Mechanical properties of carbon nanotube–micro crystalline cellulose reinforced multi-scale cementitious composites

This work has been performed to study the mechanical properties of multiscale cementitious composites developed by using microcrystalline cellulose (MCC) and multi-wall carbon nanotubes (MWCNTs) as reinforcements. The experimental work was carried out in two steps: (a) homogeneous suspensions of MCC (0.4 wt.% and 1 wt.%) and CNTs (0.2% and 0.6%) in water were prepared using cetyl trimethylammonium bromide (CTAB) surfactant and ultra-sonication energy and (b) the suspensions were subsequently added to cement/sand mixture to fabricate cementitious composites. The composite samples were kept for 56 days to carry out hydration and were then characterized for flexural properties. It was observed that flexural strength of cement mortar improved significantly when it was reinforced with MCC and CNT together. The highest improvement of flexural strength of 12.14% was achieved with MCC loading up to 0.5 wt.% and CNT of 0.3 wt.%. Considerable improvement in the flexural modulus of cement mortar was also achieved using this hybrid reinforcement system