6533b827fe1ef96bd1285b54

RESEARCH PRODUCT

Blends of Semiflexible Polymers: Interplay of Nematic Order and Phase Separation

Arash NikoubashmanKurt BinderAndrey MilchevSergei A. EgorovJiarul Midya

subject

nematic orderMaterials sciencePolymers and PlasticsTriple pointThermodynamicsOrganic chemistry02 engineering and technology01 natural sciencesArticleliquid crystalsQD241-441Critical point (thermodynamics)Liquid crystalsemiflexible polymersPhase (matter)0103 physical sciencesLyotropicphase behaviormacromolecules010306 general physicsdensity functional theoryPhase diagramPersistence lengthGeneral Chemistry021001 nanoscience & nanotechnologymolecular dynamicsCondensed Matter::Soft Condensed MattermixturesBending stiffnessddc:540blends0210 nano-technology

description

Mixtures of semiflexible polymers with a mismatch in either their persistence lengths or their contour lengths are studied by Density Functional Theory and Molecular Dynamics simulation. Considering lyotropic solutions under good solvent conditions, the mole fraction and pressure is systematically varied for several cases of bending stiffness κ (the normalized persistence length) and chain length N. For binary mixtures with different chain length (i.e., NA=16, NB=32 or 64) but the same stiffness, isotropic-nematic phase coexistence is studied. For mixtures with the same chain length (N=32) and large stiffness disparity (κB/κA=4.9 to 8), both isotropic-nematic and nematic-nematic unmixing occur. It is found that the phase diagrams may exhibit a triple point or a nematic-nematic critical point, and that coexisting phases differ appreciably in their monomer densities. The properties of the two types of chains (nematic order parameters, chain radii, etc.) in the various phases are studied in detail, and predictions on the (anisotropic) critical behavior near the critical point of nematic-nematic unmixing are made.

yearjournalcountryeditionlanguage
2021-07-01
10.3390/polym13142270