Curing Kinetics and Properties of Epoxy Resin with 1, 4-bis (2, 4-diaminophenoxy)benzene

Abstract

A multifunctional amine, 1,4-bis(2,4-diaminophenoxy)benzene (14BDAPOB), was prepared and used as a novel hardener for novolac epoxy resin (ER). The structure of 14BDAPOB was characterized with Fourier transform infrared (FT-IR) spectroscopy and differential scanning calorimetry (DSC). The curing kinetics of the novolac epoxy resin/1,4-bis(2,4-diaminophenoxy)benzene (ER/14BDAPOB) system was studied by means of non-isothermal DSC experiments at five heating rates and determined by the Kissinger, Ozawa and Crane methods. The results showed that the activation energy E _a of the ER/14BDAPOB (74.56 kJ/mol) system was higher than that of the epoxy resin/LCA-30 (ER/LCA-30, 68.85 kJ/mol), where LCA-30 is a commercial modified diamine. The reaction order, frequency factor and the reaction rate constant at peak temperature of the two systems were calculated. The initial decomposition temperatures (T _onset) were 398.8 °C (ER/14BDAPOB) and 334.3 °C(ER/LCA-30). The tensile shear strengths were 21.63 MPa (ER/14BDAPOB) and 21.28 MPa (ER/LCA-30). The results showed that the two cured systems exhibited good thermal and mechanical properties.

Keywords

epoxy resin / reaction kinetics / hardener / thermal properties / mechanical properties