Abstract
In this study, bi-, tri-, and tetra-functional epoxy systems were chosen to design network structures using hexahydrophthalic anhydride as curing agent and tris-(dimethylaminomethyl) phenol as accelerant with bifunctional 1,4-butanediol diglycidyl ether as the flexible reactive diluents to further adjust the network structure. The cross-link density and activation energy (Ea) of glass transition were calculated by dynamic mechanical thermal analysis (DMTA) data. The packing of molecular chain and average distance between molecular chains were analyzed by DMTA and X-ray diffraction measurements, respectively. As a result, the loss modulus, glass transition temperature (Tg), cross-link density, average distance between molecular chains and Ea were found to be positively correlated with the degree of functionality. Meanwhile, the storage modulus of cured epoxy products at glass state was found to vary as follows: diglycidyl ether of bisphenol F (DGEBF) > tetraglycidyl diaminodiphenylmethane > triglycidyl-p-aminophenol (TGPAP). The loading of diluents decreased Tg and Ea and increased the storage modulus at glass state of DGEBF and TGPAP systems.
Get full access to this article
View all access options for this article.
