Effects of addition of hybrid nanocomposite based on polysaccharide hydrogel and nanoclay on the fresh and hardened properties of cementitious mortars

Abstract

Mortars are heterogeneous composites that gain strength through a succession of chemical reactions between water and Portland cement. In this sense, hydrophilic polymers that can absorb water and release it later have been developed to improve their properties. Thus, a hydrogel-based on polyacrylamide, carboxymethylcellulose and nanoclay was synthesized and applied in cement mortars prepared with different water/cement (w/c) ratios (0.40, 0.48, and 0.50). Its application in mortars reduced the consistency index and the exudation rate and did not cause variation in density in the hardened state. The water absorption rate of mortars with hydrogel with w/c= 0.40 and 0.50 reduced ~6.1% and 6.7%, respectively. This same behavior was also observed for compressive strength. In summary, the development and application of hydrogels capable of absorbing and releasing water is a very promising area for civil construction.

Keywords:
civil construction; compressive strength; nanocomposite; hydrogel; Portland cement