The prospects for in-depth processing of silicone materials are promising

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“During the 12th Five-Year Plan period, the silicone industry must accelerate the transformation of its development model, vigorously promote structural adjustment, technological innovation, and energy conservation and emission reduction, gradually establish a modern green and low-carbon industrial system, and continuously enhance the industry’s core competitiveness. In the **Guidance Catalog for Industrial Structure Adjustment (2011 edition) issued by the National Development and Reform Commission, the organosilicon products classified as those that are encouraged include: new types of organosilicon monomers such as phenylchlorosilane and vinylchlorosilane; siloxanes such as phenylsilicone oil, amino silicone oil, and polyether-modified silicone oil; high-performance rubbers and hybrid materials such as phenylsilicone rubber and polyphenylsilicone rubber; high-performance resins such as phenylsilicone resin; and a range of efficient coupling agents such as triethoxysilane.** In addition, the comprehensive utilization of by-products such as carbon tetrachloride, silicon tetrachloride, methylchlorosilane, and trimethylchlorosilane is also included in the list of **industries that are encouraged. 　　It is worth noting that single-unit methylchlorosilane monomer production facilities with a capacity of less than 100,000 tons per year are classified in the restricted category of the \"Adjustment Catalogue\". This means that in the future, small-scale producers of silicone monomers will not be able to enter the industry. In line with **policy guidelines, over the long term, the development of the silicone industry will move in the direction of larger-scale production and deeper processing. Among large-scale enterprises, ST New Materials is the most noteworthy ； In the field of deep processing, Hongda New Materials is already in a leading position. 　　There is a significant shortage of high-end silicone rubber products. For mid- and low-end products, the supply exceeds demand; therefore, capacity expansion will be restricted, and there is an excessive capacity for dimethyl monomer. In recent years, the apparent consumption of siloxanes in China has been growing at an average annual rate of 15%. Based on this trend, it is estimated that by 2015 the apparent consumption of siloxanes in China will reach 1.12 million tons, while the total production capacity is expected to increase to 1.4 million tons. In recent years, as the domestic supply capacity of silicone monomers has continued to grow, market competition has become increasingly fierce. Since 2005, the gross profit margins of various silicone monomer manufacturers in the industry have shown a long-term downward trend. For example, Lanxing New Materials had a gross margin of 42% on its silicone products in 2005, but this figure has dropped to around 10% in recent years. 　　High-quality silicone oil products remain scarce. Silicone oil is typically a linear polysiloxane product that remains in a liquid state at room temperature; it is produced by hydrolyzing, cracking, and refining dimethyldichlorosilane, then adding sealants and modifiers, followed by vacuum distillation. Silicone oil is commonly used as a high-grade lubricant, shock-absorbing oil, insulating oil, defoamer, release agent, polishing agent, separator, and oil for vacuum diffusion pumps. Emulsions can be used for polishing automobile tires and dashboard surfaces. After emulsification or modification, silicone oils can also be used in textile finishing to impart a smooth and soft feel; emulsified silicone oils are added to shampoos in daily care products to enhance the lubricity of hair. In addition, there are also ethyl silicone oils, **-based silicone oils, nitrile-containing silicone oils, polyether-modified silicone oils (water-soluble silicone oils), and so on. 　　The production process of silicone oil is relatively simple; as a result, the production of silicone oil products in China, especially ordinary silicone oil products, has reached a certain scale. The current total production capacity is around 100,000 tons (calculated on a siloxane basis). The scale of silicone oil production facilities in China is generally small; those with an annual production capacity of over 1,500 tons include Lanxing Xinghuo, Xinan Co., Zhaoyang Sihai, Xiamen Hanxu, Shenzhen Tianding, Changzhou Hongxing, and Yangzhou Chenguang, among others. The product quality is also mostly at the mid-range or low-end level; high-quality silicone oils still need to be imported. The main reason why high-quality silicone oils are difficult to produce domestically is that the quality of dimethyl monomers fails to meet the required standards. At the same time, it is difficult in China to produce certain special monomers that can improve the quality of silicone oils, such as **base monomers. 　　There is a huge gap in high-end silicone rubber products. Silicone rubber is divided into two main categories: high-temperature silicone rubber and room-temperature silicone rubber. High-temperature silicone rubber is mainly used to manufacture various silicone rubber products, while room-temperature silicone rubber is primarily used as adhesives, potting materials, or in molds. High-temperature silicone rubbers are further divided into methyl silicone rubber (MQ), methyl vinyl silicone rubber (VMQ, the most widely used and available in the largest range of product grades), and methyl vinyl phenyl silicone rubber PVMQ (resistant to low temperatures and radiation). Other types include fluorosilicone rubber and perfluorosilicone rubber. Currently, the total production capacity of silicone rubber in China exceeds 500,000 tons, of which 300,000 tons are for high-temperature silicone rubber and over 200,000 tons for room-temperature silicone rubber. The products manufactured by domestic high-temperature silicone rubber producers are mostly of mid-to-low quality; there is a significant shortage of high-end products, and nearly 50,000 to 100,000 tons of high-temperature silicone rubber products need to be imported each year to meet demand. The reason is the poor quality of upstream silicone monomer products, as well as the lack of special silicone monomers. Silicone resin manufacturers are relatively small in scale; those with a production capacity of over 1,000 tons include Jiangsu Sanmu, Zaoyang Sihai, Shanghai Resin Factory, and Zhonglan Chenguang. 　　Phenyl monomers remain an unexplored field in China. Phenyl monomers can significantly improve the properties of silicone materials. Silicone monomers mainly include methylchlorosilane (referred to as methyl monomer), phenylchlorosilane (referred to as phenyl monomer), methylvinylchlorosilane, ethyltrichlorosilane, propyltrichlorosilane, vinyltrichlorosilane, γ-chloropropyltrichlorosilane, and fluorosilicone monomers, among others. Among them, methylchlorosilane is the most important, accounting for over 90% of the total amount of monomers, followed by phenylchlorosilane. At present, the production of methylchlorosilane in China has reached a certain scale, and the product quality can meet the needs of general applications. How to develop high-performance new silicone monomers, especially phenyl monomers, has become an important challenge for the domestic silicone industry. 　　Phenylchlorosilane is a widely used intermediate. It can be used to prepare various coupling agents, and is also one of the important monomers for the production of silicone polymers. Among silicone monomers, its usage and importance rank second, just after methylchlorosilane. 　　Methyl vinyl phenyl silicone rubber, abbreviated as phenyl silicone rubber, is produced by introducing diphenyl siloxane units (or **phenyl siloxane units) into the molecular chains of vinyl silicone rubber. Domestically produced phenyl silicone rubbers are mainly dimethyldiphenylvinyl silicone rubbers, which are typically synthesized by the rearrangement of diphenyl-containing cyclosiloxanes, dimethylcyclosiloxane, and methylvinylcyclosiloxane under basic catalysis. **Silicone rubber can be used in applications requiring resistance to high and low temperatures, and serves as a key material for components in aerospace, aviation, electronics, engines, and industrial cryogenic equipment. 　　**Phenylsilicone oil is produced using diphenyldichlorosilane and dimethyldichlorosilane as raw materials, with trimethylchlorosilane as a chain terminator, through processes such as hydrolysis and copolymerization catalyzed by alkalis and tetramethylammonium hydroxide. **The main characteristics of silicone oils are their high oxidation stability and resistance to radiation. It can be used as a heat treatment bath and high-temperature heating oil for metal products, as well as a lubricant for high-temperature fan bearings, ball bearings, automobile engines, textile dryers, etc. Furthermore, it is also widely used in hydraulic instruments, electrical insulation, and other areas. 　　**Phenylsilicone resins are primarily formed by the hydrolytic polycondensation of methyltrichlorosilane, dimethyldichlorosilane, phenyltrichlorosilane, and diphenyldichlorosilane. **Silicone resins are primarily used as impregnating varnishes for H-class motor and transformer coils, as high-temperature resistant coatings, and as impregnating materials for H-class insulating laminates, tubes, and rods in the electrical industry. They can also be transformed into reactive silicone resins with a low molecular weight and active functional groups, which are used to modify polyester, epoxy, phenolic, alkyd, and other types of silicone resins. 　　In recent years, with further improvements in the production technologies for **basic monomers and intermediates domestically, progress has been made in the research on such products. However, there is still a certain gap compared to foreign products. It is necessary to further intensify research on **monomer synthesis and separation technologies in order to improve the yield of **dichlorosilanes and the purity of the products. At the same time, expand the production scale of downstream **polydimethylsiloxane-based product lines, as well as research on new varieties and new synthesis processes, in order to broaden their application areas. In terms of production, in recent years only a few companies in the country have established modest production capacities for phenylsilicon monomers, with a total capacity of around 5,000 tons. The equipment in most enterprises operates very unstably, preventing continuous production; moreover, indicators such as product purity are at low levels. In the field of phenyl monomers, the domestic market is still relatively undeveloped. Due to the vast range of applications for phenyl-based products, the domestic market demand is currently met by foreign products. Based on the 1:20 ratio between the demand for phenyl-based products and methyl-based products, the domestic market demand for phenylsilane products is estimated to be around 50,000 tons per year.