Key Laboratory for Ultrafine Materials of Ministry of Education, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237, China
Abstract:
The lattice theory regarding ternary systems involving a conformationally variable polypeptide and a randomly coiled polymer presented recently is extended to the case where an external orientational field is present. Chemical potentials of the components in the isotropic and anisotropic phases were obtained. The calculations carried out show that the external field exerts a marked effect on the phase behavior of the ternary systems. The isotropic-anisotropic biphasic gap is predicted to shift to lower polymer concentrations and become narrower when the external field exists. The entrance of the randomly coiled polymers into the anisotropic phase is promoted. Influences of chain conformation of polypeptide, chain length and temperature have been studied in the presence of the external field. The comparison between theory and experimental results was also carried out.
