Curing Mechanism of Epoxy Resin
The principle of epoxy resin hardening reaction is not perfect at present. According to the different hardeners used, it is generally believed that epoxy resin can be thermosetting products through four ways of reaction.
(1) Open-ring connection between epoxy groups;
(2) The epoxy group reacts with the hardener with the active hydrogen functional group and crosslinks.
(3) The epoxy group is crosslinked by the reaction of aromatic or fatty hydroxyl groups in the hardener.
(4) Crosslinking of epoxy group or hydroxyl group with group of hardener
Different kinds of hardeners play different roles in the hardening process. Some hardeners, such as amines, alcohols and phenols, which have single reaction groups, do not participate in the hardening process and only play a catalytic role. The hardener participates in the reaction between macromolecules during the hardening process and forms part of the hardening resin, such as polyamines, polyols, polyanhydrides and other compounds containing multiple reaction groups.
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