Temporal dynamics of rheological properties of metakaolin-based geopolymers: Effects of synthesis parameters. (28th June 2021)

• Record Type: Journal Article
• Authors: de Gasperi, Jessica; Holthusen, Doerthe; Howes, Maria Fernanda Dornelles; Sattler, Naquiele; Longhi, Márlon A.; Rodríguez, Erich D.
• Is Part Of: Construction & building materials. Volume 289(2021)
• Publication Date: 2021-06-28
• Subjects: Geopolymers -- Alkali-activated materials -- Rheology -- Viscoelastic limit -- Time -- Workability -- Oscillatory rheometry; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2021.123145
• Languages: English
• ISSNs: 0950-0618

Abstract

Graphical abstract: Highlights: Amplitude sweep test was applied to a set of geopolymers to evaluate rheological properties. Stiffens of fresh pastes was quantified and correlated with synthesis conditions. Behavior of rheological properties over time was measured and calculated. Abstract: Despite advanced development of geopolymers, reliable methods to define their technological features are scarce. The objective of this paper is to evaluate the influence of synthesis parameters (water/binder ratio, alkaline activator type and concentration) on the temporal rheological behavior of metakaolin-based geopolymers. Oscillatory tests were conducted in rheometer with a parallel-plates system, where different rheological parameter were measured (storage/loss modulus, linear viscoelastic interval, loss factor, transition point, among others). The rheological behavior was assessed over time. From the results was identified the time period when pastes in fresh state can be handled and which synthesis conditions improve the workability.