Growing Carbon Nanotubes In Situ Surrounding Carbon Fiber Surface via Chemical Vapor Deposition to Reinforce Flexural Strength of Carbon Fiber Composites

Guangming Yang; Fei Cheng; Shihao Zuo; Jinheng Zhang; Yang Xu; Yunsen Hu; Xiaozhi Hu

doi:10.3390/polym15102309

Growing Carbon Nanotubes In Situ Surrounding Carbon Fiber Surface via Chemical Vapor Deposition to Reinforce Flexural Strength of Carbon Fiber Composites

Polymers (Basel). 2023 May 15;15(10):2309. doi: 10.3390/polym15102309.

Authors

Guangming Yang¹, Fei Cheng^{1

2}, Shihao Zuo¹, Jinheng Zhang¹, Yang Xu¹, Yunsen Hu³, Xiaozhi Hu⁴

Affiliations

¹ School of Materials and Chemistry, Southwest University of Science and Technology, Mianyang 621010, China.
² Engineering Research Center of Biomass Materials, Ministry of Education, Southwest University of Science and Technology, Mianyang 621010, China.
³ School of Mechanical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, China.
⁴ Department of Mechanical Engineering, University of Western Australia, Perth, WA 6009, Australia.

Abstract

This study employed novel joint treatments to strengthen the carbon fiber reinforced polymer (CFRP) composites. Vertically aligned carbon nanotubes (VACNTs) were prepared in situ on the catalyst-treated CF surface via the chemical vapor deposition (CVD) method, intertwining into three-dimensional fiber-nets and fully surrounding CF to form an integrated structure. The resin pre-coating (RPC) technique was further used to guide diluted epoxy resin (without hardener) to flow into nanoscale and submicron spaces to eliminate void defects at the root of VACNTs. Three-point bending testing results showed the "growing CNTs and RPC"-treated CFRP composites yielded the best flexural strength, a 27.1% improvement over the specimens without treatment, while the failure modes indicated that the original delamination failure was changed into "flexural failure" with through-the-thickness crack propagation. In brief, growing VACNTs and RPC on the CF surface enabled toughening of the epoxy adhesive layer, reducing potential void defects and constructing the integrated quasi-Z-directional fiber bridging at the CF/epoxy interface for stronger CFRP composites. Therefore, the joint treatments of growing VACNTs in situ via the CVD method and RPC technique are very effective and have great potential in manufacturing high-strength CFRP composites for aerospace applications.

Keywords: carbon fiber reinforced polymer (CFRP); chemical vapor deposition (CVD); integrated fiber bridging; resin pre-coating (RPC); vertically aligned carbon nanotubes (VACNTs).

Grants and funding

This work was financially supported by the National Natural Science Foundations of China (Grant No. 52102115), the Natural Science Foundations of Sichuan Province (Grant No. 2023NSFSC0961) and the Overseas High-end Talent Introduction Project of Sichuan Province (Grant No. 2023JDGD0013). The APC was funded by the National Natural Science Foundations of China (Grant No. 52102115).