Premium
Hydrophilic–Hydrophobic‐Transition‐Triggered Thermosensitive Macroscopic Gel Assembly
Author(s) -
Peng Yan,
Wang ZongChun,
Xu XiaoDing,
Song JinChun
Publication year - 2013
Publication title -
macromolecular chemistry and physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.57
H-Index - 112
eISSN - 1521-3935
pISSN - 1022-1352
DOI - 10.1002/macp.201300445
Subject(s) - lower critical solution temperature , self healing hydrogels , self assembly , poly(n isopropylacrylamide) , hydrophobic effect , cyclodextrin , polymer chemistry , chemical engineering , chemistry , transition temperature , materials science , nanotechnology , polymer , copolymer , organic chemistry , superconductivity , physics , quantum mechanics , engineering
Two kinds of poly( N ‐isopropylacrylamide) (PNIPAAm)‐based hydrogels containing β‐cyclodextrin (β‐CD) (host gel) and benzyl (guest gel) groups, respectively, are designed and prepared. When mixing the host and guest gels together, due to the presence of the host–guest interaction between the β‐CD and benzyl groups, a combined hydrogel can be formed at a temperature below the lower critical solution temperature (LCST) via macroscopic self‐assembly. When heating this self‐assembling system to a temperature above the LCST, the aggregation of the hydrophobic PNIPAAm‐based chains pull the β‐CD and benzyl groups to separate them from each other, leading to the disassociation of the combined hydrogel. Because of the transition from hydrophobic aggregated PNIPAAm‐based chains to hydrophilic extended ones as the temperature decreases to a value below LCST, the combined hydrogel can re‐form via macroscopic self‐assembly between the host and guest gels. The concept of hydrophilic–hydrophobic transition‐triggered thermosensitive macroscopic self‐assembly can be extended to develop many other stimuli‐responsive materials.