Mechanical and Microstructural Performance of Ultrasonically Synthesized Nano-Chitosan/PVA/Corn Cob Ash Hybrid Composite in Cement Mortar

Nanotechnology has emerged recently as a successful technique to enhance cement-based material performances. When nanoparticles, polymers and other material are added to the cement, it changes microstructure of cement composites drastically. This study synthesized a nano chitosan incorporated PVA-Corn Cob Ash (CCA) hybrid composite by using ultrasonic dispersion and incorporated it in the cement mortar. Mortar mixes were made with a cement-to-sand ratio of 1:2.75 and a water-to-cement ratio of 0.485. The hybrid composite was added at one percent by weight of cement. As per ASTM C109, the compressive strength was evaluated at 7 days and water absorption and density were determined as per ASTM C642. The time of setting was measured as per ASTM C191. The findings indicate that the hybrid composite enhances compressive strength and yields a denser cement matrix than the control mixture. The improved properties are due to the nuleation of the nano-chitosan particles, the formation of polymer film by PVA, and the pozzolanic reaction of corn cob ash. The use of agro waste materials in a hybrid system is useful for sustainable construction.