Semi permanent mold release agent, the main body of which is silicon and fluorine-containing compounds, has low surface energy, high thermal stability and chemical stability, so it has high surface activity, high thermal stability and high chemical inertia. Compared with other types of release agent, the advantages of this kind of release agent are: stable quality of release agent itself, long product storage period; low concentration dilution use, and good continuous release effect; good release performance for high viscosity materials and products, and the mold and products are basically free of contamination after release, the mold does not need to be cleaned, and does not affect the secondary processing of products.
The crosslinkable silicone resin with silicon hydrogen bond was synthesized by using 1,1,3,3- tetramethyldihydrodisiloxane(TMDSO), methyl trimethoxysilane, phenyl trimethoxysilane and ethyl orthosilicate as raw materials. The room temperature curing semi permanent silicone release agent was prepared by using crosslinkable silicone resin, hydroxyl silicone oil and catalyst. The release performance and stability of the release agent were improved by changing the type and content of each component in the release agent. The results showed that the viscosity of crosslinkable silicone resin was about 5-8 PAS, the ratio of silicone resin to modified hydroxy silicone oil was 3:2, the amount of amine catalyst was 0.5-0.75%, the solid content of solvent type silicone release agent was 5%, the surface contact angle was about 90 °, The release performance and stability of the release agent are the best. The coated film can be cured rapidly at 25 ℃ at room temperature. The number of times of release can reach more than 20. After multiple times of release, the stripping force is still lower than 6N / cm. When the dilution is 1%, the number of release can still reach 9 times. It has good stability. After 60 days at room temperature, there is no gel and precipitation.