Syntheses, characterization and binding strength of geopolymers: A review

Abstract

There exist a large number of raw materials sources rich in alumina and silicon with the potential for procuring geopolymers. Among the materials predominate fly ash, calcined clays, puzzolans, kaolins, illite/smectite, metakaolins and slags. Geopolymers results from the reaction of aluminosilicate powder with an alkaline silicate solution. It has been brought to lime light that geopolymer display several usefulness in thermal insulation, thermal shock refractories, production of low energy ceramic tiles, cements and concretes, high-tech composites for aircraft interior and automobile, high-tech resin systems, in radioactive and toxic waste containment, arts and decoration. Geopolymers are generally known to have high compressive strength, fire and acid attack resistance, low water absorption capacity and thermal conductivity. This paper describes different materials suitable for procurement of geopolymer and reviews the trend in the compressive strength and water absorption of different types of synthesized geopolymers. The findings of this study, shows that compressive strength of geopolymer increases with increase in concentration of sodium silicate as well as sodium hydroxide and water absorptivity of any geopolymer decreases with increase in concentration of sodium hydroxide, water glass and duration of the geopolymer curing time