有机硅材料凭借优异的耐高低温性、耐候性、电绝缘性、生理惰性等特点,广泛应用于航空航天、国防军工以及国民经济各领域。研究有机硅材料的解聚行为有助于耐高温硅橡胶的设计开发和废旧有机硅材料的绿色回收。综述了有机硅材料的降解机理,主要包括催化降解(亲核体、亲电体)和热降解(侧基热氧化降解、主链拉链式降解、主链无规重排降解)机理,介绍了抑制以及促进有机硅材料降解的主要方法,旨在提高聚硅氧烷的热稳定性以及实现废旧有机硅材料的回收利用。
Silicone materials have been widely used in aerospace,national defense industry and various industries of the national economy due to their excellent properties,such as high and low temperature resistance,weather resistance,electrical insulation,physiological inertness.The study of its depolymerization behaviour is helpful for the design and development of high-temperature resistant silicone rubber and the green recycling of waste silicone materials.The degradation mechanisms of silicone materials were reviewed,which mainly including catalytic degradation (nucleophiles,electrophiles) and thermal degradation (side-group thermo-oxidative degradation,main-chain zipper degradation,and main-chain random rearrangement degradation).The main approaches to inhibit and promote the degradation of silicone materials were described,aiming at improving the thermal stability of polysiloxanes and realizing the recycling of waste silicone materials.
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