Improvement of Compression Strength of Silica Aerogel Using Poly Ethylene Glycol

Silica aerogels are nanoporous lightweigth solids which are valuable materials for insulation, chemical adsorbent and fubricating nano composites due to their special properties. Fragility and brittleness of silica aerogels are their constraints. There are several techniques to make them suitable substances for practical applications. In the present research silica aerogel is synthesized through two step sol-gel process using tetraethyl orthosilicate (TEOS) as the precursor. Poly Ethylene Glycol (PEG) with three different molecular weights in five different concentrations is added as a chain extender during the reaction to improve the flexibility and compression strength of polymer chains. The compression strength and maximum elongation at break as well as the density that show physical and mechanical properties of the samples are determined. The experimental finding shows that there is optimum amount of molecular weight and concentration of PEG that lead to the maximum compression strength and flexibility.