Epoxy curing agent and its properties:
All grades of epoxy resins, thermoplastic polymers are linear structure in itself, it must undergo a curing agent to become insoluble solid body type lattice structure of giant molecular polymers. This process is called curing or hardening, curing process. Where epoxy and epoxy radicals and hydroxyl groups and substance called hardener or hardener for epoxy resin curing.
Many kinds of curing agents for epoxy resins, currently there are more than 10 kinds of commonly used. Including multiple amine, acid anhydride and other polymers, such as polyamide resins, phenolic resins and Thiokol.
More than more than 2.1 amine curing agent: commonly used multiple amine has two amine, has diluted a number of m-Phenylenediamine and dopamine.
Diamine, also known as butadiene diamine (or two-amino-n-hexane, ethylene diamine), molecular weight is 60.1, with four active hydrogen, every molecule has two amine reacts with four epoxy, is a colorless liquid, exposure to take white smoke in the air, a pungent ammonia smell. Dermatitis in long term contact with the skin, inhaled respiratory stimulation respiratory mucosa. Therefore, when indoor ventilation, wear masks and try to make it less contact with the skin.
Diamine reaction is exothermic reaction with epoxy resin, gel resins should be regulating temperature is less than 40 ℃. Has II amine of dosage General for epoxy resin dosage of tune, as dosage had big, in adjustable rubber process in the on curing or said operation not completed rubber has half curing has, caused waste, both makes barely bonded has, curing Hou of quality also bad, easy produced many pine hole-like is crisp of organization, as dosage had small, curing speed slow or reaction not completely, strength also low.
Curing conditions: at room temperature (20 ℃), 24 hours to fully cure.
In the case of a conditional, it is best to heat curing, fast curing, high strength. Curable 120 ℃ for 3 hours, 150 ° c for 2 hours to cure, slow parts to ambient temperature may be used.