pH-Responsive polymers

In this review, we provide an analysis of some of the recent literature reports on the synthesis and applications of pH-responsive polymers. Depending on the solution pH, such copolymers can self-assemble and form various nanosized structures including core-shell micellar structures, micelles/reverse micelles, hollow spheres, vesicle structures, adsorbed species at the water-air interface, and more complex architectures. Their self-assembly behaviors open the door for the production of various novel nanostructures including shell/core cross-linked micelles, hollow spheres, hydrogels, microgels, layer-by-layer (LbL) nanofilms, controlled releasing systems, drug carrier systems, etc . The review consists of various major parts including types of pH-responsive polymers, synthetic methods for their synthesis and their solution behaviors, their nanostructures in aqueous media, applications as LbL nanofilms, delivery devices, controlled release systems, sensors, stabilizers, solubilizers, etc . In the last two decades, there have been great developments in synthetic methods and strategies for the preparation of novel pH-responsive polymers or polymeric materials providing possible materials for various applications including biotechnology, nanotechnology, colloid and surface science, materials science, etc . This review summarizes pH-responsive monomers, polymers and their derivative nano- and micro-structures including micelles, cross-linked micelles, microgels and hydrogels.