Synthesis and characterization of soybean epoxy resin with phenoxy and gly cidyl ether groupsAuthor(s): M.Sarojadevi, S.Rakesh, V.Thulasiraman
Newsoybean epoxy resin with phenoxy and glycidyl ether groups (SEPG) was prepared fromthe renewable source soybean oil. The SEPG was characterized by spectral and titrationmethods. The prepared SEPGwas blended with commercial epoxy resin in different ratios and cured at 850C for 3h, 1500C for 1h and post cured at 2250C for 2h using m-phenylene diamine (MPDA) as curing agent. The epoxy/SEPG/MPDAwith different compositions cured in the temperature range of 120 -1530C as revealed by DSC studies. Composite laminateswere fabricated using epoxy/SEPG/MPDAglass fibre at different compositions. The tensile strength(280-310MPa), tensilemodulus(3.1-3.4GPa), flexural strength(365-395MPa), flexuralmodulus( 7.3-8.0 GPa) and impact strength (33.9-36.1J/cm) were studied. The interlaminar fracture toughness(GIC) values increased from 0.6953 KJ/m2 for neat epoxy resin to 0.8423KJ/m2 for themodified epoxy resin in the 20% SEPG. Thermo gravimetric studies reveal that thermal stability of the neat epoxy resin was decreased by incorporation of SEPG.