In this study, a relatively low temperature synthesis technique; graphitic structure by design (GSD), was employed to grow multi‐walled carbon nanotubes (MWCNTs) over carbon fiber fabrics. The MWCNTs forests were grown into two different morphologies, uniform and patterned. Hybrid carbon fiber‐reinforced polymer composites (CFRPs) were fabricated based on the hybrid reinforcement. Double cantilever beam tests were performed to investigate the effect of the surface grown nano‐reinforcements on the Mode I interlaminar fracture toughness (GIc) of the hybrid CFRPs. Results revealed that the surface grown MWCNTs enhanced the GIcof the CFRPs by 22 and 32%, via uniform and checkerboard‐patterned growth morphologies, respectively. Fractography was also employed to reveal the MWCNTs’ role in interlaminar crack stoppage and deflection resulting in improving GIcof the hybrid CFRPs. POLYM. COMPOS., 40:E1470–E1478, 2019. © 2018 Society of Plastics Engineers
Effect of Nano-Reinforcement Topologies on the Viscoelastic Performance of Carbon Nanotube/Carbon Fiber Hybrid Composites
In this investigation, multi-walled carbon nanotubes (MWCNTs) were grown over carbon fiber fabrics via a relatively nondestructive synthesis technique. The MWCNTs patches were grown into three different topologies: uniform, fine patterned and coarse patterned. Hybrid carbon fiber-reinforced polymer composites (CFRPs) were fabricated based on the patterned reinforcements. Tensile tests, dynamic mechanical thermal analyses (DMTA) and flexure load relaxation tests were carried out to investigate the effect of the patterned nano-reinforcement on the static, dynamic, glass transition, and viscoelastic performance of the hybrid composites. Results revealed that the hybrid composite based on fine-patterned topology achieved better performance over all other configurations as it exhibited about 19% improvement in both the strength and modulus over the reference composite with no MWCNTs. Additionally, the increase in glass transition for this composite was as high as 13%. The damping parameter (tan δ) was improved by 46%. The stress relaxation results underlined the importance of patterned MWCNTs in minimizing the stress decay at elevated temperatures and loading conditions. Utilizing patterned MWCNTs topology significantly reduced the stress decay percentage at the thermomechanical conditions 60 MPa and 75 °C from 16.7% to 7.8%. These improvements are attributed to both the enhanced adhesion and large interface area by placing MWCNTs and by inducing an interlocking mechanism that allows the interaction of the three constituents in load transfer, crack deflection and hindering undesired viscoelastic deformations under different thermomechanical loadings.
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- Award ID(s):
- 2001038
- NSF-PAR ID:
- 10225003
- Date Published:
- Journal Name:
- Nanomaterials
- Volume:
- 10
- Issue:
- 6
- ISSN:
- 2079-4991
- Page Range / eLocation ID:
- 1213
- 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
- Journal Article:
- https://doi.org/10.3390/nano10061213
