237: Designing High-Performance Vitrimers from Reutilized Plastic Waste and Novel Biobased Building block

DESIGNING CIRCULAR HIGH-PERFORMACE CONDENSATION POLYMERS FROM THE REUTILIZATION OF PLASTIC WASTE AND NOVEL BIOBASED BUILDING BLOCKS

Abhijith Krishna, Louis PITET

Advanced Functional Polymers (AFP) Laboratory, Institute for Materials
Research (imo-imomec), Hasselt University, Martelarenlaan 42, 3500 Hasselt, Belgium.

Vitrimers represent an emerging class of polymeric materials that combine the reprocessability and repairability of thermoplastics with the mechanical robustness and chemical resistance of thermosets. This project explores a sustainable approach to vitrimer synthesis by upcycling post-consumer polyethylene terephthalate (PET) waste into high-performance dynamic networks. Central to this strategy is the use of hydrolyzed polyfarnesene (HyPF), a bio-based polymer synthesized via green methodologies from polyfarnesene, a renewable terpene-derived hydrocarbon. Two synthetic pathways were investigated to incorporate HyPF into vitrimer networks: (i) a polycondensation approach wherein chemically modified PET oligomers are crosslinked with HyPF, and (ii) a one-pot method involving in situ depolymerization of PET, followed by direct reaction with HyPF to generate a vitrimeric intermediate, which can be isolated by precipitation and subsequently processed via heat pressing to form the final vitrimer material.

Catalysis plays a crucial role in both synthetic pathways. In the polycondensation approach, zinc acetate [Zn(OAc)₂] and Titanium tetrabutoxide (TBT) were employed as catalysts to facilitate the transesterification and condensation reactions. For the one-pot synthesis, 1-ethyl-3-methylimidazolium chloride (EMIC), an ionic liquid known for its catalytic efficiency in PET depolymerization, was utilized to promote the simultaneous breakdown and functionalization of PET in the presence of HyPF The resulting vitrimers were thoroughly characterized to evaluate their thermal properties, rheological behavior, and reprocessability. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) confirmed the thermal stability of the networks, while rheological studies demonstrated their dynamic viscoelastic behavior, indicative of vitrimeric flow at elevated temperatures. Reprocessing trials confirmed the materials' capacity for reshaping and healing without significant degradation in properties.

This work demonstrates a circular approach to polymer design by integrating post-consumer plastic waste and bio-based feedstocks into a new class of dynamic polymer networks. The dual emphasis on sustainability and material performance highlights the potential of these vitrimers in addressing long-term challenges related to plastic waste and resource conservation in polymer science.

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