Title: | "Producing surfactant-synthesized nanomaterials in situ on a building substrate, without volatile organic compounds" |
Author(s): | Illescas JF; Mosquera MJ; |
Address: | "Departamento de Quimica-Fisica, Facultad de Ciencias, Universidad de Cadiz, 11510 Puerto Real (Cadiz), Spain" |
Journal Title: | ACS Appl Mater Interfaces |
ISSN/ISBN: | 1944-8252 (Electronic) 1944-8244 (Linking) |
Abstract: | "This article describes a sol-gel route for nanomaterials production, without volatile organic compounds (VOCs). These materials are simply obtained by mixing a silica oligomer with a non-ionic surfactant under ultrasonic agitation. The surfactant acts as sol-gel transition catalyst and also as an agent that directs the pore structure of the material, reducing capillary pressure during drying. Thus, a crack-free monolithic material is produced. We also synthesize a novel product with hydrophobic properties by adding OH terminal-polydimethylsiloxane to the starting sol. Importantly, since our synthesis does not require calcination or other additional procedures, the sol can be applied directly onto substrates, particularly the external surface of buildings. Thus, an application of these nanomaterials is to restore and to protect building substrates. Our in-depth investigation of the structure of these materials, using several techniques (physisorption, scanning electron microscopy, transmission electron microscopy, atomic force microscopy, nuclear resonance magnetic spectroscopy), reveals that they are composed of silica particles as a result of the role played by n-octylamine. In the hybrid materials, polydimethylsiloxane acts to form bridges linking the silica particles. Finally, we demonstrate the effectiveness of these products for consolidating one particular building stone and making it hydrophobic" |
Keywords: | "Catalysis Equipment Design Gels/chemistry Microscopy, Atomic Force/methods Microscopy, Electron, Scanning/methods Microscopy, Electron, Transmission/methods Nanostructures/*chemistry Nanotechnology/*methods Organic Chemicals/chemistry Phase Transition Sil;" |
Notes: | "MedlineIllescas, Juan F Mosquera, Maria J eng Research Support, Non-U.S. Gov't 2012/07/19 ACS Appl Mater Interfaces. 2012 Aug; 4(8):4259-69. doi: 10.1021/am300964q. Epub 2012 Jul 27" |