Synthesis and Characterization of Fully Biobased Epoxy Elastomers Prepared from Different Plant Oils

A simple and facile method to prepare fully biobasedepoxy elastomerswith a high toughness is still a big challenge. In this study, a seriesof fully biobased epoxy elastomers were prepared by curing differentepoxidized plant oils with a biobased diamine Priamine 1074. The curingbehavior and catalytic process of these biobased epoxy elastomerswas systematically studied. The effects of the different numbers ofepoxy groups of these epoxidized plant oils and the equivalent ratiosof amine and epoxy groups on the performance (thermal stability, mechanicalproperties, etc.) of the epoxy elastomers were studied and discussed.Furthermore, the potential of these epoxy elastomers as wearable flexiblesensors was explored. It is found that ring opening polymerizationand ester aminolysis reaction between amine groups of diamines andester groups of epoxidized plant oils simultaneously occurred duringthe curing process. The properties, (thermal stability, thermophysicaland mechanical properties, etc.) of these epoxidized plant oils couldbe tailored by selecting epoxidized plant oils with different numbersof epoxy groups and controlling equivalent ratios of amine and epoxygroups. The maximum elongation at break of the epoxy elastomers couldreach up to 338.58%. After spray coating with Ag nanowires, theseepoxy resins demonstrated excellent detection of motion signals atvarious joints and other regions of the body. Combining with the resultsof not being cytotoxic to Caco-2 cells, the epoxy elastomers reportedin this study are expected to be applied in the field of wearableflexible sensors. Fully biobasedepoxy elastomers were prepared from differentplant oils for potential application as flexible strain sensors.