Silicone adhesives can be classified into silicone-based adhesives and silicone rubber-based adhesives based on raw material sources. The former is mainly used for bonding metals and heat-resistant non-metallic materials. The resulting adhesive parts can be used at -60. It is used in the temperature range of °C ~ 200 °C; the latter is mainly used for bonding heat-resistant rubber, rubber and metal and other non-metallic materials. Since the 1960s, room temperature vulcanized silicone rubber has gradually developed.

The conventional silicone resin is a cross-linked synthetic polymer mainly composed of silicon-oxygen-silicon, and is classified into a methyl silicone resin, a phenyl silicone resin, a methylphenyl silicone resin, etc. depending on the linking group on the silicon atom. According to the different curing methods of cross-linking, it is divided into condensation type, polymerization type, addition molding and so on. The number of functional groups in the silicone resin is different, the substituents are different, and the degree of polymerization, the degree of branching and the degree of crosslinking are different, and the properties of the products are different, and the products are adapted to different uses.

Generally, the R/Si of the silicon monomer is between 12 and 15. Above this value, the cured silicone resin has poor strength and flexibility, and below this value, the crosslinking degree is high, and the silicone resin is hard and brittle. The cured silicone resin has a glass transition temperature (Tg) of >200 °C. The phenyl content in the methylphenyl silicone resin has a great influence on the condensation rate and hardness of the product. The inclusion of a phenyl group improves the thermoelasticity of the product and its compatibility with the pigment and its thermal stability. Phenyl silsesquioxane (ie, silicon ladder polymer) [C6H5SiO1 5]n is a trapezoidal polymer with outstanding heat resistance and begins to lose weight when heated to 525 ° C in air.

The trapezoidal polymer with silicon as the main chain has excellent heat resistance and can withstand heat at 1300 ° C and still has a certain strength at 1250 ° C. The linear cyclic silicon nitride polymer does not decompose at 450 to 480 ° C and can be used at 450 ° C for a long time. The siloxane backbone introduces various aromatic heterocyclic rings or other heat-resistant cyclic structures and heteroatoms to improve its overall properties without degrading its heat resistance. The cage structure of the decaborane structure is introduced into the polyorganosiloxane backbone, which reduces the active rotation of the chain links, increases the rigidity, and increases the glass transition temperature.

The introduction of the aromatic ring significantly changes the heat resistance, and the adhesion properties, cohesive strength, and radiation resistance are significantly changed. The arylene group such as phenylene, diphenyl ether subunit and biphenyl subunit is added to the main chain, which has strong radiation resistance and high temperature resistance up to 300-500 °C. The introduction of a butyl group on the siloxane backbone increases the compatibility with alkyd resins, polyester resins, etc.; introduction of phenyl groups can improve the product's thermoelasticity, pigment compatibility, adhesion and Thermal stability. The best self-extinguishing flame retardant silicone rubber sealant can be obtained by introducing a suitable phenyl group (7% to 20% by mole). The introduction of a heterocyclic ring has a very good dielectric property. The ferrocene structure is introduced and has electrical conductivity. The introduction of various hetero atoms such as Al, B, Ti, and Sn improves the heat resistance, adhesion, and self-adhesive properties. The side chain structure is changed, and a cyanoethyl group, a γ-trifluoropropyl group, an aliphatic amine group, an aromatic amine group, a chloromethyl group, an epoxy group or the like is introduced to improve oil resistance, adhesion property and cohesive strength.