Fabrication of pH-sensitive poly(2-(diethylamino)ethyl methacrylate)/palygorskite composite microspheres via Pickering emulsion polymerization and their release behavior

ABSTRACT The poly(2‐(diethylamino)ethyl methacrylate)/palygorskite (PDEAEMA/PAL) composite microspheres were prepared via Pickering emulsion polymerization using palygorskite (PAL) as an emulsifier. The morphology, chemical structure, and content of PDEAEMA/PAL composite microspheres were investigated by polarizing optical microscopy, scanning electron microscopy (SEM), Fourier‐transform infrared (FT‐IR) spectroscopy, and thermal gravimetric analysis (TGA). The pH‐responsive behavior of composite microspheres was studied by measuring their size at different pH values. Furthermore, their release behavior was investigated using rhodamine B (RhB) as a model molecule. It was proven that the release properties of RhB from PDEAEMA/PAL composite microspheres could be controlled by adjusting the pH values. The study of release kinetics found that Higuchi model was fit for RhB release from PDEAEMA/PAL composite microspheres at pH 5.0, 7.4, and 10.0. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42179.