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This paper utilizes a periodic unit cell modeling technique combined with finite element analysis (FEA) to predict and understand the mechanical behaviors of a nanotechnology-enhanced carbon fiber reinforced polymers (CFRPs) composite. This research specifically focuses on the study of novel Z-threaded CFRPs (ZT-CFRPs) that are reinforced not only by unidirectional carbon fibers but also with numerous carbon nanofibers (CNFs) threading through the CFRP laminate in the z-direction (i.e., through-thickness direction). The complex multi-scaled orthogonally-structured carbon reinforced polymer composite is modeled starting from a periodic unit cell, which is the smallest periodic building-block representation of the material. The ZT-CFRP unit cell includes three major components, i.e., carbon fibers, polymer matrix, and carbon nanofiber Z-threads. To compare the mechanical behavior of ZT-CFRPs against unmodified, control CFRPs, an additional unit cell without CNF reinforcement was also created and analyzed. The unit cells were then meshed into finite element models and subjected to different loading conditions to predict the interaction among all their components. The elastic moduli of both unit-cells in the z-direction were calculated from the FEA data. By assuming the CNFs have the same mechanical properties of T-300 carbon fiber, the numerical modeling showed that the ZT-CFRPs exhibited a 14% improvement in z-directional elastic modulus due to the inclusion of 1 wt% CNF z-threads, indicating that ZT-CFRPs are stiffer compared to control CFRPs consisting of T-300 carbon fibers and epoxy.
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This content will become publicly available on November 6, 2025
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.
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- PAR ID:
- 10560383
- 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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