Advanced materials from corn: isosorbide-based epoxy resins

Abstract

Water soluble epoxy resins were prepared from diglycidyl ethers of isosorbide (DGEI) and isosorbide diamine (ISODA). We investigated the effect of synthesis methods on the structure of DGEI and ISODA and their influence on properties of cured resins, and compared with bisphenol A commercial epoxy resins (DGEBA). DGEI and DGEBA were cured with diethylene triamine (DETA) and ISODA to give optically clear yellow to brown epoxy resins of different degrees of crosslinking. All systems containing isosorbide either on the epoxy or amine side were faster than the standard petrochemical epoxy resin (DGEBA/DETA). The glass transition of isosorbide-based resins was about 60 °C lower than those of DGEBA/DETA. The effect of DGEI molecular weight on properties of cured resins was tested. Isosorbide-based epoxy resins displayed equal or better tensile and impact strength than commercial epoxy resins and are a viable replacement for DGEBA resins but extensive research is necessary to improve hydrolytic stability.