Modified mechanical properties of carbon fiber/epoxy composite by silicone polymer

The application of carbon fiber (CF) in carbon fiber composites has faced limitations due to its surface chemical inertness. To overcome this challenge, this study draws inspiration from metal ion‐enhancing exquisite hierarchical and multiphase structures observed in biological materials. The research proposes a novel approach to enhance the interfacial bonding of CF/Epoxy (E‐51) composites by utilizing tannic acid (TA), carboxylated cellulose nanocrystals (CNCs), Fe3+ ions, and polyvinyl alcohol (PVA). This approach aims to create hydrogen bonding and metal synergistic networks on the surface of CFs through metal ion (Mn+) coordination cross‐linking synergistic (MCCS) interactions. Implementing MCCS strategy resulted in significant improvements in the mechanical properties of the hybrid reinforcements compared to untreated CF composites. The flexural strength, flexural modulus, interlaminar shear strength, and interfacial shear strength experienced respective increase of 50.9%, 72.8% 59.4%, and 61.9%. Moreover, the damping properties of the composites exhibited significant improvements. These positive outcomes can be attributed to the formation of chelation and dense hydrogen bonding networks between TA, Fe3+, CNC, and PVA. Furthermore, CNC and PVA formed cross‐linked nanolayers that effectively deflected cracks and facilitated high energy consumption at the interface. This proposed approach provides a sustainable, environmentally friendly, and efficient method for surface modification in the preparation of high‐performance fiber composites.Highlights Metal ion (Mn+) coordination cross‐linking synergistic strategy is proposed. Tannins/Fe3+/CNCs/PVA form multiphase nanolayers. Metal ion coordination cross‐linking enhances delicate multiphase structures. The prepared carbon fiber composites exhibit excellent properties. The as‐prepared carbon fiber composite has promising applications.

Section: Resultsmentioning

confidence: 99%

Bio‐inspired metal ion coordination cross‐linking synergistic strategy to enhance the interfacial properties of carbon fiber composites

Quan,

Wu,

Zhang

et al. 2023

Carbon fiber in situ grown ZIF‐67 nanocrystals with excellent electrochemical and interfacial property

Pu,

Yang,

et al. 2023

Carbon fiber(CF) reinforced flexible composites had a wide range of applications. However, the interfacial adhesion of composites was weak as a result of the smooth and chemically inert CF surface. To settle this issue, this paper described a method to enhance the specific surface area, roughness and wettability of the CF surface by in situ growing Cobalt‐based zeolitic imidazolate framework (ZIF‐67) nanocrystals and CF reinforced waterborne polyurethane (WPU) composites were prepared by a simple casting method. Scanning electron microscopy clearly revealed uniformly grown ZIF‐67 nanoarrays with distinct morphology on the CF surface. As a result, the CF@ZIF‐3 electrode exhibited excellent electrochemical property, with specific capacitance reaching 368.2 mF/cm2. The reinforcing effect of ZIF‐67 with different morphology was further verified through transverse fiber bundle tension test and shear bonding strength measurements, showing improvements of 51.9 and 72.1% respectively, in comparison to the CF/WPU composites due to the unique structure of the ZIF‐67 nanocrystals acted as buffer area, effectively relieving stress concentration and altering the direction of crack propagation. As a result, the interfacial properties of the composites were enhanced. Moreover, tensile and tear strengths of CF@ZIF/WPU composites showed remarkable improvement compared to CF/WPU composites. This study presented a potential reinforcement strategy for achieving high‐performance CF/WPU composites.Highlights ZIF‐67 with different morphologies were grown in situ on the CF surface. CF@ZIF electrode exhibited excellent electrochemical property. ZIF‐67 interface layer improved interfacial properties of composites. The tensile strength of the composites improved after ZIF‐67 modification. Introduction of ZIF‐67 enhanced the tear strength of composites.

Effectively improve the mechanical properties of carbon fabric/epoxy composites by oxidized carbon nitride

Zhu,

Lu,

Fan

et al. 2023

Self Cite

In this work, carbon nitride (C3N4) powder was oxidized by the Hummers oxidation method, and oxidized carbon nitride (O‐C3N4) was obtained. Epoxy (EP) was modified with O‐C3N4, and then carbon fiber fabric/epoxy (CF/EP) composites were prepared by hand‐pasting molding. The O‐C3N4 greatly improves the wettability of EP resin, enhances the interface properties of CF/EP composites, and makes the composites have better mechanical properties. The interlaminar shear strength (ILSS) is increased from 51.75 to 59.68 MPa, the tensile strength is increased from 564.54 to 635.39 MPa, the bending strength is increased from 809.64 to 938.81 MPa, and the impact strength is increased from 73.48 to 84.84 kJ/m2. Meanwhile, the dynamic mechanical properties of composites are also significantly improved. The energy storage modulus is increased from 14.9 to 21.4 GPa, with an increase of 43.6%.Highlights Developing carbon fiber composites is conducive to industrial applications. O‐C3N4 effectively improves the mechanical properties of the composite. O‐C3N4 has the advantages of simple synthesis, low costs, and light color. O‐C3N4 is rich in oxygen‐containing functional groups.