Properties and Applications of Silicones and Synthesis Process of Methylchlorosilanes

Silicones feature a unique molecular structure and combine the dual properties of inorganic and organic materials. They not only possess fundamental characteristics such as low surface tension, a small viscosity-temperature coefficient, high compressibility and excellent gas permeability, but also exhibit outstanding properties including resistance to high and low temperatures, electrical insulation, oxidation stability, weather resistance, flame retardancy, hydrophobicity, corrosion resistance, non-toxicity, odorlessness and physiological inertness. For these reasons, they are widely used in numerous industries such as aerospace, electronic and electrical engineering, construction, transportation, chemical engineering, textile, food, light industry and medical care.

The core of preparing silicone materials lies in methylchlorosilanes, the silicone monomers. Its main synthesis methods include the Grignard method, organolithium method, condensation method and direct method, among which the direct method is currently the only industrial production method for methylchlorosilanes. The specific process route is as follows: first, silica ore with a silica mass fraction of more than 99% is subjected to carbon reduction at 1400℃ and cooled to obtain silicon ingots; the silicon ingots are crushed and ground into silicon powder with a specific particle size; the silicon powder then undergoes a direct reaction with methyl chloride (CH₃Cl) to complete the synthesis of methylchlorosilanes. This process suffers from high energy consumption and heavy pollution, and also entails high operational and maintenance costs for equipment.