Stimuli-Responsive Block Copolymer Micelles Based on Mussel-Inspired Metal-Coordinated Supramolecular Networks.

Amphiphilic diblock copolymers containing dopamine and zwitterions are synthesized via the RAFT polymerization method, which undergo temperature-mediated micellization in aqueous media. The presence of catechol moiety in dopamine is exploited to form pH-responsive cross-links with ferric ions (Fe ) at different pH value. Herein, a comprehensive study of the effect of pH as well as temperature on the size and solution behavior of these cross-linked micelles is presented.

Zwitterionic Nanogels and Microgels: An Overview on Their Synthesis and Applications.

Zwitterionic polymers by virtue of their unique chemical and physical attributes have attracted researchers in recent years. The simultaneous presence of positive and negative charges in the same repeat unit renders them of various interesting properties such as superhydrophilicity, which has significantly broadened their scope for being used in different applications. Among polyzwitterions of different architectures, micro- and/or nano-gels have started receiving attention only until recently.

A dual thermoresponsive and antifouling zwitterionic microgel with pH triggered fluorescent "on-off" core.

A unique, tailor-made, zwitterionic, dual thermoresponsive and fluorescent microgel probe was synthesized via Reversible Addition Fragmentation chain-Transfer (RAFT) polymerization. Microgels were prepared via oil in water (o/w) emulsion polymerization where poly(carboxybetaine) (PCB) acted as a macro-RAFT reagent as well as an emulsifier. The presence of poly(N-vinylcaprolactam) (PNVCL) in the microgel system imparts the thermoresponsiveness to the system and the presence of a rhodamine derivative as fluorophore makes it responsive to pH change of the system by showing a fluorescence emission at 580 nm (reddish orange color).

Stimuli-Responsive Zwitterionic Core-Shell Microgels for Antifouling Surface Coatings.

Fouling on filtration membranes is induced by the nonspecific interactions between the membrane surface and the foulants, and effectively hinders their efficient use in various applications. Here, we established a facile method for the coating of membrane surface with a dual stimuli-responsive antifouling microgel system enriched with a high polyzwitterion content. Different poly(sulfobetaine) (PSB) zwitterionic polymers with defined molecular weights and narrow dispersities were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization and integrated onto poly(-vinylcaprolactam) (PVCL) microgels via a controlled dosage of a cross-linker, adapting a precipitation polymerization technique to obtain a core-shell microstructure.

Dual-Temperature-Responsive Microgels from a Zwitterionic Functional Graft Copolymer with Superior Protein Repelling Property.

In this work, we developed a synthetic strategy to synthesize dual-temperature-responsive low surface fouling zwitterionic microgels. Statistical poly(-vinylcaprolactam--glycidyl methacrylate) copolymers were synthesized by RAFT polymerization and post-modified by thiol-epoxy click reaction with thiol end-group-modified poly(sulfobetaine) macro-RAFT (PSB-SH) to obtain poly(-vinylcaprolactam--glycidyl methacrylate)--poly(sulfobetaine) (PVCL--PGMA--PSB) graft copolymers. Synthesized graft copolymers were cross-linked by diamine cross-linker in water-in-oil (w/o) inverse mini-emulsion to obtain zwitterionic microgels.