caa a22 4500 463222199 CHVBK 20180405153215.0 cr unu---uuuuu 170326e20070801xx s 000 0 eng 10.1007/s10853-006-1409-5 doi (NATIONALLICENCE)springer-10.1007/s10853-006-1409-5 Physical properties of methyltrimethoxysilane based elastic silica aerogels prepared by the two-stage sol-gel process [Elektronische Daten] [Nagaraja Hegde, A. Venkateswara Rao] The experimental results on the physical properties of methyltrimethoxysilane (MTMS) based elastic silica aerogels prepared by the two stage sol-gel process, are reported. The molar ratio of methanol (MeOH)/MTMS, (M), was varied from 14 to 42 and the molar ratios of acidic water/MTMS, (A) and basic water/MTMS, (B) were each varied from 0.8 to 7.2. The acidic water and basic water concentrations were also varied from 0-0.1M and 6-13.36M, respectively. The MTMS based superhydrophobic elastic aerogels could be obtained by adding only distilled water without an acid in the first step which would prevent the possible corrosion of the autoclave during the supercritical drying. With an increase in the MeOH/MTMS molar ratio, the aerogels have been found to become flexible which was characterized by the Young's modulus. The best quality elastic superhydrophobic aerogels in terms of contact angle (160°), density (37kg/m3), volume shrinkage (6%), porosity (98%) and thermal conductivity (0.057Wm−1K−1) have been obtained for the molar ratio of MTMS:MeOH:acidic water:basic water:: 1:35:3.97:3.97, respectively. The hydrophobicity was confirmed by Fourier Transform Infrared (FTIR) spectroscopy and contact angle measurements. The microstructure of the aerogels has been studied by the transmission electron microscopy (TEM). Springer Science+Business Media, LLC, 2007 Hegde Nagaraja Air Glass Laboratory, Department of Physics, Shivaji University, 416 004, Kolhapur, Maharashtra, India aut Venkateswara Rao A. Air Glass Laboratory, Department of Physics, Shivaji University, 416 004, Kolhapur, Maharashtra, India aut Journal of Materials Science Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 42/16(2007-08-01), 6965-6971 0022-2461 42:16<6965 2007 42 10853 https://doi.org/10.1007/s10853-006-1409-5 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10853-006-1409-5 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Hegde Nagaraja Air Glass Laboratory, Department of Physics, Shivaji University, 416 004, Kolhapur, Maharashtra, India aut NATIONALLICENCE 700 1- Venkateswara Rao A. Air Glass Laboratory, Department of Physics, Shivaji University, 416 004, Kolhapur, Maharashtra, India aut NATIONALLICENCE 773 0- Journal of Materials Science Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 42/16(2007-08-01), 6965-6971 0022-2461 42:16<6965 2007 42 10853 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer