Procedia Engineering 57 (2013) 200 – 206 1877-7058 © 2013 The Authors. Published by Elsevier Ltd. Open access under CC BY-NC-ND license. Selection and peer-review under responsibility of the Vilnius Gediminas Technical University doi:10.1016/j.proeng.2013.04.028 11th International Conference on Modern Building Materials, Structures and Techniques, MBMST 2013 Synthesis of Silica Aerogel by Supercritical Drying Method Tomasz Błaszczyński a , Agnieszka Ślosarczyk b ∗ , Maciej Morawski c Institute of Structural Engineering, Faculty of Civil and Environmental Engineering, Poznan University of Technology, Piotrowo St. 5, 60-965 Poznań, Poland Abstract The purpose of this paper was to prepare the silica aerogel using the sol-gel and supercritical drying processes. The supercritical drying was chosen as the most effective process, ensuring the best properties of product. For this reason the authors designed and built the supercritical dryer stand that allowed drying samples in high pressure and elevated temperature. The obtained silica aerogels exhibited good transparency, homogeneity, and comparable density. The specific surface measured by means of BET analysis equaled 870.5 g/cm 3 . © 2013 The Authors. Published by Elsevier Ltd. Selection and peer-review under responsibility of the Vilnius Gediminas Technical University. Keywords: nano-composites, silica aerogel, sol-gel polymerization, supercritical drying, BET analysis. 1. Introduction Fast growth of technique increases energy demands in everyday life, forcing the scientific world to look for modern and more efficient solutions which can help save the energy. Residential and commercial retrofit insulation has been found as one of the most cost effective actions for greenhouse gas abatement. Therefore, traditional insulation materials were and are being used in thicker or multiple layers which result in more complex building details, an adverse net-to gross floor area and heavier load bearing constructions [1]. One of the most interesting science of the material engineering which has been recently indicated rapid development is nanotechnology. Nanotechnology is a science concerning nanomaterial – a policrystalic substances compose of grains smaller than 100 nanometres, at least in one direction [2]. The purpose of this paper was to prepare the silica aerogel – nanomaterial which was firstly discovered about 1930 by Dr Samuel Stephen Kistler. This fascinating nanomaterial is made of more than 90% of air, what guarantee an excellent thermal conductivity, extremely low weight, and moreover, the transparency of aerogel. All those properties make aerogel an ideal material for thermal insulation of walls as well as windows, causing the decrease of heat and energy consumption [3], [4]. The aerogel can be prepared in different ways including supercritical drying process. This particular process was chosen as the most effective one, ensuring the best product properties. For this reason the authors designed and built the supercritical dryer stand that allows drying samples in high pressure and elevated temperature. 2. Chemistry of aerogel synthesis Nanomaterials and/or nanoparticles are used in a broad spectrum of applications. Today they are contained in many products and used in various technologies. Most nanoproducts produced on an industrial scale are nanoparticles, although they also arise as byproducts in the manufacture of other materials.   * Corresponding author. E-mail address: a tomasz.blaszczynski@put.poznan.pl; b agnieszka.slosarczyk@put.poznan.pl; c mormac@interia.pl Available online at www.sciencedirect.com © 2013 The Authors. Published by Elsevier Ltd. Open access under CC BY-NC-ND license. Selection and peer-review under responsibility of the Vilnius Gediminas Technical University