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Journal of Materials Science

, Volume 51, Issue 2, pp 719–731 | Cite as

Control of porous structure in flexible silicone aerogels produced from methyltrimethoxysilane (MTMS): the effect of precursor concentration in sol–gel solutions

  • M. Du
  • N. Mao
  • SJ Russell
Original Paper

Abstract

Controllable nanoporous structure in MTMS-based silicone aerogels is required to improve their thermal conductivity. Silicone aerogels were formed in a two-step acid–base catalysed sol–gel process combined with supercritical drying. The influence of MTMS concentration, specifically the molar ratio of methanol:MTMS and water:MTMS in the sol–gel process was studied in relation to the porous structure of resultant silicone aerogels. Samples were characterised to determine the dimensions of micro, meso and macro-pore structure by means of both nitrogen gas adsorption–desorption for detection of pores <300 nm and by analysis of FEG-SEM images for pores >300 nm. Porosity, pore volume distribution and Brunau er–Emmitt–Teller surface area in the silicone aerogels were all found to be influenced by adjustment of the molar ratio of methanol:MTMS and the molar ratio of water:MTMS during sol–gel processing.

Keywords

Pore Size Distribution Total Pore Volume Silica Aerogel True Density Mesopore Volume 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgements

We would like to thank the financial support of Overseas Research Studentship (UK) and the University of Leeds Research Studentship for the research project.

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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  1. 1.Performance Textiles and Clothing Research Group, School of DesignUniversity of LeedsLeedsUK

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