Nematic-isotropic interfaces in semiflexible polymer blends

Abstract

We present calculations of the anisotropy of the tension of interfaces separating an isotropic phase rich in a flexible polymer from a nematic phase rich in a semiflexible polymer. We find that the interfacial tension is always lower when the director is parallel to the plane of the interface than when it is perpendicular. The ratio of the tension in the perpendicular to parallel case can be quite large, of order 5 or so, depending on the strength of the nematic interactions. We also find that the interfacial width is always lower in the parallel case even though the tension is lower; this is because the orientational density prefers parallel alignment of chains at the interface.

Nematic-amorphous polymer interfaces in the presence of a compatibilizer

“…At ϭ200, the length of the dashes in the center of the B 5 n domain is more uniform, while nematic ordering is strongest at the interface. 22 In order to get a quantitative measure of the interfacial width as a function of the orientational order we fitted a function to the B -density profiles. 3 for time ϭ10, 200.…”

“…22 In order to test the simulation against this prediction two systems are compared: the A 8 22 In order to test the simulation against this prediction two systems are compared: the A 8…”

“…The reduction of the interfacial width by the presence of the nematic segments is in accord with the predictions of Drovetsky et al 22 for three-dimensional ͑3D͒ systems. The order of magnitude of these values is in agreement with general expectations which predict that the interfacial width should be of the order of d/hϭO(a/ͱ/kT) ͑Ref.…”

A study on interfacial tension between flexible polymer and liquid crystal

“…Nevertheless, the anchoring at a nematic-isotropic interface is a matter of some debate [8]. Doi et al [19] and Drovetsky et al [20] predicted director orientation parallel to the interface, while Doerr et al [21] and Li et al [4] revealed a homeotropic orientation to interface by simulations. Wu et al [8] recently examined the nematic orientation at the LCP and PDMS interface experimentally, with a developed automated compensation technique polarizing optical microscope, and the results also show the homeotropic orientation at the interface.…”

Semiflexible polymer solutions. I. Phase behavior and single-chain statistics

“…The advantage of the Liu-Fredrickson theory is that it is analytical and convenient for treating inhomogeneous systems. 23 However, its accuracy for describing the nematic state is a priori not clear, given the strongly first-order nature of the isotropic-nematic transition. Furthermore, the order parameter expansion uses chain statistics in the isotropic state and thus cannot describe the chain conformation properties in the nematic state.…”