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Updated: May 26, 2025

Designed for Molecular Recycling: A Lignin-Derived Semi-aromatic Biobased Polymer
Published on: November 30, 2020
Rapid Microwave-Assisted Chemical Recycling of Poly(p-Phenylene Terephthalamide)
Joël Benninga1,2, Bert Gebben3, Rudy Folkersma2
1Macromolecular Chemistry and New Polymeric Materials, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 3, 9747 AG Groningen, The Netherlands.
Abstract:
Back-to-monomer chemical recycling of polymers is crucial in achieving a circular plastics economy. Herein, we report the rapid microwave-assisted depolymerization of poly(p-phenylene terephthalamide) (PPTA), also known as Twaron or Kevlar. The alkaline hydrolysis of PPTA was conducted in a microwave reactor at temperatures ranging from 240 to 260 °C with reaction times of 1-15 min. The highest conversion (96%) was found after 15 min at 260 °C. The resulting monomers terephthalic acid and p-phenylenediamine were successfully purified (>99% purity) in good yields using extraction and precipitation methods. This work presents the fastest depolymerization of PPTA to date under relatively mild conditions, thereby encouraging a circular value chain for PPTA.
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