Development Of Bio-Based Thermosetting Resins

Thermoset polymers are widely used polymers in the world, but Increase in global plastic pollution and lack of fossil fuel stimulates intense research towards environmentally sustainable materials. Bio-based unsaturated polyesters (UPs) would be an excellent solution to replace oil-based synthetic polyesters. Most of the unsaturated polyesters have been synthesised by ring opening polymerisation (ROP) of cyclic esters or lactides. In this study, different resins were developed using different initiators such as isosorbide (IS),1,4 butanediol (BD), and cis-2 butene 1,4 diol (C2BD) with monomers like lactide (L) and alpha angelica lactone (AAL) through the ring opening polymerisation process. The produced resins were further characterised by using Fourier Transform Infrared Spectroscopy (FTIR),Nuclear Magnetic Resonance (NMR), Thermogravimetric Analysis (TGA), Differential Scanning Calorimeter (DSC), and Dynamic Mechanical Analysis (DMA). Synthesis of resin with lactone monomer was not successful while with lactide monomer it was successful. IS-based resin showed better thermal properties compared to other obtained resins. Tg value of IS containing resin was 63°C, thermal stability up to 235°C and Storage modulus about 3841 MPa. These values are comparable with other bio-based resins produced using the same monomer.