Challenges of Alkoxysilane-Based Consolidants for Carbonate Stones: From Neat TEOS to Multipurpose Hybrid Nanomaterials



Alkoxysilane-based products have been used in conservation interventions to consolidate stone-built heritage, although with limited success in carbonate stones. This chapter overviews drawbacks and challenges of carbonate stone consolidation, with a focus on important phenomena related to the carbonate media particularities (possible disturbance of sol-gel routes and lack of strong chemical bond with calcite) and issues related to extended hydrolysis reactions and susceptibility to crack of the most common alkoxysilane-based products. While significant advances concerning crack susceptibility have been widely highlighted, more recent developments regarding the remaining phenomena are still scarce. Nevertheless, novel alkoxysilane-based products, based on hybrid materials, surfactant templates, nanoparticles, organosilanes, and others, have shown potential to treat carbonate stones. Some of these strategies led to the development of multifunctional products, but doubts persist whether this multifaceted role is always advantageous. This chapter discusses the most relevant research advances on the field and critically addresses issues that are worth to research further.


Carbonate stones Functional surfaces Alkoxysilanes Consolidation Ethyl silicate 



The authors acknowledge Fundação para a Ciência e Tecnologia (FCT) for the financial support, CQE—UID/QUI/00100/2013. The author B. Sena da Fonseca also acknowledges Fundação para a Ciência e Tecnologia (FCT) for the financial support through grant SFRH/BD/96226/2013.


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© Springer International Publishing AG 2018

Authors and Affiliations

  1. 1.Centro de Química Estrutural, CQE, DEQ, Instituto Superior TécnicoUniversidade de LisboaLisboaPortugal
  2. 2.Department of Civil Engineering, Architecture and Georesources, CERIS, ICIST, Instituto Superior TécnicoUniversidade de LisboaLisboaPortugal
  3. 3.Escola Superior de Tecnologia de Setúbal, Centro de Desenvolvimento do Produto e Transferência de TecnologiaInstituto Politécnico de SetúbalSetúbalPortugal

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