Synthesis and characterization of ambient dried hydrophobic and flexible silica aerogel

Flexible and hydrophobic silica aerogel is produced by polycondensation reaction of methyl trimethoxysilane (MTMS) precursor. The effects of various process parameters such as molar ratio of methanol/MTMS and H2O/MTMS on flexibility and physicochemical properties of the silica aerogel have been investigated. The introduced method is able to produce hydrophobic aerogels at ambient conditions with no need of solvent exchange and surface modification. The hydrophobic aerogels has been characterized by flexibility, bulk density and percentage of volume shrinkage. It has been observed that the process variables play crucial roles in flexibility of obtained monolithic silica aerogel which can be optimized by controlling methanol/MTMS and H2O/MTMS molar ratios