空气氛围中硅橡胶热解气态产物释放规律研究

Study on the Release of Gaseous Products from Silicone Rubber Pyrolysis in Air Atmosphere

为更好的实现气体组分分析法在中压开关柜局部放电检测这一领域的应用,文章对改性甲基乙烯基硅橡胶进行空气氛围中热解气态产物释放规律研究。得出以下结论:改性甲基乙烯基硅橡胶在空气氛围中200℃~800℃热解温度下,生成的气态产物种类较多,主要包括氢气、一氧化碳、二氧化碳、烷烃、烯烃、杂环类物质、酮、醇、醛、卤代烃、苯系物、烷烃、杂环芳烃、链状及环状硅氧化合物;改性甲基乙烯基硅橡胶在空气氛围中200℃~800℃热解温度下,整体上随着热解温度的增加改性甲基乙烯基硅橡胶主链结构被破坏后,先生成大量相对分子质量较高的大分子物质和少量小分子物质,随着热解温度的升高,大分子物质与小分子物质之间发生复杂的化学反应而相互转化,并且经过复杂的化学反应后大分子物质会转化为相对稳定的小分子物质。在300℃~600℃热解温度下,相对分子质量较高的链状及环状硅氧化合物生成速率低于分解速率,相对分子质量较高的链状及环状硅氧化合物分解为相对分子质量较低的链状及环状硅氧化合物。

In order to realize the application of gas component analysis method in partial discharge detec-tion of medium-voltage switchgear, the release law of gas products from pyrolysis of modified methylvinyl silicone rubber in air atmosphere was studied. The following conclusions are drawn: the modified methylvinyl silicone rubber produces a wide range of gaseous products, including hydrogen, carbon monoxide, carbon dioxide, alkanes, alkenes, heterocyclic substances, ketones, alcohols, aldehydes, halogenated hydrocarbons, benzene series, alkanes, heterocyclic aromatic hydrocarbons, chain and cyclic silica compounds, at the pyrolysis temperature of 200˚C to 800˚C in an air atmosphere. Modified methylvinyl silicone rubber in the air atmosphere at 200˚C~800˚C pyrolysis temperature, as a whole with the increase of pyrolysis temperature modified methylvinyl silicone rubber main chain structure is destroyed, the formation of a large number of relatively high molecular weight macromolecular substances and a small number of small molecular substances, with the rise of pyrolysis temperature. Complex chemical reactions occur between large analytical substances and small molecular substances, and the large molecular substances will be transformed into relatively stable small molecular substances after complex chemical reactions. At the pyrolysis temperature of 300˚C to 600˚C, the generation rate of the chains and cyclic silico compounds with higher molecular weight is lower than the decomposition rate, and the chains and cyclic silico compounds with higher molecular weight decompose into the chains and cyclic silico compounds with lower molecular weight.