New multi-scale cementitious composites developed using carbon nanotubes and microcrystalline cellulose

Abstract

Due to remarkable mechanical properties, various nanomaterials are now being considered as effective reinforcements of cementitious composites. In the present study, new multi-scale cementitious composites were developed using carbon nanotubes (CNTs) and micro crystalline cellulose (MCC) as a hybrid reinforcement system. To develop these composites, CNTs and MCC were homogeneous dispersed in aqueous suspension using ultrasonication energy and a nonionic surfactant, Pluronic F-127. These aqueous suspensions were then mixed with cement/sand mixture to fabricate the cementitious composites. Workability, mechanical properties and microstructure of the developed composites were thoroughly characterized. According to the experimental observations, flexural stiffness of cementitious composites improved strongly due to the hybrid reinforcements, as shown in Fig. 1. Also, flexural strength improved significantly (~13%) using 0.1% CNT and 0.2% MCC, dispersed using 3% Pluronic. The workability of the cement paste, on the other hand, was not significantly influenced due to the reinforcing materials. Future efforts are being directed towards optimizing the dispersion conditions of CNT and MCC to further enhance the mechanical performance of these new composites.