Enhancement of Mechanical Properties of Cement Mortar using Zeolitic Immidazolate Frameworks (Zif-8) As an Admixture

Abstract

Nanomaterials have been used in improving strength of cement mortar and concrete as cementitious composites have high compressive strength and low ductility and toughness. Cementitious composites have nano pores in cement matrix which reduces the strength and these pores if filled with nanomaterials could increase the compressive strength. Many nanomaterials have been used to enhance the properties of cement matrix, but no research has yet been published on ZIF-8. ZIF-8 is a class of nanomaterials extracted from metallic oxide frameworks (MOFs) which closely resembles zeolites. Zeolites along with other nanoparticles like Titanium Dioxide, Boron Nitride etc, have shown remarkable increase in mechanical and durability properties of cement mortar. In this project, ZIF-8 was added in cement mortar as an admixture to investigate its performance. The results are compared with other nanoparticles like zeolites, Carbon Nano-Tubes (CNTs) and Titanium Dioxide. Since physical properties (compound structure similarity) of ZIF-8 are similar to zeolites, a positive effect on its mechanical properties is observed. At elevated temperatures, ZIF-8 framework loses its Zn atoms and breaks down to 3D carbon chains retaining their morphology which could act as carbon nanotubes but with less tensile strength.