Curing Mechanism of Epoxide Resin

Abstract

Bisphenol type epoxide resin was cured with 4, 4'-diaminodiphenylmethane, and the process of curing was followed by observing the changes of, reactive groups, molecular weight distribu- tion, gel content, mechanical, dynamic mechanical and bonding properties of the system.
From these observations, process of curing of the system can be divided into three stages; namely ( 1 ) linear structure having molecular weight less than 1300, ( 2 ) non-crosslinked but branched structure having molecular weight less than 104 and ( 3 ) crosslinked structure.
In these three stages, good correlations were observed among mechanical, dynamic mechanical and bonding properties of the system. Chemical structures corresponding to these three stages were proposed and the correlations among above mentioned properties were also discussed.