Hybrid siloxane-based nano building blocks for optical applications: Optimization of the synthetic procedures by spectroscopic analysis

Diphenylsilanediol (DPDO) reacts with triethoxysilane (TREOS) in anhydrous conditions and in the presence of pyridine, to form complex mixtures of linear and cyclic condensation products which were identified by Si-29 NMR and ATR/FTIR spectroscopies. The distribution of products can be varied by modifying the reaction conditions. Spectroscopic analysis allowed to identify the optimal reagents ratio and concentration for the production of hetero-condensation products minimizing the number of residual OH groups whose presence would affect the performance of optical waveguides based on the synthesised nano building blocks.