Simultaneously improving thermal conductivities and mechanical strength of carbon fibers/epoxy composites via CNT/copolymer hybrid interphase
*Correspondence to:
Junliang Zhang, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi’an 710072, Shaanxi, China.
E-mail: junliang.zhang@nwpu.edu.cn
Junwei Gu, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi’an 710072, Shaanxi, China. E-mail: gjw@nwpu.edu.cn
Junwei Gu, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi’an 710072, Shaanxi, China. E-mail: gjw@nwpu.edu.cn
Thermo-X. 2026;2:202618. 10.70401/tx.2026.0023
Received: May 11, 2026Accepted: July 01, 2026Published: July 01, 2026
This manuscript is made available in its unedited form to allow early access to the
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Abstract
Carbon fibers (CF)/epoxy composites are widely utilized in aerospace and transportation due to their light weight and high specific strength/modulus. However, poor interfacial binding between CF and the epoxy matrix leads to phonon scattering and inefficient load transfer, causing heat accumulation and reduced service life in high-power electronic systems. In this study, CF was coated with a styrene, benzocyclobutene, and methyl methacrylate units contained polymer layer mixed with carbon nanotubes (CNT) through impregnation and drying. The polymer layer was then thermally crosslinked to obtain the polymer and CNT coated CF (CF@(CNT/P)). CF@(CNT/P) was then applied as reinforced fibers and epoxy resin containing liquid crystal structure as matrix to prepare CF@(CNT/P)/epoxy composites. The π-π interactions and hydrogen bonds between CF and epoxy resin were enhanced by the benzene ring and ester groups in the polymer, thereby improving the interfacial binding between epoxy resin and CF. CF@(CNT/P)/epoxy composite showed enhanced load-bearing and thermal conduction performance. When the mass fractions of CNT and copolymer in CNT/P/dichloromethane (DCM) solution were 0.1 wt% and 0.03 wt%, respectively, the CF@(CNT/P) had the best interfacial binding to the epoxy resin. The interlaminar shear strength and flexural strength of the CF@(CNT/P)/epoxy composite increased from 23.7 and 252.5 MPa of CF/epoxy composite to 31.4 and 369.1 MPa, respectively. Meanwhile, the in-plane (λ∥) and through-plane (λ⊥) thermal conductivity were improved from 7.15 and 0.31 W/(m·K) of CF/epoxy composite to 10.08 and 0.58 W/(m·K), respectively. The CF@(CNT/P)/epoxy composite also demonstrated an electromagnetic interference shielding effectiveness of 38.6 dB which has broad application in high-power electronic information systems.
Keywords
Carbon fiber, epoxy resin, thermal conductivity, mechanical properties
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Lin Y, Zhang W, Guo H, Liu J, Zhang J, Guo Y, et al. Simultaneously improving thermal conductivities and mechanical strength of carbon fibers/epoxy composites via CNT/copolymer hybrid interphase. Thermo-X. 2026;2:202618. https://doi.org/10.70401/tx.2026.0023
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Lin Y, Zhang W, Guo H, Liu J, Zhang J, Guo Y, et al. Simultaneously improving thermal conductivities and mechanical strength of carbon fibers/epoxy composites via CNT/copolymer hybrid interphase. Thermo-X. 2026;2:202618. https://doi.org/10.70401/tx.2026.0023
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