mireabulletinRussian Technological JournalRussian Technological Journal2782-32102500-316XRTU MIREA10.32362/2500-316X-2017-5-5-25-39mireabulletin-84Research ArticleМИКРО- И НАНОЭЛЕКТРОНИКА. ФИЗИКА КОНДЕНСИРОВАННОГО СОСТОЯНИЯMICRO- AND NANOELECTRONICS. CONDENSED MATTER PHYSICSМЕТОД ЗАТУХАЮЩЕГО ПОТОКА В РЕОЛОГИИ ПОЛИМЕРНЫХ ПОРИСТЫХ ПЛЕНОК, ЗАПОЛНЕННЫХ ЖИДКИМИ КРИСТАЛЛАМИMETHOD OF DECAYING FLOW IN RHEOLOGY OF POLYMERIC POROUS FILMS FILLED BY LIQUID CRYSTALSПасечникС. В.PasechnikS. V.s-p-a-s-m@mail.ruШмелеваД. В.ShmeliovaD. V.noemail@neicon.ruТорчинскаяА. В.TorchinskayaA. V.noemail@neicon.ruСеминаО. А.SeminaO. A.noemail@neicon.ruДюкинА. А.DyukinA. A.noemail@neicon.ruМосковский технологический университет (Физико-технологический институт)РоссияMoscow Technological University (Physico-Technological Institute)Russian Federation201728102017552539Copyright © Пасечник С.В., Шмелева Д.В., Торчинская А.В., Семина О.А., Дюкин А.А., 20172017Пасечник С.В., Шмелева Д.В., Торчинская А.В., Семина О.А., Дюкин А.А.Pasechnik S.V., Shmeliova D.V., Torchinskaya A.V., Semina O.A., Dyukin A.A.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://www.rtj-mirea.ru/jour/article/view/84

Выполнены исследования реологических свойств нематических жидких кристаллов (НЖК) - двухкомпонентной смеси из 2/3 частей р-n-бутил-р-метилоксиазоксибензола и 1/3 части р-n-бутил-р-гептаноилоксиазоксибензола (ЖК-440, МНПО «НИОПИК») и 4-циано-4'-пентилбифенил (5СВ, Merck), заполняющих пористую полимерную (ПЭТФ) матрицу с субмикронными диаметрами пор. С использованием метода затухающего потока Пуазейля установлен ньютоновский характер потока и определены значения эффективных сдвиговых вязкостей НЖК для различных температур. Анализ экспериментальных данных выполнен с учетом влияния эффектов слабого поверхностного сцепления на ориентационную структуру жидких кристаллов. Полученные данные могут быть использованы для расчета рабочих характеристик жидкокристаллических устройств фотоники.

The rheological properties of nematic liquid crystals (NLC) - a two-component mixture of 2/3 parts of p-n-butyl-p-methoxyazoxybenzene and 1/3 parts of p-n-butyl-p-heptanoylazoxybenzene (ZhK-440, NIOPIK) and 4-cyano-4'-pentylbiphenyl (5CB, Merck) filling a porous polymer (PET) matrix with submicron pore diameters are studied. The experiments were fulfilled using the decaying Poiseuille flow arising in a polymer porous film of 23 μm thickness under the action of hydrostatic pressure gradient decreasing with time. In this case a polymer matrix can be considered as a number of cylindrical capillaries connected by a parallel schema. It results in an essential decrease in the hydrodynamic resistance of the system in comparison with the resistance of each capillary. The Newtonian nature of the flow was established, and the effective shear viscosities of NLC for different temperatures were determined. An analysis of the experimental data was carried out taking into account the effect of weak surface anchoring on the orientational structure of the liquid crystals. The data obtained can be used to calculate the technical characteristics of liquid crystal photonic devices.

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The authors declare that there are no conflicts of interest present.