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Title: Composite Recycling with Biocatalytic Thermoset Reforming
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.  more » « less
Award ID(s):
2227649 2134658
PAR ID:
10560383
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
Journal of the American Chemical Society
Volume:
146
Issue:
44
ISSN:
0002-7863
Page Range / eLocation ID:
30004 to 30008
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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