Exploiting the synergetic effects of graphene and carbon nanotubes on the mechanical properties of bitumen composites

• Published in: Carbon (New York) 2021-02, Vol.172, p.402-413
• Main Authors: Yang, Qilin, Qian, Yue, Fan, Zepeng, Lin, Jiao, Wang, Dawei, Zhong, Jing, Oeser, Markus
• Format: Article
• Language: English
• Subjects: Bitumens; Carbon; Carbon nanotubes; Composite materials; Contact stresses; Creep (materials); Crosslinking; Deformation; Deformation resistance; Dispersion; Graphene; Hybrid structures; Low temperature; Low temperature resistance; Low-temperature performance; Mechanical properties; Nanomaterials; Rheological property; Stress transfer; Synergetic effects
• ISSN: 0008-6223; 1873-3891
• DOI: 10.1016/j.carbon.2020.10.020

Functional carbon nanomaterials are incorporated in bitumen composites to enhance their mechanical performance; however, this process is significantly hindered by the poor dispersion of the nanomaterials in the bitumen composite bulk, and their sluggish interfacial interaction with the bitumen matrix. In this study, graphene/carbon nanotube (CNT) hybrid materials were used to reinforce a bitumen composite, exhibiting improved dispersion, while advancing the interfacial interactions between the carbon nanomaterials and the bitumen matrix. Comparing with the control bitumen sample, a Bitumen/Graphene composite and a Bitumen/CNT composite, the graphene/CNT hybrid notably improved several properties of the bitumen structure, such as rutting resistance, creep and recovery behavior, permanent deformation resistance, low-temperature cracking resistance and the degree of crosslinking in the bitumen. In particular, bitumen binders with 0.2 wt% graphene and 0.8 wt% CNT composite presented the optimal mechanical performance. These improvements can be attributed to the synergetic effects of the material and the formation of 1D-2D hybrid structures, which apart from increasing the contact area, effectively enhanced stress transfer at graphene/CNT and bitumen interface. [Display omitted] •A hybrid graphene/CNT nanostructure was designed and homogeneously dispersed and embedded in a bitumen composite.•Hybrid graphene/CNT significantly enhanced the high-temperature performance of bitumen.•Hybrid graphene/CNT remarkably improved the low-temperature cracking resistance and crosslinking degree of bitumen.•Bitumen with 0.2 wt% graphene and 0.8 wt% CNT exhibited the optimal mechanical properties.