|About this Abstract
||Materials Science & Technology 2020
||Journal of the American Ceramic Society Awards Symposium
||Advances in Polymer-assisted Sol-gel Synthesis of Aluminosilicate Precursors for Modern Cementitious Materials
||Juan Pablo Gevaudan, Jaqueline D. Wallat, Bimala Lama, Wil V. Srubar
|On-Site Speaker (Planned)
||Juan Pablo Gevaudan
This presentation explores recent advances and future trajectories in the utilization of polymer-assisted sol-gel (PSG) synthesis to produce modern cementitious materials. By leveraging nuclear magnetic resonance, X-ray diffraction and infrared spectroscopy experiments, we demonstrate how critical PSG factors (e.g., pH aging conditions, ion concentration, polymer type and architecture) affect the atomic structure of a sodium-stabilized aluminosilicate hydrate (N-A-S-H) geopolymer cement. More specifically, results demonstrate that polymer architecture is a key factor in producing undesirable phase segregation and incomplete dehydroxylation (vicinal silanol) in cement precursors. PEG-derived aluminosilicate precursors yield partial dissolution and produce geopolymer cements with variable silicate incorporation. Contrastingly, PVA-derived aluminosilicate powders produce geopolymer cements with identical mineralogy to that of metakaolin-based geopolymer cements and exhibit both Brønsted-acid sites near the aluminum nuclei and geminal silanol groups. We hypothesize three plausible metal-complexation processes of PSG, which can be leveraged to postulate future trajectories in the manufacturing of sustainable cementitious materials.