Phase diagrams of mixtures of flexible polymers and nematic liquid crystals in a field

نویسندگان

  • Zhiqun Lin
  • Hongdong Zhang
  • Yuliang Yang
چکیده

The Flory-Huggins theory of flexible polymers mixtures @P. J. Flory, Principles of Polymer Chemistry ~Cornell University Press, Ithaca, 1953!# and the Lebwohl-Lasher model of nematogens @G. Lasher, Phys. Rev. A 5, 1350 ~1972!; P. A. Lebwohl and G. Lasher, ibid. 6, 426 ~1972!# are combined to understand the phase behaviors of mixtures of flexible polymers ~coils! and small molecular liquid crystals in an external magnetic field. It is found that, due to the field-induced ordering, the phase boundaries shift upwards and the paranematic spinodal regions are narrowed near the paranematic-nematic transition lines; however, the nematic spinodal regions are enlarged. @S1063-651X~98!13110-0#

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Crystal-liquid crystal binary phase diagrams.

We propose a new theoretical scheme for the binary phase diagrams of crystal-liquid crystal mixtures by a combination of a phase field model of solidification, the Flory-Huggins theory for liquid-liquid mixing and Maier-Saupe-McMillan (FH-MSM) model for nematic and smectic liquid crystal orderings. The phase field theory describes the crystal phase transition of anisotropic organic crystal and/...

متن کامل

Phase diagrams of mixtures of a polymer and a cholesteric liquid crystal under an external field.

We present a mean field theory to describe phase behaviors in mixtures of a polymer and a cholesteric liquid crystal under an external magnetic or electric field. Taking into account a chiral coupling between a polymer and a liquid crystal under the external field, we examine twist-untwist phase transitions and phase separations in the mixtures. It is found that a cholesteric-nematic phase tran...

متن کامل

Investigation into the temperature dependence of isotropic- nematic phase transition of Gay- Berne liquid crystals

Density functional approach was used to study the isotropic- nematic (I-N) transition and calculate the values of freezing parameters of the Gay- Berne liquid crystal model. New direct and pair correlation functions of a molecular fluid with Gay- Berne pair potential were used. These new functions were used in density functional theory as input to calculate the isotropic- nematic transition den...

متن کامل

Phase Separations in Mixtures of a Nanoparticle and a Liquid Crystal

Liquid crystal suspensions including variousmicroand nano-colloidal particles have recently been received great attention for many practical applications such as nanosensors and devices, etc. When large colloidal particles of micronscale are dispersed in a uniform nematic liquid crystal phase, the colloidal particles disturb a long-range orientational order of the nematic phase. For a strong an...

متن کامل

تغییرات ساختاری بلورمایع نماتیک آمیخته به نانوکلوئیدهای مغناطیسی

 The stable colloidal dispersions of magnetic nano-particles in nematic liquid crystals are called ferronematics. Their behaviour in magnetic fields depends on various parameters such as anchoring energy, magnetic anisotropy, and shape and volume fraction of the particles. In the present paper, the threshold field is obtained for these colloidal nematics. Then, the influence of magnetic anisotr...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 1998