Fully bio-based reprocessable thermosetting resins based on epoxidized vegetable oils cured with itaconic acid

Nowadays, biomass-derived monomers production and thermosets' recyclability are the two main efforts in the development of sustainable thermosetting epoxy resins to replace fossil derivatives and mitigate landfill build-up and ecological impact. Here, we propose a simple step and benign synthesis strategy by using the itaconic acid (IA) and two epoxidized vegetable oils (EVOs), linseed and soybean, in order to obtain fully bio-based materials with high carbon bio-content. The reactivity of these formulations, together with the properties of obtained thermosets were investigated and compared with that of DGEBA/IA homologous system. The EVOs/IA reactive mixtures show high reactivity, tested by differential scanning calorimetry (DSC) and Fourier-transformed infrared spectroscopy (FT-IR) while the obtained resins display good mechanical properties, high thermal stability as well as resistance to solvents. Due to the transesterification reaction in the polyester-based networks, recycling abilities tested both mechanically and chemically were proven. The fully reprocessed bio-based thermosets displayed almost unchanged thermomechanical properties and chemical structure combined with a simple and green chemical processing.

Automated summary

In this study, a simple and benign synthesis strategy was proposed to produce fully bio-based materials using itaconic acid and two epoxidized vegetable oils. The reactive mixtures showed high reactivity and the obtained resins exhibited good mechanical properties, high thermal stability, and solvent resistance. The materials also demonstrated recycling capability through transesterification reaction.