Sustainable Bio-Based Epoxy Technology Progress

Sustainable bio-based epoxy technology is developed by using bio-based epoxy materials instead of conventional fossil-derived ones. Significant progress in new bio-based epoxy material development on bio-based epoxy resins, curing agents, and additives, as well as bio-based epoxy formulated products, has been achieved recently not only in fundamental academic studies but also in industrial product development. There are mainly two types of bio-based epoxy resins: conventional epoxy resins and novel epoxy resins, depending on the epoxy resin building-block type used. Bio-based conventional epoxy resins are prepared by using the bio-based epichlorohydrin to replace conventional fossil-based epichlorohydrin. Bio-based novel epoxy resins are usually prepared from epoxidation of renewable precursors such as unsaturated vegetable oils, saccharides, tannins, cardanols, terpenes, rosins, and lignin. Typical bio-based curing agents are bio-based polyamines, polyamides, amidoamines, and cardanol-based phenalkamine-type curing agents. Cardanol is a typical bio-based reactive additive available commercially. Certain types of partially bio-based formulated epoxy products have been developed and supplied for use in bonding, coating, casting, composite, and laminating applications.