Abstract:
Diglycidyl ether of bisphenol-A (DGEBA), having number average molecular weight (Mn) 375, was modified by incorporating
the hydroxyl terminated polybutadiene (HTPB) based prepolymer using isophorone diisocyanate as a coupling
agent. To increase the compatibility between the epoxy resin and HTPB part, polar groups were introduced in the
later to achieve physical and chemical interactions between the two phases. The finally modified DGEBA system was
cured with amine based hardener. FTIR and 1
H-NMR were used to monitor the whole modification procedure. The
rubber particles size and distribution was monitored as a function of HTPB contents in the resin system using scanning
electron microscopy (SEM). The mechanical, thermal and thermo-mechanical properties have shown that the tensile
strength, toughness, ductility and impact strength of the modified cured system have been successfully increased at
some optimum HTPB contents without affecting the inherent thermal and thermo-mechanical stability associated with
DGEBA resin system. Some of the mechanical properties like flexural modulus, tensile modulus and compressive
strength decreased with increasing rubber contents.
