Soft-matter led hardening of concrete: enhancement of compressive and thermal strength of concrete by polymers and nanoparticles

Abstract

In this study we have shown dislocations/defects can be introduced in the form of supramolecularly bound polyacrylic acid and urea based scaffold networks and metal oxide nanoparticles in concrete. By virtue of their supramolecular bonding sites, polyacrylic acid and urea create a network of struts. These struts act as dislocations in an otherwise uniform concrete structure which in turn increase the strength of the concrete. We have also shown that the length of these struts can also be controlled. Such a control over the strut length also led to influencing the strength of the concrete. In short we have shown that effective stress for unit matrix area can be reduced by introducing defects/dislocations in the form of struts which distribute the external applied stress. Consequently the higher the extent of dislocation, the larger is the capacity of the concrete matrix to withstand externally applied stress, the higher is its mechanical strength. We further added ZrO₂ and TiO₂ nanoparticles to the concrete matrix which enhance the thermal resistivity of the concrete.