Geopolymers are hydrated aluminosilicates with excellent binding properties. Geopolymers appeal to the construction sector as a more sustainable alternative to traditional cements, but their exploitation is limited by a poor understanding of the linkage between chemical composition and macroscopic properties. Molecular simulations can help clarify this linkage, but existing models based on amorphous or crystalline aluminosilicate structures provide only a partial explanation of experimental data on the nanoscale. This paper presents a new model for the molecular structure of geopolymers, in particular for nanoscale interfacial zones between crystalline and amorphous nanodomains, which are crucial for the overall mechanical properties of the material. For a range of Si-Al molar ratios and water contents, the proposed structures are analyzed in terms of skeletal density, ring structure, pore structure, bond-angle distribution, bond length distribution, X-ray diffraction, X-ray pair distribution function, elastic moduli, and large-strain mechanics. Results are compared with experimental data and with other simulation results for amorphous and crystalline molecular models, showing that the newly proposed structures better capture important structural features with an impact on mechanical properties. This offers a new starting point for the multiscale modeling of geopolymers.

Atomistic Simulations of Geopolymer Models: The Impact of Disorder on Structure and Mechanics / Lolli, Francesca; Manzano, Hegoi; Provis, John L.; Bignozzi, Maria Chiara; Masoero, Enrico*. - In: ACS APPLIED MATERIALS & INTERFACES. - ISSN 1944-8244. - STAMPA. - 10:26(2018), pp. 22809-22820. [10.1021/acsami.8b03873]

Atomistic Simulations of Geopolymer Models: The Impact of Disorder on Structure and Mechanics

Bignozzi, Maria Chiara;
2018

Abstract

Geopolymers are hydrated aluminosilicates with excellent binding properties. Geopolymers appeal to the construction sector as a more sustainable alternative to traditional cements, but their exploitation is limited by a poor understanding of the linkage between chemical composition and macroscopic properties. Molecular simulations can help clarify this linkage, but existing models based on amorphous or crystalline aluminosilicate structures provide only a partial explanation of experimental data on the nanoscale. This paper presents a new model for the molecular structure of geopolymers, in particular for nanoscale interfacial zones between crystalline and amorphous nanodomains, which are crucial for the overall mechanical properties of the material. For a range of Si-Al molar ratios and water contents, the proposed structures are analyzed in terms of skeletal density, ring structure, pore structure, bond-angle distribution, bond length distribution, X-ray diffraction, X-ray pair distribution function, elastic moduli, and large-strain mechanics. Results are compared with experimental data and with other simulation results for amorphous and crystalline molecular models, showing that the newly proposed structures better capture important structural features with an impact on mechanical properties. This offers a new starting point for the multiscale modeling of geopolymers.
2018
Atomistic Simulations of Geopolymer Models: The Impact of Disorder on Structure and Mechanics / Lolli, Francesca; Manzano, Hegoi; Provis, John L.; Bignozzi, Maria Chiara; Masoero, Enrico*. - In: ACS APPLIED MATERIALS & INTERFACES. - ISSN 1944-8244. - STAMPA. - 10:26(2018), pp. 22809-22820. [10.1021/acsami.8b03873]
Lolli, Francesca; Manzano, Hegoi; Provis, John L.; Bignozzi, Maria Chiara; Masoero, Enrico*
File in questo prodotto:
Eventuali allegati, non sono esposti

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11585/662884
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? 7
  • Scopus 82
  • ???jsp.display-item.citation.isi??? 71
social impact