Title: Renewable and Recyclable Thermosets for Continuous Carbon Fiber Recovery

Authors: Jaclyn A. McLaughlin, Giuseppe R. Palmese

DOI: 10.33599/nasampe/s.24.0031

Abstract: Carbon fiber reinforced polymers (CFRPs) combine continuous carbon fiber reinforcements within a thermoset matrix to create high-performance engineering materials. As the demand for CFRPs continues to increase, it is important to consider the lifecycle of their constituent materials. The irreversible nature of conventional thermoset matrices has forced the composites industry to operate on a linear economy wherein no material is reused in subsequent production streams. In this work, bio-based methacrylate crosslinkers containing a pH-sensitive chemical linkage are used to prepare hydrolysable thermosets that will enable the recovery of continuous carbon fibers from CFRPs at end-of-life. Formation of the polymer network by chain-growth and step-growth polymerization strategies are studied to evaluate the influence of network structure on the properties and hydrolysis of resultant thermosets. Thermoset samples cured by free radical chain-growth exhibited higher levels of monomer conversion and thermomechanical properties than polymers formed by the step-growth method. However, the uniform structure of polymer networks generated from step-growth polymerization can enable recovery of precursor materials upon hydrolysis. Both sets of samples readily hydrolyze when placed in 1 M HCl solution, promising the recovery of continuous carbon fibers from CFRPs and facilitation of a circular economy set up for composites.

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Conference: SAMPE 2024

Publication Date: 2024/05/20

SKU: TP24-0000000031

Pages: 14

Price: $28.00