Self-Assembly of Bridged Silsesquioxanes: Modulating Structural Evolution via Cooperative Covalent and Non-covalent Interactions
Résumé
The self-assembly of a bis-urea phenylene-bridged silsesquioxane precursor during sol-gel synthesis has been investigated by in situ infrared spectroscopy, optical microscopy and light scattering. In particular, the evolution of the system as a function of processing time was correlated with covalent interactions associated with increasing polycondensation and non-covalent interactions such as hydrogen bonding. A comprehensive mechanism based on the hydrolysis of the phenylene-bridged organosilane precursor prior to the crystallization of the corresponding bridged silsesquioxane via H bonding and subsequent irreversible polycondensation is proposed.