synthesis of modified epoxy resin-acrylate (EAM): EAM resin is a modified epoxy resin-acrylate obtained from E-51 epoxy resin, methacrylic acid and maleic anhydride.
In a three-mouth bottle equipped with a stirrer, a reflux condenser, and a thermometer, add epoxy resin, methacrylic acid, maleic anhydride, polymerization inhibitor, catalyst, etc., under the protection of nitrogen, react at 110-120 ℃ The conversion rate of unsaturated acid is ≥ 95%, stop the reaction, and add diluent after cooling.
EBMA resin (epoxy dimethacrylate) is the product of the reaction of epoxy resin and methacrylic acid.
PU-EBAM resin: EBAM resin is reacted with HD (hexamethylene diisocyanate), polymerization inhibitor, catalyst, etc. according to a certain proportion at a certain temperature until the-NCO group basically disappears.
PU-EAM resin: EAM resin is reacted with HDI, polymerization inhibitor, catalyst, etc. at a certain temperature according to a certain proportion until the-NCO group basically disappears.
Preparation of Orthodontic Adhesive: Orthodontic Adhesive is composed of A and B two-component liquid primer and A and B two-component adhesive paste. The matrix resin PU-EAM, diluent, EDMA, inhibitor, 2, 6-di-tert-butyl p-toluidine and dihydroxyethyl p-toluidine accelerator are added according to component A, benzoyl peroxide initiator is added to component B, and silylated silica is added to the adhesive paste and mixed evenly.