@article{7d2873e435d64c22b44476d34e85b326,
title = "Isolating the effects of thixotropy in geopolymer pastes",
abstract = "The rheological properties of potassium-based geopolymers were investigated through a series of experiments intended to isolate the influence of shear rate, recovery time, and shear ramping on thixotropy for a greater understanding of geopolymer thixotropic properties within the context of the geopolymer setting reaction. It is shown that for thixotropic disruption to occur a critical shear rate of 100 s−1 must be reached or surpassed, full thixotropic restructuring occurs at around 90–100 min of total undisturbed rest time, and that reaching a state of full thixotropic disturbance heavily depends on subjected processing parameters. In addition, a consistent crossover between the storage and loss modulus within 1–3 min of oscillation during cyclical oscillatory measurements greatly indicates the repeatability and reversibility of thixotropy in geopolymers and the potential for tailorable viscosity. Overall, it is found that geopolymer pastes exhibit strong evidence of thixotropy, which is favorable for additive manufacturing, and that allotted rest time before shear and shear rate greatly influence the overall rheological properties.",
keywords = "aluminosilicates, geopolymers, rheology/rheometry, viscosity",
author = "Brandvold, {Allison S.} and Al-Chaar, {Ghassan K.} and Kriven, {Waltraud M.}",
note = "Funding Information: We gratefully acknowledge the financial support of the US Army Corps of Engineers under Contract number Army W9132T‐21‐C‐0005 AH571 through the Engineer Research Development Center (ERDC) and the Construction Engineering Research Laboratory (CERL) in Champaign, IL, USA. We thank Dr. Remy Roddel in the Center for Microanalysis of Materials at the Frederick Seitz Materials Research Laboratory (MRL) of UIUC for the help provided to become familiar with the Discovery Hybrid Rheometer (DH2R) instrument, Nicole Robards for access to the rheometer and Dr. Ali Ozer for conducting XRF for this study in the MRL. Lastly, we would like to thank Prof. John Popovics of the Department of Civil and Environmental Engineering at UIUC and his graduate student, Sangmin Lee, for their gracious help teaching the author Allison Brandvold about UWR and for allowing us to borrow their equipment. Funding Information: We gratefully acknowledge the financial support of the US Army Corps of Engineers under Contract number Army W9132T-21-C-0005 AH571 through the Engineer Research Development Center (ERDC) and the Construction Engineering Research Laboratory (CERL) in Champaign, IL, USA. We thank Dr. Remy Roddel in the Center for Microanalysis of Materials at the Frederick Seitz Materials Research Laboratory (MRL) of UIUC for the help provided to become familiar with the Discovery Hybrid Rheometer (DH2R) instrument, Nicole Robards for access to the rheometer and Dr. Ali Ozer for conducting XRF for this study in the MRL. Lastly, we would like to thank Prof. John Popovics of the Department of Civil and Environmental Engineering at UIUC and his graduate student, Sangmin Lee, for their gracious help teaching the author Allison Brandvold about UWR and for allowing us to borrow their equipment. Publisher Copyright: {\textcopyright} 2023 The Authors. Journal of the American Ceramic Society published by Wiley Periodicals LLC on behalf of American Ceramic Society.",
year = "2023",
doi = "10.1111/jace.18996",
language = "English (US)",
volume = "106",
pages = "2797--2807",
journal = "Journal of the American Chemical Society",
issn = "0002-7863",
publisher = "American Chemical Society",
number = "5",
}