Synthesis and Characterization of a Novel Epoxy with Improved Processability

For purposes of developing a novel epoxy with low viscosity and high activity, N,N-diglycidyl-furfurlamine (DGFA) was successfully synthesized through a two-step reaction between 2-furfurylamine and epichlorohydrin involving ring-opening and ring-closure mechanisms. The product structure was verified by FTIR, 1H-NMR, 13C-NMR and elemental analysis, respectively. Its viscosity was found to be 0.02 Pa·s at 25oC. To understand its curing behavior, exothermic habit of the model mixture of DGFA and the curing agent methylhexahydrophthalic anhydride (MHHPA) at stoichiometric ratio of epoxy ring/anhydride of 1:0.8 was inspected with DSC. By changing the heating rates from 2.5 to 15oC/min, activation energy for consolidation of the resin was estimated to be 46.2 kJ/mol, which is much lower than the value involved in curing of diglycidyl ether of bisphenol A catalyzed by anhydride. Besides, thermal decomposition performance of cured version of the newly synthesized epoxy was also examined. The predominant pyrolysis took place at around 330-390oC as a result of chain scission of epoxy. The cured resin possesses comparable mechanical properties as conventional diglycidyl ether of bisphenol A. Its flexural strength and modulus are 111MPa and 3.6GPa, respectively. Evidently, the resultant epoxy is provided with balanced properties for practical applications.