Chemically Recyclable Polyester Thermosets from Activated Adipic Acid and Renewable Polyols.

Area of Science:

• Polymer Chemistry
• Materials Science
• Sustainable Chemistry

Background:

• Developing sustainable and recyclable polymers is crucial for reducing environmental impact.
• Crosslinked polyesters offer desirable material properties but often lack efficient recycling pathways.

Purpose of the Study:

• To develop a method for producing chemically recyclable crosslinked polyesters using renewable resources.
• To investigate the synthesis and characterization of novel thermosets derived from glycerol and sorbitol.

Main Methods:

• A three-step synthesis involving polyanhydride formation from adipic acid, reaction with renewable polyols (glycerol, sorbitol), and thermoset molding.
• Characterization using tensile tests, DMA, solid-state NMR, TGA, DSC, and FT-IR spectroscopy.

Main Results:

• Successfully synthesized eight different thermosets with varying reagent ratios.
• Achieved high tensile strength up to 18 MPa, significantly exceeding similar polymers, particularly with a 1:1 wt% sorbitol to crosslinking mixture (CLM) ratio.
• Demonstrated quantitative recovery of monomeric units via methanolysis, confirming chemical recyclability.

Conclusions:

• The developed method enables the production of high-performance, chemically recyclable crosslinked polyesters from renewable feedstocks.
• The process is solvent- and additive-free, enhancing its sustainability.
• The recyclability via methanolysis offers a viable route for circular polymer economy.