Physical and chemical properties of epoxy resin
Release time:
2023-02-14
Material property
Epoxy resins have a secondary hydroxyl group and an epoxy group, and the secondary hydroxyl group can react with isocyanate. Epoxy resin as a polyol is directly added into the component containing the hydroxyl group of polyurethane adhesive. In this method, only the hydroxyl group takes part in the reaction, while the epoxy group does not react.
The carboxyl group of acid resin is used to make the epoxy ring opening, and then react with the isocyanate in the polyurethane adhesive. The epoxy resin can also be dissolved in ethyl acetate, adding phosphoric acid for heating reaction, and the admixture can be added to the polyurethane adhesive, which can improve the initial adhesion, heat resistance and hydrolysis stability of the adhesive. Polyols can also be formed by the reaction of alcoholamine or amine, and the presence of tertiary nitrogen atoms in the admixture can accelerate the NCO reaction.
The use of epoxy resin as polyhydroxyl component combines the advantages of polyurethane and epoxy resin and has better bonding strength and chemical resistance. EP-12, EP-13, EP-16, EP-20 and other epoxy resins are generally used in the manufacture of polyurethane adhesives.
Modification method
1. Select curing agent;
2. Add reactive diluent;
3. Add filler;
4. Add special thermosetting or thermoplastic resins;
5. Improve the epoxy resin itself.
Prev
Prev
Basic classification of epoxy resins
2023-02-14