Characteristics of zwitterionic sulfobetaine acrylamide polymer and the hydrogels prepared by free-radical polymerization and effects of physical and chemical crosslinks on the UCST

One-pot synthesis of responsive sulfobetaine nanoparticles by RAFT polymerisation: the effect of branching on the UCST cloud point

“…Their work differs from the work discussed here as they studied 95 hydrogels rather than discreet branched particles, however the results support the results reported in our work. 36 Inspired by recent work by Weaver et. al.…”

“…36 Here it is proposed that the homopolymer of PDMAPS forms a core-shell structure in 70 response to decreased temperature, with the shorter chains of PDMAPS solubilising the branched core in solution. At elevated temperatures the core swells, but the branching groups constrain the polymer structure, resulting in a particle collapse upon response to decreased temperature rather than macroscopic 75 precipitation ( Figure 5).…”

Switchable Materials Containing Polyzwitterion Moieties

“…Thermoresponsive copolymers containing a combination of the sulfobetaine monomer and monomers such as NIPAM [88,89] or VCL [82] can vary their UCST as well as LCST.…”

Changes in the Properties and Self‐Healing Behaviors of Zwitterionic Nanocomposite Gels Across Their UCST Transition

“…The zwitterionic sulfobetaine monomer, N,Ndimethyl(acrylamidopropyl) ammonium propanesulfonate (A 3 ), was synthesized as previously described in the literature, [20] similar to how Lee et al [26] and Seubert et al [27] synthesized it. The synthesis procedure is shown in Scheme 1a.…”

“…[10,18,19] Sulfobetaine polymers with a cationic quaternary ammonium group (N þ R 4 ) and an anionic sulfonate group (SO 3 À ) in the side chain adopt expanded conformations in water (transparent solutions) at temperatures higher than the UCST, while the polymer conformation collapses (turbid solution) at temperature below the UCST. In our previous paper, [20] we reported the molecular characteristics and property relationships for sulfobetaine acrylamide polymers and their physically and chemically crosslinked hydrogels. It was found that a sulfobetaine polymer and its hydrogels synthesized by free-radical polymerization of N,N-dimethyl(acrylamidopropyl) ammonium propane sulfonate (A 3 ) monomer in an aqueous redox system exhibits a welldefined UCST-type phase transition, and the UCST could be controlled over a wide range by varying the polymer concentration (C p ) and molecular weight.…”