The synthesis of phosphorylated silsesquioxanes and the investigation of the ability to aggregation and interaction with aromatic dicarboxylic acids

Abstract

© 2014 Elsevier B.V. All rights reserved. For the first time, silsesquioxanes containing aminophosphonate fragments were synthesized by condensation of the aminophosphonate derivatives with trialkoxysilane moieties under acid catalysis conditions. According to 29Si NMR, IR-spectroscopies, the silsesquioxane obtained have ladder-like structure with T4and T6silicon atoms. Information obtained from the MALDI-TOF mass spectra was used to deduce the structure of both oligomeric derivatives and the silsesquioxane framework. The morphology of the polysilsesquioxanes formed was investigated by transmission electron microscopy. The T6-silsesquioxanes bearing aminophosphonate moieties contrary to T4-silsesquioxanes tend to form aggregates of prolate shape. Their aggregation behavior was analyzed by the dynamic light scattering method. T6-silsesquioxane tends to form submicron-sized aggregates in aqueous solutions. The ability of these silsesquioxanes to recognize aromatic dicarboxylic acids was studied by the UV-spectroscopy.