Paper Number
PO6 

Session
Poster Session

Title
Early-stage rheological development and kinetics of geopolymers in exploration of sustainable alternatives to cement

Presentation Date and Time
October 12, 2022 (Wednesday) 6:30

Track / Room
Poster Session / Riverwalk A

Authors (Click on name to view author profile)

  1. Hartt IV, William H. (University of Delaware, Chemical and Biomolecular Engineering)
  2. Mills, Jennifer N. (University of Delaware, Chemical and Biomolecular Engineering)
  3. Wagner, Norman J. (University of Delaware, Chemical and Biomolecular Engineering)

Author and Affiliation Lines (in printed abstract book)
William H. Hartt IV, Jennifer N. Mills and Norman J. Wagner
Chemical and Biomolecular Engineering, University of Delaware, Newark, DE 19716

Speaker / Presenter 
Hartt IV, William H.

Keywords
construction materials

Text of Abstract
Geopolymers are inorganic polymers comprised of an aluminosilicate source and an alkali-activating solution. These materials offer terrestrial opportunities as a sustainable alternative to modern cements, with drastic reduction in CO2 emissions, as well as extraterrestrial applications for in-situ resource utilization [1]. Black Point-1 (BP-1) is a lunar regolith simulant that is characteristic of many geopolymer source materials and is the focus of this study as it allows for exploration for both proposed end-uses.
In this work, we present an early-stage kinetic investigation of BP-1 geopolymers, with small amplitude oscillatory shear (SAOS) experiments used to probe the formation kinetics. The composition is varied to study the effect of the nominal ratios of Si/Al and Si/Na on the kinetics of rheological property development as well as seven-day compressive material strength of the geopolymer. A master curve describing the early-stage rheological growth of model geopolymer gels [2] is extended to the BP-1 geopolymers. This enables comparing the kinetics of formation of the BP-1 geopolymer material to that of a model geopolymer binder of sodium aluminosilicate hydrate (N-A-S-H) gel. Applying this model allows us to explore the underlying kinetics of geopolymer formation by connecting fundamental theory and the composition to the rheological behavior. These results are used within the framework of a rheology-informed neural network (RhINN) [3] in a broader effort to predict geopolymer formation kinetics and final properties over a wider range of chemical compositions. Understanding the kinetics of the development of rheological properties as a consequence of structure formation is critical for design and optimization of geopolymer processing in the pursuit of sustainable construction materials based on geopolymers.
1. J.N. Mills, et. al. Adv. Sp. Res. 69 (2022)
2. J.N. Mills, N.J. Wagner. Rheol. Acta. (in press)
3. M. Mahmoudabadbozchelou, et. al. Proc. Natl. Acad. Sci. 119 (2022)