Multifunctional amphiphilic siloxane architectures using sequential, metal‐free click ligations

Abstract Polysiloxanes or silicones are a class of macromolecules widely used in commerce because of their exceptional properties. Their derivatization leads to functional silicones with added value and properties, such as surfactants and liquid crystals, among many others. However, most silicone surfactants are monofunctional, owing to the synthetic challenges associated with the introduction of multiple functional groups onto the hydrolytically sensitive siloxane backbone. Thus, general routes to surface active silicones with multiple and different functional groups are not available. Herein, a synthetic strategy is reported that permits sequential derivatization of silicones with hydrophiles including oligo(ethylene oxides), carboxylic acids, and bromoalkylesters using a simple metal‐free Click reaction: the process benefits from mild conditions, extremely high yields and does not generate any by‐products, allowing the facile preparation of di‐ and trifunctional silicones that could not be readily obtained using traditional methods. The products exhibit amphiphilic characteristics as demonstrated through interfacial tension measurements that yielded the critical aggregation concentration of selected compounds. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013