Influence of Choice of Curing Method on the Dielectric, Thermal and Mechanical Properties of Geopolymer Mortar-Natural Rubber Latex (GM-NRL) Blends

Abstract

This study sought to improve the geopolymer properties by adding natural rubber latex (NRL), with appropriate level of that addition determined experimentally, and to test alternative heating methods for curing. Conventional hot-air and microwave heating alternatives were tested singly and in combinations, with microwave heating as first or last in the combination. The GM-NRL properties observed were thermal, dielectric, and mechanical properties. The tested NRL addition levels were 5, 8, and 10% by weight of lignite fly ash. It was found that as the amount of NRL was increased, also water demand and hardening time of the geopolymer increased. Thermal conductivity (K) and specific heat (Cp) depended on the density of a cured specimen. NRL level of 10% by weight caused sharp drops in K and Cp. The NRL addition tended to increase dielectric characteristics while decreasing compressive strength. However, microwave curing gave superior compressive strength over the other curing methods tested.