Typical silicone resins are organosilicon polymers with active reactive groups. In order to improve the hardness of silicone resin curing materials, the following two means are commonly used: ① improve the functional degree of silicone polymer, that is, reduce the R/Si value of silicone resin components; ② Silicone polymer side chain group all use the shortest chain organic group - methyl, and avoid the use of phenyl side chain group.
Synthetic high crosslinking degree, especially the high crosslinking degree of methyl silicone resin, difficult control of synthetic reaction process, the main problem is the synthetic reaction of silicon resin solution, easy to produce gel component in the silicon resin solution is often found in gelatin gel particle, which is often caused by silicone gel particles solution during the storage period continue condensation crosslinking activity center; The gel particles generated during the synthesis process not only damage the storage stability of the silicone solution, but also may form "fish-eyes" or "crystal points" in the coating during application, leading to optical distortion and reduced light transmittance of the silicone film, which seriously damages the performance of the silicone resin.
The presence of such gel centers must be avoided in order to produce high cross-linking methyl silicone resins with stable storage. Its technology is the key to effective control of hydrolytic condensation reaction stable equilibrium, the feasible technical method is to use a mild moderate catalyst and controllable synthesis process, control process of hydrolytic condensation reaction of organic silicon monomer, avoid too much "beat" four faculties monomer hydrolysis and condensation "alone", so as to prevent formation of gel center, and get the structure stability of the polymer.