Formation of SiON networks from silsesquiazanes

Silsesquiazanes bearing different groups [RSi(NH) 1.5 ] n (R = C 12 H 25 , Ph, H) were hydrolyzed and the resulting products were characterized. [C 12 H 25 Si(NH) 1.5 ] n was hydrolyzed by heating in an autoclave with water at 120 °C for 16 h. [PhSi(NH) 1.5 ] n was hydrolyzed by heating with water at 50 °C for 16 h. [HSi(NH) 1.5 ] n was dispersed in water at room temperature to induce hydrolysis. In the cases of [C 12 H 25 Si(NH) 1.5 ] n and [PhSi(NH) 1.5 ] n , IR analysis showed that SiNHSi bonds remained and that terminal SiNH 2 bonds in silsesquiazane were preferentially hydrolyzed to form SiOH bonds or SiOSi bonds. Solid‐state 29 Si CP/MAS NMR analysis revealed the formation of a SiON network containing various Si environments. All the SiH and SiN bonds in [HSi(NH) 1.5 ] n , on the other hand, were converted into SiO bonds. These results reveal that SiON networks can be formed from silsesquiazanes bearing dodecyl and phenyl groups under relatively moderate conditions. Copyright © 2010 John Wiley & Sons, Ltd.