Depositing carbon nanotubes (CNTs) into carbon fiber reinforced polymer composites (CFRPs) is challenging because of the need for complicated lab-scale processes and toxic chemical dispersants that makes conventional means of processing less compatible with existing industrial procedures for large-scale applications. In this work, a scalable supercritical CO2-assisted atomization technique is used to effectively deposit hybrid CNTs in CFRPs allowing them to boost their functionality and tailor the microstructure. Cellulose nanocrystals (CNCs) are utilized to create hybrid nanostructures with CNTs (CNC bonded CNT) that enables stabilization of CNTs in nontoxic media, i.e., water, and this promotes the scalability of the process. According to Zeta potential values, CNCs successfully stabilize CNTs in water suspension. Scanning electron microscopy (SEM) micrographs show hybrid CNC bonded CNTs are homogeneously dispersed on the carbon fiber surface. According to the in-situ bending test under the optical microscope, crack propagation is hindered by engineered hybrid CNT nanostructures in the modified CFRP whereas neat CFRP exhibits low crack growth resistance due to the uninterrupted crack propagation in the continuous epoxy matrix. Our results imply that this strategy probes the importance of new controlled manufacturing of hybrid nanostructures through evaporation‑induced self‑assembly of nanocolloidal droplets, and allows for tailoring of the desired properties of nanostructured composites.
Interfacial Properties of Hybrid Cellulose Nanocrystal/Carbonaceous Nanomaterial Composites
Cellulose nanocrystal (CNCs) assisted carbon nanotubes (CNTs) and graphene nanoplatelets (GnP) were used to modify the interfacial region of carbon fiber (CF) and polymer matrix to strengthen the properties of carbon fiber-reinforced polymer (CFRP). Before transferring CNC-CNTs and CNC-GnPs on the CF surface by an immersion coating method, the nanomaterials were dispersed in DI water homogeneously by using probe sonication technique without additives. The results showed that the addition of CNC-CNT and CNC-GnP adjusted the interfacial chemistry of CFRP with the formation of polar groups. Furthermore, according to the single fiber fragmentation test (SFFT), the interfacial shear strength (IFSS) of CNC-GnP 6:1 and CNC-CNT 10:1 added CFRP increased to 55 MPa and 64 MPa due to modified interfacial chemistry by the incorporation of the nanomaterials. This processing technique also resulted in improvement in interlaminar shear strength (ILSS) in CFRPs from 35 MPa (neat composite) to 45 (CNC-GnP 6:1) MPa and 52 MPa (CNC-CNT 10:1).
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- Award ID(s):
- 1930277
- NSF-PAR ID:
- 10378814
- Date Published:
- Journal Name:
- Proceedings of the American Society for Composites—Thirty-Sixth Technical Conference on Composite Materials
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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