(78i) Shifting Isotropic-Nematic Transition in Strongly Confined Semi-Flexible Polymer Solutions
AIChE Annual Meeting
Monday, November 14, 2016 - 10:08am to 10:24am
We investigated the phase behavior of semi-flexible polymer
solutions under sub-persistence length slit confinement of height H.
Strong confinement leads to increased intra-polymer segmental
correlation length (l//)
in the unconfined dimensions that could reach up to twice the polymer
persistence length P. The increased
l// results in better
alignment of segments and shifts the isotropic-nematic transition density fIN. We found that in unconfined systems (H >> P), the dependence of fIN on P follows Onsager theory predictions. Enhanced segmental alignment
is also observed near walls. For strongly confined polymer solutions, fIN
decreases as H decreases due to the
increased segmental correlation length, and enhanced segmental alignment is
found throughout the solution.
Qualitative agreements with mean-field theory are found. The shift in fIN also affects
the confined polymer solution dynamics.