废旧硅橡胶酸催化降解的行为研究

Study on acidic catalytic degradation of waste silicone rubber

废旧硅橡胶的回收利用对资源重复利用以及环境保护有重要意义。主要研究了废旧硅橡胶在对甲苯磺酸做催化剂时的降解行为。在甲醇有机体系中加入对甲苯磺酸催化降解废旧硅橡胶为硅氧烷的低聚物。主要讨论了反应溶剂、回流时间和对甲苯磺酸用量对降解产物回收率的影响。通过对反应条件进行单因素及因子设计,获得最优制备工艺。对降解产物进行气相色谱-质谱和红外光谱的表征。结果表明:产物主要为小分子环状硅氧烷,其中主要组分为环四硅氧烷(D_4)和环五硅氧烷(D_5)。

Recycling of waste silicone rubber is of great significance to the resource reuse and environmental protection.The degradation behavior of waste silicone rubber used p toluene sulfonic acid as catalyst was mainly studied.By adding p-toluene sulfonic acid in the organic system of methanol,the silicon oligomers were produced by the catalytic degradation of waste silicon rubber.The effects of reaction solvent, reaction time and p-toluene sulfonic acid on the recovery rate of degraded products were mainly discussed.The optimum experimental conditions were obtained by single factor and factor design of reaction conditions.The degraded products were characterized by gas chromatography＂ mass spectrometry,infrared spectroscopy and gel chromatography.The products was small molecular cyclic siloxanes, mainly including cyclotetrasiloxane （D4） and cyclopentasiloxane （D5）.