D 2 ‐ meta ‐carborane‐siloxanes. IV. Synthesis of linear, high molecular weight polymers

A new facile route to linear, high molecular weight D 2 ‐ meta ‐decacarborane‐siloxanes was developed based on the condensation reaction between bisureidosilanes and carborane disilanol. By using NMR to monitor the reaction stoichiometry, polymers with molecular weight ≥250,000 have been prepared. Moreover, because of the mild reaction conditions, structural modifications of the polymer backbone have been readily achieved. These linear, high molecular weight polymers overcome the fabrication difficulties encountered in previously prepared D 2 ‐polymers.