Reactivity of silanol group on siloxane oligomers for designing molecular structure and surface wettability

Molecular structures of siloxane materials should be highly controlled for achieving advanced functionalities. However, it is still difficult to precisely control the structure of siloxane materials by the sol–gel processing. In the present study, we focused on the silanol groups in the intermediate oligomers and resultant siloxane materials as a key structural unit for controlling the molecular structure. Thermal stability and chemical reactivity of silanol groups were found to be highly dependent on the steric effects of the surrounding side chains and siloxane skeletons. The present work suggests that controlling the steric effects around silanol groups in the intermediate oligomers allows modulating the crosslink density of siloxane skeletons. The selective molecular modification tunes the structure and chemical properties of the resultant siloxane materials. [Figure not available: see fulltext.]