TY - JOUR
T1 - Conformation and ionization behavior of charge-regulating polyelectrolyte brushes in a poor solvent
AU - Yuan, Jiaxing
AU - Wang, Yanwei
PY - 2021/9/8
Y1 - 2021/9/8
N2 - Understanding the structural response of weak polyelectrolyte brushes upon external stimuli is crucial for their applications ranging from modifying surface properties to the development of smart and intelligent materials. In this work, coarse-grained molecular dynamics simulations were carried out to investigate the conformation and ionization behavior of charge-regulating polyelectrolyte brushes in poor solvent conditions, using an implicit solvent model. The results show that, while the thickness of a sparse polyelectrolyte brush shows a similar behavior as that of a single chain, namely a monotonic change as a function of solvent quality (modeled by an effective segment-segment attraction strength parameter) and solution pH, dense polyelectrolyte brush exhibits more complex behavior. An unexpected re-expansion is observed when the effective segment-segment attraction strength is further increased, especially in the case of high pH. In the latter case, strong attraction in polymer segments promotes the formation of large, inter-chain, cylindrical aggregates, leading to an increase in brush thickness.
AB - Understanding the structural response of weak polyelectrolyte brushes upon external stimuli is crucial for their applications ranging from modifying surface properties to the development of smart and intelligent materials. In this work, coarse-grained molecular dynamics simulations were carried out to investigate the conformation and ionization behavior of charge-regulating polyelectrolyte brushes in poor solvent conditions, using an implicit solvent model. The results show that, while the thickness of a sparse polyelectrolyte brush shows a similar behavior as that of a single chain, namely a monotonic change as a function of solvent quality (modeled by an effective segment-segment attraction strength parameter) and solution pH, dense polyelectrolyte brush exhibits more complex behavior. An unexpected re-expansion is observed when the effective segment-segment attraction strength is further increased, especially in the case of high pH. In the latter case, strong attraction in polymer segments promotes the formation of large, inter-chain, cylindrical aggregates, leading to an increase in brush thickness.
U2 - https://doi.org/10.1021/acs.jpcb.1c04451
DO - https://doi.org/10.1021/acs.jpcb.1c04451
M3 - Article
SN - 1520-6106
VL - 125
SP - 10589
EP - 10596
JO - Journal of Physical Chemistry B
JF - Journal of Physical Chemistry B
IS - 37
ER -