Modified organosilicon polymer is the main basic polymer of single component organosilicon sealant. It is usually an organic polymer with organosilicon alkyl group, namely MS gel. The product has the characteristics of coating adhesion, good adhesion of polyvinyl chloride to copper sheet, strong anti-mildew and so on. Widely used in automotive, vehicle, electrical and other sectors, so the demand is very large. Its raw materials are allyl ether alcohol and methyl dimethoxysilane. The following picture shows the preparation process of MS glue.
MS glue with allyl ether alcohol as raw material is cured by modifying the formulation of organosiloxane, condensation catalyst and other materials. It reacts with moisture in air, crosslinks from the surface, gradually hardens, and finally forms a rubber-like elastomer. The following figure shows the curing mechanism of MS adhesive.
Here are several other structures of MS glue:
1. Carbamate vinegar prepolymer with terminal isocyanate group was prepared by the reaction of polypropylene oxide polyol and polyisocyanate, and then reacted with Y-aminopropyl trimethoxysilane to obtain silyl-terminated polymer.
2. Polymers with silyl end groups were synthesized by addition reaction of allyloxy-terminated polypropylene oxide and ryptoalkoxysilane.
3. The addition reaction of allyloxy-terminated polypropylene oxide and alkyloxysilane in the presence of platinum catalyst resulted in the formation of silyl-terminated polymers.
4. Polypropylene oxide with epoxy group at the end reacts with amino compounds and aminoalkoxysilane in the presence of primary alcohols to obtain silyl-terminated polymers.
MS gum is a mixture. In addition to the modified polysiloxane as the basic polymer, fillers, additives, catalysts, colour paste, etc. should be added to make the formulation. Moreover, the composition of the formula varies according to its use.