Among the organic silicon polymers, they are mainly used in the fields of practical application and extensive application. They are mainly composed of organic silicon monomers (such as organohalosilanes), which have been hydrolyzed and condensed to form silicon-oxygen bonded macromolecular organosilicon compounds. The main chain is composed of silicon oxygen bonds, the side chain is connected to the organic groups via silicon atoms and is called polyorganosiloxane. Silicone resin is a class of polyorganosiloxane molecular weight thermosetting resin. Glass fiber reinforced composites made of such resins retain excellent electrical properties even after prolonged use at higher temperatures (200-250 ° C) for extended periods of time, and have good arc resistance and hate resistance Waterproof performance.
(1) thermal stability. Silicone resin Si-O bond has a high bond energy (363kJ / mol), so more stable, heat resistance and high temperature performance are high. In general, its thermal stability range up to 200 ~ 250 ℃, a special type of resin can be higher.
(2) mechanical properties. Mechanical properties of the cured silicone resin is not high, if the introduction of chlorophenyl in the main chain of macromolecules can improve the mechanical properties. Silicone resin fiberglass laminates have poor interlaminar bond strength and a significant decrease in flexural strength when heated. If the main chain into the phenylene, can improve the rigidity, strength and temperature. (3) Electrical properties. Silicone resin has excellent electrical insulation properties, and its breakdown strength, high voltage arc and spark performance are superior. By the arc and EDM role, even if the resin to crack the organic groups removed, the surface of the remaining silicon dioxide also has good dielectric properties.
(4) Hydrophobicity. Silicone resin water absorption is very low, water droplets on its surface can only be rolled and can not be wetted. As a result, silicone resin fiberglass reinforced composites retain their excellent properties under humid ambient conditions.
(5) Corrosion resistance. Silicone resin fiberglass reinforced composites can be concentration (mass)
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