Vinyl-terminated methylphenyl silicone oil refers to silicone oil with vinyl in the end group and methyl and phenyl in the silicon atom on the main chain. According to the type of phenyl, it can be divided into methylphenyl chain type, diphenyl chain type and mixed type (containing two kinds of phenyl chain). Phenyl hydrogen-containing silicone oil is divided into hydrogen-terminated phenyl silicone oil and side hydrogen-containing phenyl silicone oil, which have different uses. The former is mainly used as a diluent or chain extender when added into the packaging adhesive, and the latter is mainly used as a concentrated cross-linking agent of the packaging adhesive, playing the role of cross-linking center. The preparation method of phenyl hydrogen-containing silicone oil is cationic polymerization, generally sulfuric acid. In order to reduce the process flow, acid resin can also be used for catalytic polymerization. The step of neutralizing the catalyst is omitted, and the acid resin is directly filtered out, and the acid resin can also be reused for many times.

Vinyl-terminated methyl phenyl silicone oil and phenyl hydrogen-containing silicone oil are the basic raw materials of high refractive index LED packaging adhesive. With the rapid development of LED industry, the LED packaging industry has unlimited potential, and the demand for phenyl silicone oil is huge. In recent years, with the further improvement of the production technology of domestic phenyl monomers and intermediates, the research of such products has made certain progress, but there is still a certain gap compared with foreign products, which needs to be improved. At present, the preparation technology and market of high refractive index LED packaging adhesives are monopolized by foreign organic silicon companies. Phenyl materials are the key to development and the focus of urgent research.