Reaction-induced phase separation of bis(triethoxysilyl)ethane upon sol-gel polymerization in acidic conditions

► Phase behavior of ethanol/(acidic) water/bis(triethoxysilyl)ethane system established. ► Phenomenon of slow NMR signal loss observed for some clear solutions. ► NMR signal loss attributed to microphase separation of partially hydrolyzed oligomers. ► Results may be related to microphase separation observed in other silane-based materials.