Kazuhiro Ishida, Takahiro Uno, Takahito Itoh, and Masataka Kubo
The authors prepared a mechanically cross-linked gel using a cyclic PEG
macromer co polymerized with NIPAAm. The pNIPAAm chain sections can
thread through the PEG cycles, creating movable physical cross-links.
Gels were characterized by swelling kinetics and compared to gels made
of a linear PEG macromer copolymerized with pNIPAAm using bisacrylamide
as a chemical crosslinker. The cycle-containing gels showed
significantly higher swelling compared to gels containing the same
amount of PEG in linear form. The authors attribute this to the movable
nature of the threaded cross-links.