Dual Stimuli‐Responsive Self‐Assembly Behavior of a Tailor‐Made ABC‐Type Amphiphilic Tri‐Block Copolymer

Abstract

This investigation describes the synthesis of a dual stimuli‐responsive, amphiphilic ABC tri‐block copolymer (BCP) based on the functional monomers via RAFT polymerization. In this case, ABC‐type BCP was prepared based on N‐isopropylacrylamide, n‐butyl acrylate, and 4‐vinylpyridine in DMF solvent using cyanomethyl dodecyl trithiocarbonate as the RAFT agent and azobisisobutyronitrile as a thermal initiator in a subsequent macro‐RAFT approach, respectively. The BCPs were characterized by SEC, 1H‐NMR, FTIR spectroscopy, and DSC analyses. Temperature and pH‐dependent properties of the smart BCP micelles in aqueous medium were investigated using dynamic light scattering. Transmission electron microscopic images were taken at cryogenic and dry conditions to study the morphology of molecular assemblies of block copolymers in an aqueous medium. The phase and topographical images were captured by atomic force microscopy to understand the assembly of block copolymers in solvents of different polarities. The morphology of BCP micelles was transformed from flower‐like to spherical in the presence of solvents with different polarities (H2O or CHCl3).

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

“…Incorporation of a small amount of such a highly hydrophobic group in the PVCL network brought down the LCST of PVG copolymer to lower temperature (see SI, Figure S6). Poly­(sulfobetaine) homopolymers (PSB macro-RAFT) with two different molecular weights (5000 and 10000 g/mol) were synthesized by RAFT polymerization as well. 4-Cyano-4-(phenylcarbonothioylthio)­pentanoic acid (CPCPA) was considered as a RAFT agent, as it can effectively polymerize methacrylate monomers with a high chain transfer constant .…”

Latest Advances on the Synthesis of Linear ABC-Type Triblock Terpolymers and Star-Shaped Polymers by RAFT Polymerization

“…Pal et al [ 51 ] published the synthesis of the pH- and thermo- responsive poly ( N -isopropylacrylamide- b -n-butyl acrylate- b -4-vinylpyridine), (PNIPAM- b -PBA- b -P4VP) triblock terpolymers in DMF, with cyanomethyl dodecyl trithiocarbonate as the CTA and azobisisobutyronitrile as the thermal initiator. The self-assembly properties of the terpolymers in aqueous solutions at pH = 3 and pH = 8 were also investigated.…”