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

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 The TGPh-based formulations exhibited lower reaction temperatures and narrower reaction intervals. Additionally, these systems showed higher tan δ values (189°C–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 (1.3–1.4 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 h for TGPh-based resins and 4.5 h 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.

10 years of frontiers in carbon-based materials: carbon, the “newest and oldest” material. The story so far

“…Among those investigated in that work, the most promising film had a tensile strength of 166 MPa, a fracture strain of 2.4%, and Young's modulus of 7.6 GPa. Dinu et al (2023) developed thermosets that were environmentally friendly and chemically recyclable using the triglycidyl ether of phloroglucinol (TGPh), a renewable-based monomer, or a commercial non-toxic tris(4-hydroxyphenyl) methane triglycidyl ether (THPMTGE) monomer. The physicochemical and thermomechanical properties of the developed resins were characterised by means of differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), hardness tests, tensile testing, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), among other techniques.…”

“…In this section, polymer-based materials such as thermosets are also included. Dinu et al (2023) reported the outstanding preparation of sustainable and recyclable thermosets which were synthesized by crosslinking triglycidyl ether of phloroglucinol (TGPh) with either hexahydro-4-methylphthalic anhydride (HMPA) or methyl nadic anhydride (MNA).…”

An algae-derived partially renewable epoxy resin formulation for glass fibre-reinforced sustainable polymer composites

“…23,24 Resin formulations using epoxidized phloroglucinol (phloroglucinol trisepoxy, PHTE) in the presence of anhydride hardeners have been reported by Mija and colleagues, whereas they further pursued carbon fibre-reinforced polymer composite formation using a PHTE-based resin with ester bonds exhibiting recyclability (the matrix dissolved in ethylene glycol solution at 170 °C after 2.5 h). 25,26…”