Low-viscosity, highly processable biobased thermoset polymers from phloroglucinol Tris-epoxy resin with a green eutectic hardener

This study presents the development of sustainable biobased thermosets, meeting high performance polymer properties. Two formulations were prepared through curing phloroglucinol tris epoxy resin (PHTE) with two bio-based eutectic hardeners (EH) synthesized from citric acid (CA) and diethyl malonate (DEM) at stoichiometric ratio of 0.5 and 1 ( R eutectic n DEM n CA = 0.5 , 1 ) . These formulations present advantages such as, high biobased content, low viscosity of few Pa.s and efficient thermal and mechanical properties. The glass transition temperatures ranging from 83 °C to 114 °C, Young's modulus of ≈ 2.8 GPa and a thermal stability ( T 10%) above 300 °C were obtained for the two biobased thermosets. Using eutectic hardeners to formulate high performance PHTE based thermosets has the potential to reduce the curing temperature, lowering the viscosity leading to easy processability contributing to increase the polymeric mixture homogeneity in high performance material manufacturing processes.