Rapid epoxy curing agent at room temperature and its application in the preparation of epoxy dry-hanging adhesive

Abstract

The invention discloses a room temperature fast epoxy curing agent and its application in preparing epoxy dry-hanging adhesive. Its raw materials include 80-120 parts by weight of pentaerythritol, 250-350 parts of thioglycolic acid, 50-140 parts of epoxy resin, 0.10-0.20 parts of diisocyanate and 5.5-44 parts of imidazole. In the method, pentaerythritol and mercaptoacetic acid are mixed, and after esterification reaction, distillation under reduced pressure is performed, and diisocyanate is added thereto, and epoxy resin is added to carry out chain extension reaction to obtain a room temperature fast curing agent. Compared with the large amount of room temperature fast curing agent used in the existing room temperature fast drying adhesive, the high ratio room temperature fast curing agent accounts for a small proportion in the epoxy dry hanging adhesive, and has obvious advantages in cost. Compared with hanging glue, the gel time has been significantly improved, and the mechanical properties have not decreased, and the cost increase is very small.

Description

technical field [0001] The invention relates to the technical field of epoxy curing agents and epoxy dry-hanging adhesives, in particular to a room-temperature rapid epoxy curing agent and its application in preparing epoxy dry-hanging adhesives. Background technique [0002] Epoxy resin curing agent is an additive that chemically reacts with epoxy resin to form a network-like three-dimensional polymer, envelops the composite material in the network, and makes the linear resin into a tough solid body, including many types. [0003] According to the curing temperature, epoxy curing agents can be divided into four categories: [0004] a. The curing temperature of the low-temperature curing agent is below room temperature (25°C); there are few types of curing agents that belong to the low-temperature curing type, such as polythiol type and polyisocyanate type; T-31 modified amine, YH- 82 modified amines can be cured below 0°C. [0005] b. The curing temperature of the room t...

AI Technical Summary

Problems solved by technology

However, the epoxy dry-hanging glue cured at room temperature has defects such as slow curing speed, incomplete curing, and insufficient strength when the ambient temperature is low.

However, using traditional low-temperature curing agents to cure epoxy structural adhesives at room temperature will have disadvantages such as high price, unacceptable ordinary construction, and insufficient strength. Using T31 and YH-82 modified amine curing agents will have relatively slow curing speeds. Slow, too high rigidity, too low toughness and other shortcomings, so that low-temperature curing agent is rarely used in epoxy structural adhesives

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