Kemeng Liu, Xueying Wen, Huiyue Wang, Huajian Liu, Lijie Liu, Ran Niu, Tao Tang, Nan Yao*, Ruikun Pan*, Jiang Gong*

Catalytic upcycling of silicone rubber by AlCl₃ at low temperature

Polymer Degradation and Stability 232 (2025) 111117. (IF2024 = 6.3)

Chemical recycling of silicone rubber (SR) waste into valuable products has aroused ever-increasing attention; however, the development of a green, efficient degradation strategy for silicone rubber remains challenging. In this work, we report the catalytic upcycling of silicone rubber by AlCl₃ to produce SiO₂ under atmospheric environment. The optimized AlCl₃/SR mass ratio, reaction temperature and time are 0.75, 280 ℃ and 120 min, respectively. The maximum yield of SiO₂ is 96 %. The as-prepared SiO₂ displays irregular spherical agglomerates with a particle size of 20–30 nm and bears rich micropores/mesopores/macropores. The result of variable-temperature Fourier-transform infrared spectroscopy proves that AlCl₃ promotes the fracture of Si-O in SR during heating. According to density functional theory, the addition of AlCl₃ leads to a decrease in the bond dissociation energy of Si-O and Si-C. The strategy achieves the green, efficient catalytic degradation of silicone rubber waste.