Polysiloxanes Grafted with Mono(alkenyl)Silsesquioxanes-Particular Concept for Their Connection

Herein, a facile and efficient synthetic route to unique hybrid materials containing polysiloxanes and mono(alkyl)silsesquioxanes as their pendant modifiers (T₈@PS) was demonstrated. The idea of this work was to apply the hydrosilylation reaction as a tool for the efficient and selective attachment of mono(alkenyl)substituted silsesquioxanes (differing in the alkenyl chain length, from -vinyl to -dec-9-enyl and types of inert groups iBu, Ph at the inorganic core) onto two polysiloxanes containing various amount of Si-H units. The synthetic protocol, determined and confirmed by FT-IR in situ and NMR analyses, was optimized to ensure complete Si-H consumption along with the avoidance of side-products. A series of 20 new compounds with high yields and complete β-addition selectivity was obtained and characterized by spectroscopic methods.