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Carbon fiber reinforced polymers (CFRPs, or composites) are increasingly replacing traditional manufacturing materials used in the automobile, aerospace, and energy sectors. With this shift, it is vital to develop end-of-life processes for CFRPs that retain the value of both the carbon fibers and the polymer matrix. Here we demonstrate a strategy to upcycle pre- and post-con- sumer polystyrene-containing CFRPs, crosslinked with unsaturated polyesters or vinyl esters, to benzoic acid. The thermoset matrix is upgraded via biocatalysis utilizing an engineered strain of the filamentous fungus Aspergillus nidulans, which gives access to valuable secondary metabolites in high yields, exemplified here by (2Z,4Z,6E)-octa-2,4,6-trienoic acid. Reactions are engineered to preserve the carbon fibers, with much of their sizing, so that the isolated carbon fiber plies are manufactured into new composite coupons that exhibit mechanical properties comparable to virgin manufacturing substrates. In sum, this represents the first system to reclaim high value from both the fiber fabric and polymer matrix of a CFRP.
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SELECTIVE CLEAVAGE OF AMINE-LINKED EPOXY COMPOSITE MATRICES BY OXYGEN
This presentation will describe conditions for the use of oxygen as a reagent for the selective cleavage of thermoset composites. Carbon fiber-reinforced polymer (CFRP) composites have a prominent role in aviation, sporting goods, marine, and other manufacturing sectors and are accumulating en masse as waste, both at end-of-life and as manufacturing defects. We have recently introduced a method to use oxygen itself along with an appropriate catalyst selectively to disassemble such fully-cured composite wastes to recover both ordered carbon fiber sheets and organic materials suitable for re-manufacturing of second-life resin systems.
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- PAR ID:
- 10434771
- Date Published:
- Journal Name:
- SAMPE 2023
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.33599/nasampe/s.23.0206
