Fractural performance of epoxy nanocomposites reinforced with carbon aerogels in different structures. (October 2021)

• Record Type: Journal Article
• Authors: Reyhani, Reyhaneh; Zadhoush, Ali; Salman Tabrizi, Nooshin; Nazockdast, Hossein; Naeimirad, Mohammadreza
• Is Part Of: Theoretical and applied fracture mechanics. Volume 115(2021)
• Publication Date: 2021-10
• Subjects: Carbon aerogels -- CNTs -- Fracture -- Toughness -- Structural properties -- Epoxy; Fracture mechanics -- Periodicals; 620.1126
• DOI: 10.1016/j.tafmec.2021.103079
• Languages: English
• ISSNs: 0167-8442

Abstract

Highlights: CNTs were used to increase the specific surface area and total pore volume of carbon aerogel. Powdered carbon aerogels were used for reinforcement of epoxy nanocomposites. The effect of changing the physical structure of the reinforcement on the fracture toughness of nanocomposites was evaluated. Two direct and indirect methods were used to evaluate the fractural parameters. Abstract: Home-synthesized carbon aerogels were used as reinforcements for epoxy nanocomposites in different weight contents (0.1, 0.3, and 0.5 wt%). The relationship between physical structure of aerogels (specific surface area and total pore volume) and mechanical properties of nanocomposites were evaluated. The fracture toughness of nanocomposites was investigated by both direct and indirect methods. The nanocomposites provided better mechanical properties than neat epoxy. Due to the penetration of polymer chains into the aerogels' pores, the filler/polymer interface was increased, which lead to an effective increase in load transfer. The porous structure of the aerogels absorbs energy and external force applied, which ultimately plays a role in properties improvement. Due to the higher specific surface area of CNT-doped carbon aerogels (CNT-CA), Ep/CNT-CA nanocomposites showed a better performance. Improvement of fracture toughness in 3-point bending test was greater than impact test. Mechanical and topographical investigations of nanocomposites showed enhancements: 106–143% KIC, 241–372% GIC, 50–58% impact strength and 10.28–14.72 nm roughness, compared to the epoxy matrix.