Study On Preparation And Properties Of Phenyl Silicone Rubber And Its Intermediates

Methyl phenyl silicone rubber(referred to as phenyl silicone rubber)has excellent aging resistance,radiation resistance,high and low temperature resistance,burn resistance,high damping,high refractive index and other properties.It is widely used in high-end fields and extreme occasions such as aerospace,nuclear power equipment,etc.The preparation process of methyl phenyl silicone rubber is complicated,involving the preparation of octaphenyl ring,the preparation of polymethyl phenyl siloxane,the preparation of methyl phenyl mixed ring body,and the synthesis of silicone rubber.At present,phenylsilanol,which is the raw material for the production of octaphenyl ring,has been poorly vulcanized and has decreased performance due to changes in the production process,under the condition that the production process and indicators of the subsequent sections remain unchanged.For this reason,this article carried out the preparation of polymethylphenylsiloxane and methylphenyl mixed ring under the condition that the raw materials such as octaphenylcyclotetrasiloxane and octamethylcyclotetrasiloxane remain unchanged.The research of the various process conditions of methyl phenyl silicone rubber polymerization,especially the exploration of the preparation process of the methyl phenyl mixed ring,has improved the performance of the key intermediate,and the performance of the final product methyl phenyl silicone rubber Ascension,the structure characterization and key performance determination of each intermediate product were carried out.This article focuses on the study of the effects of pyrolysis conditions on the transparency,refractive index and yield of the fraction(product)and other key performance and indicators;and compares the equilibrium polymerization and pyrolysis split operation process with the integrated operation process.The results show that the mixed ring prepared by the integrated preparation method of equilibrium and pyrolysis and the temperature and pressure pyrolysis process has the best performance.The prepared methyl phenyl mixed ring has a yield of 71.24%,a refractive index of 1.496,and a transmittance of 97%(?=550 nm),and its performance is close to similar high-quality products from suppliers.Secondly,it mainly studies the preparation and performance factors of methyl phenyl silicone rubber.The silicone rubber(raw rubber)prepared by the above methyl phenyl mixed ring can effectively control its viscosity,and the transmittance is higher than 95.0%(?=550 nm)),the yield is higher than 96.0%.Finally,the preliminary vulcanization study of methyl phenyl silicone rubber was carried out,and the preliminary raw material synthesis process for the preparation of the mixed ring body was also studied.