Click reactions of spherosilicates and polyhedral oligomeric silsesquioxanes. : a novel strategy towards hybrid materials

Abstract

In the last decade inorganic-organic hybrid materials have attracted much attention due to their improved properties arising from the synergetic junction of the two components. For instance optimizing mechanical, thermal or optical properties as well as hydrophobicity, permeability, catalytic properties and many more can provide new materials with user-defined features1-3. Aim of this work was to find a simple and effective pathway for a covalent connection between the inorganic and organic component in such materials. While several methods were used for the covalent connection of the components previously, such as hydrosilation reaction4-7, copolymerization of functional macromonomers8,9 or the use of macroinitiators10,11, this work will study the click chemistry bond formation between inorganic building blocks based on spherosilicates and silsesquioxanes or on mixtures of spherosilicates and polymers. For this purpose full eight corner azide and alkyne modified silica cages were prepared. Azide end-modified poly(methyl methacrylate) and polydimethylsiloxane with alkyne end-groups were used as polymeric matrices. The two components were covalently connected by Huisgen 1,3-dipolar cycloaddition reaction to give a hybrid material.