Multi-scale investigation of the degradation of alkali silicate glasses by unsaturated humidity

Autor: Majérus, Odile, Alloteau, Fanny, Biron, Isabelle, Caurant, Daniel, Charpentier, Thibault, Lehuédé, Patrice, Valbi, Valentina
Přispěvatelé: Palacin, Serge, Institut de Recherche de Chimie Paris (IRCP), Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Ministère de la Culture (MC), Centre de recherche et de restauration des musées de France (C2RMF), Ministère de la Culture et de la Communication (MCC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Structure et Dynamique par Résonance Magnétique (LCF) (LSDRM), Nanosciences et Innovation pour les Matériaux, la Biomédecine et l'Energie (ex SIS2M) (NIMBE UMR 3685), Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Jazyk: angličtina
Rok vydání: 2022
Předmět:
Zdroj: 26th International Congress on Glass
26th International Congress on Glass, Jul 2022, Berlin, Germany
Popis: International audience; Unsaturated atmospheric conditions (defined by a relative humidity, RH < 100 %) are considered as mild and not fundamentally differing from the immersion conditions regarding the alteration of glass. The degradation processes induced by unsaturated humidity are nonetheless specific, as notably observed in the cultural heritage. In this work, we addressed the mechanisms of glass atmospheric alteration, by the mean of ageing experiments at 85 RH% as a function of time and temperature of model glass samples. Three alkali lime silicate glass compositions have been studied, two are representative of "unstable" glass compositions of the CH, and one is a soda-lime silicate glass representative of a "stable" glass. The two unstable compositions were characterized by a high speed of hydration that even increased in the timescale of the experiments (up to 9 months at 40°C, 85 RH%), while the stable composition hydrated at a rate two orders of magnitude lower. The dependency of these hydration kinetics on temperature was not arrhenian, revealing a self-acceleration mechanism involving several processes. The multispectroscopic study (EDX, TOF-SIMS, NMR, IR, Raman) of the hydrated layer indicates that unstable compositions retained a significant proportion of alkalis and non-bridging oxygens in the hydrated surface layer, while the stable composition showed a complete chemical transformation of the surface layer into a stack of alkali- and Ca-carbonate salts (on the top) and silica (at the interface with pristine glass).
Databáze: OpenAIRE