10.1021/acsmacrolett.7b00557.s001
Sebastian Backes
Sebastian
Backes
Patrick Krause
Patrick
Krause
Weronika Tabaka
Weronika
Tabaka
Marcus U. Witt
Marcus U.
Witt
Debashish Mukherji
Debashish
Mukherji
Kurt Kremer
Kurt
Kremer
Regine von Klitzing
Regine von
Klitzing
Poly(<i>N</i>‑isopropylacrylamide)
Microgels under Alcoholic Intoxication: When a LCST Polymer Shows
Swelling with Increasing Temperature
American Chemical Society
2017
bulk solution properties
VPTT
volume phase transition temperature
LCST Polymer Shows
isopropylacrylamide
PNIPAM microgels
reswelling
2017-09-12 12:50:48
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Poly_i_N_i_isopropylacrylamide_Microgels_under_Alcoholic_Intoxication_When_a_LCST_Polymer_Shows_Swelling_with_Increasing_Temperature/5398423
Poly(<i>N</i>-isopropylacrylamide)
(PNIPAM) microgel
is a smart polymer that shows a volume phase transition temperature
(VPTT) at around 32 °C in aqueous solutions, above which it collapses.
In this work, combining experiments and molecular simulations, it
is shown that PNIPAM microgels do not always exhibit a collapsed structure
above the VPTT. Instead, PNIPAM in aqueous alcohol mixtures shows
a two-step conformational transition, i.e., a collapse at low temperatures
(<i>T</i> < 32 °C) and a reswelling when <i>T</i> > 50 °C. The present analysis indicates that delicate
microscopic interaction details, together with the bulk solution properties,
play a key role in dictating the reswelling behavior. Even when PNIPAM
microgels swell with increasing <i>T</i>, this is not a
standard upper critical solution behavior.