Studies on the effect of
structure on cure and mechanical properties in tetrafunctional epoxy
resins
*K.S.Jagadeesh,
K.Shashikiran,
JSSATE,
C-20/1, Sector 62, Noida, U.P. India-201301.
*Address for
correspondence.
Abstract
Curing
studies of ortho-chloro
substituted epoxy resins based on TGDDM (Tetra-glycidyldiamino-diphenylmethane) with
different curing agents like o-DCDDM (3,3|dichloro-4,4|diamino-diphenylmethane), DDS (diamino-diphenylsulphone), PNA (hexaanilino-triphosphazene)
were carried out by Dynamic Differential Scanning Calorimetry
(DSC), rheology and by FTIR. The studies revealed
that the curing of the new resin systems was retarded when compared to the
extensively used TGOS30 [TGDDM
+DDS (30phr w/w for every 100phr resin)] resin system. The structure of the
amine and resin had a great influence on the reactivity and cure behavior. The
mechanical properties like tensile, flexural, Izod impact and HDT
were studied for the new formulations and compared with that of TGOS30. The results were interpreted in
terms of the extent of reaction and structure. The properties of the new
systems decreased due to the sterically hindered
amine. The impact strength of the new formulations was better than that of TGOS30 system.
Key words: Cure-kinetics, steric
hindrance, multifunctional epoxies, ortho
substitution, rheology