Description
Methylcellulose is a thermoresponsive polymer that undergoes a morphological transition at elevated
temperature, forming uniform diameter fibrils. However, the gelation mechanism is still unclear, in particular,
at higher polymer concentrations. We use Langevin dynamics simulations to investigate a coarse-grained model
for methylcellulose that produces collapsed ringlike structures in dilute solution with a radius close to the fibrils
observed in experiments. We show that the competition between the dihedral potential and self-attraction causes
these collapsed states to undergo a rapid conformational change, which helps the chain to avoid kinetic traps by
permitting a transition between collapsed states. If the dihedral potential is removed, the chains do not escape
from their collapsed configuration, whereas at high dihedral potentials, the chains cannot stabilize the collapsed
state. We provide systematic data on the effect of the dihedral potential in a model of methylcellulose, and discuss
the implication of these previously overlooked rapid conformational fluctuations on the spontaneous formation
of high-aspect-ratio fibrils.
temperature, forming uniform diameter fibrils. However, the gelation mechanism is still unclear, in particular,
at higher polymer concentrations. We use Langevin dynamics simulations to investigate a coarse-grained model
for methylcellulose that produces collapsed ringlike structures in dilute solution with a radius close to the fibrils
observed in experiments. We show that the competition between the dihedral potential and self-attraction causes
these collapsed states to undergo a rapid conformational change, which helps the chain to avoid kinetic traps by
permitting a transition between collapsed states. If the dihedral potential is removed, the chains do not escape
from their collapsed configuration, whereas at high dihedral potentials, the chains cannot stabilize the collapsed
state. We provide systematic data on the effect of the dihedral potential in a model of methylcellulose, and discuss
the implication of these previously overlooked rapid conformational fluctuations on the spontaneous formation
of high-aspect-ratio fibrils.
| Date made available | 2017 |
|---|---|
| Publisher | Data Repository for the University of Minnesota |