Details

Autor(en) / Beteiligte

• Mathivet, V.
• Jouin, J.
• Gharzouni, A.
• Sobrados, I.
• Celerier, H.
• Rossignol, S.
• Parlier, M.

Titel

Acid-based geopolymers: Understanding of the structural evolutions during consolidation and after thermal treatments

Ist Teil von

• Journal of non-crystalline solids, 2019-05, Vol.512, p.90-97

Ort / Verlag

Elsevier B.V

Erscheinungsjahr

2019

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Materials such as ceramic matrix composites are developed for mechanical applications at high temperature, but their cost remains a limitation. Consequently, the use of acid-based geopolymer matrices may be an alternative to reduce costs. In this study, the sample was prepared from metakaolin and phosphoric acid. Fourier Transform InfraRed and Nuclear Magnetic Resonance spectroscopies, X-Ray Diffraction and thermal measurements were used to understand the structural evolution of acid-based geopolymers (binders) during consolidation and after thermal treatments. According to the results, the consolidation of the binder has been divided into four steps: the dissolution of the metakaolin, the polycondensation reactions forming AlPO4 entities and hydrated phases, the breakdown of SiOAl bonds with formation of various hydrated silica networks and finally the completion of the networks. After a thermal treatment at 1000 °C, the binder consists of AlPO4 phases, quartz and vitreous silica. •The polycondensation mechanism of acid-based geopolymers is highlighted.•The different networks formed are evidenced from spectroscopy and XRD data.•Several hydrated phases and AlPO4 polymorphs crystallize during heat treatment.