 86.7%of its tensile strength and 71.2%of its impact strength after 800 h of aging,with a carbonyl index of only 0.31.A 12-month outdoor exposure test further verified the long-term protective effect of nano-TiO2 the retention rates of tensile strength and impact strength of PPT2.0 reached 78.5%and 72.3%,respectively.By establishing a multi-level synergistic protection mechanism model,the synergistic effects of UV shielding,radical scavenging,and physical barrier mechanisms were revealed,providing a reference for the development of high-performance aging-resistant polymer materials.