New hybrid silsesquioxane materials with sterically hindered carbosilane side groups
摘要:
Unique silsesquioxane materials, bearing highly sterically hindered carbosilane substituents at SiO3/2 centre, were derived from a novel precursor - (Me3Si)(3)CSiMe2CH2CH2Si(OEt)(3) - in a hydrolytic condensation process under nucleophilic catalysis conditions. As proved by analytical results, crystalline or ladder-like [(Me3Si)(3)CSiMe2CH2CH2SiO3/2](n) (PTSiSS) were obtained, depending on the applied reaction conditions. Due to the intrinsic features of (Me3Si)(3)CSiMe2-carbosilane substituent (the bulk and large amount of Si-C bonds), the obtained ladder-like silsesquioxanes show specific properties (good solubility, low dielectric constant kappa). (C) 2008 Elsevier B.V. All rights reserved.