Nano-TiO₂ immobilized antioxidant (TiO₂-KH550-AG) was prepared to improve the ageing resistance of thermoplastic vulcanizate (TPV) exposed to UV/O₃. TiO₂ nanoparticles were firstly modified with 3-aminopropyltriethoxysilane (KH550) and then reacted with the antioxidant, 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid (AG), through the acyl chloride reaction followed by the amidation. FT-IR, XPS and TGA measurements confirmed that the antioxidant (AG) was chemically immobilized onto the nano-TiO₂ surfaces. TPV/TiO₂-KH550-AG nanocomposites were prepared by melt mixing. SEM observation showed that TiO₂-KH550-AG was homogeneously dispersed into the matrix of TPV. The UV/O₃ ageing test of the samples was carried out in the environment with constant UV intensity of 1.40 mW/cm² and ozone concentration of 100 ± 4 mg/m³. The ageing resistance behavior of the TPV/TiO₂-KH550-AG nanocomposites was evaluated by the changes of surface morphology, mechanical properties and carbonyl index during the UV/O₃ ageing test. It was observed that the TPV/TiO₂-KH550-AG exhibited high stability during the process of UV/O₃ ageing. The results revealed that the anti-ageing efficiency of TiO₂-KH550-AG was superior to the mixture of the corresponding AG and modified TiO₂, owing to the better dispersion and migration resistance of TiO₂-KH550-AG.

制备了纳米TiO ₂固定型抗氧化剂（TiO ₂ -KH550-AG），以提高暴露于UV / O ₃的热塑性硫化橡胶（TPV）的耐老化性。首先用3-氨丙基三乙氧基硅烷（KH550）修饰TiO ₂纳米粒子，然后通过酰氯反应与抗氧化剂3-（3,5-二叔丁基-4-羟苯基）丙酸（AG）反应酰胺化。FT-IR，XPS和TGA测量证实，抗氧化剂（AG）已化学固定在纳米TiO ₂表面上。通过熔融混合制备TPV / TiO ₂ -KH550-AG纳米复合材料。SEM观察表明TiO ₂-KH550-AG均匀分散在TPV的基质中。在恒定的紫外线强度为1.40 mW / cm ²且臭氧浓度为100±4 mg / m ³的环境中进行样品的UV / O ₃老化测试。通过UV / O ₃老化试验中表面形貌，力学性能和羰基指数的变化，评估了TPV / TiO ₂ -KH550-AG纳米复合材料的耐老化性能。观察到TPV / TiO ₂ -KH550-AG在UV / O ₃老化过程中表现出高稳定性。结果表明，TiO ₂的抗老化性能-KH550-AG由于TiO ₂ -KH550-AG具有更好的分散性和抗迁移性，因此优于相应的AG和改性TiO ₂的混合物。