Core–shell octa(azidopropyl) POSS–PEO micelle via “click” chemistry

Abstract

An amphiphilic OAPS–PEO was synthesized by “click” reaction between octa(azidopropyl) POSS (OAPS) and propargyl-terminated PEO. The structure of OAPS–PEO was characterized by nuclear magnetic resonance (NMR). The amphiphilic properties and aggregation process of OAPS–PEO in aqueous solution were investigated by fluorescence, dynamic and static light scattering (DLS and SLS), and transmission electron microscopy (TEM). The critical aggregates concentration was determined at ~0.10mg/mL using fluorescence measurements. At this concentration, unassociated unimolecular micelles with diameter size of 40–50nm were found by DLS, and were also studied by means of TEM. At a lower concentration, all the OAPS–PEO self-assembled into loose balls. With the increase of the OAPS–PEO polymer concentration, OAPS centralizes to be the core of the aggregates. At the concentration of 2.0mg/mL, aggregates present to be a core–shell structure.