AUTHOR=Dinu Roxana , Lafont Ugo , Damiano Olivier , Mija Alice 

TITLE=Sustainable and recyclable thermosets with performances for high technology sectors. An environmental friendly alternative to toxic derivatives

JOURNAL=Frontiers in Materials

VOLUME=Volume 10 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/materials/articles/10.3389/fmats.2023.1242507

DOI=10.3389/fmats.2023.1242507

ISSN=2296-8016

ABSTRACT=This study focuses on the development of environmentally friendly and chemically recyclable thermosets using or a renewable based monomer, the triglycidyl ether of phloroglucinol (TGPh), or a commercial non-toxic tris(4-hydroxyphenyl) methane triglycidyl ether (THPMTGE) monomer. The recyclable polyester thermosets were prepared by crosslinking the two monomers with hexahydro-4-methylphthalic anhydride (HMPA) or methyl nadic anhydride (MNA). The TGPh-based formulations exhibited lower reaction temperatures and narrower reaction intervals. Additionally, these systems showed higher tan δ values (189-199 °C), higher crosslinking densities (7.6-7.8 mmol∙cm-3) and compact networks, crucial for high-performance industries. Tensile tests demonstrated the remarkable mechanical properties of the thermosets, including high Young modulus (1.3 to 1.4 GPa), tensile stress (55-69 MPa), and an elongation at break around 3-8%. Moreover, the thermosets exhibited complete dissolution at a temperature of 170 °C, with depolymerization times of approximately 2.5 hours for TGPh-based resins and 4.5 hours for THPMTGE-based formulations. In conclusion, this study shows that sustainable and eco-friendly thermosets with excellent physico-chemical and thermo-mechanical properties, low hydrophilicity, and rapid dissolution capacity can be developed. These thermosets offer a viable alternative to non-recyclable and toxic resins in high-end industrial applications.