Rheology properties of metakaolin activated by lithium water glass

Abstract

Alkali-activated materials play an important role in the current industry, because they offer alternative way towards low carbon technologies. However, their crucial utilization still lays in the field of composites resistant to high temperatures, especially in the heavy machinery and chemical industry. The current paper documents rheological properties of set of pastes on the basis of Czech metakaolin as precursor, which was activated by lithium water glass exhibiting various silicate modulus. The rheological properties were studied in terms of standard flow test and optimized composition exhibiting similar workability were subsequently investigated by using rotary rheometer. The rheology was monitored in time to document performed changes during the geopolymerization. The attained flow curves were fitted by Herschel-Bulkley model and basic rheological characteristics of optimized pastes were derived. The research confirmed prolonged workability of the studied paste activated by lithium water glass and better. The pastes activated by lithium water glass of lower silicate modulus exhibited lower values of yield stress.