Self-consistent Field Simulation Of Self-assembled Micelles In Rod-coil Polymer Systems

A block copolymer is a special type of polymer obtained by chemically bonding two or more kinds of blocks whose monomers are chemically identical.A rod-coil polymer is a two-block copolymer in which a rigid molecular segment has anisotropy and orientation order.The amphiphilic block copolymers can self-assemble in solution to form specific ordered micelles(layered,columnar,globular,vesicular).Due to its rich structural properties and attractive application prospects,the study of block copolymer self-assembled micelles has become an important topic in the fields of polymer physics,chemistry and materials.An important means to study the structural properties of polymer self-assembled micelles is the self-consistent mean field theory.The core idea is to transform a multibody system into a monomer system under the equivalent external field,and turn the particle-based system into a field-based system.Therefore,the problem of solving the equilibrium state of the polymer system is transformed into a mathematical problem for solving the corresponding self-consistent field equations.The main work of this paper is to study the morphological transformation of the self-assembled micelle structure of rodcoil/coil and the main physical parameters has an effect on micelles by the self-consistent field numerical simulation method under the grand canonical ensemble.Numerical results show that the structure of micelle will change when the volume fraction of block A increases.such as,when f_A= 0.58,the lamellar micelle will be transformed into a cylindrical micelle,when f_A= 0.68,the cylindrical micelle will turn into a spherical micelle.Finally,the hardness of polymer chain,long range force and some asymmetric parameters of polymer chain have an effect on the structural transformation of different micelles.As these factors increase,the core radius of both spherical and cylindrical micelles will increases,and shell thickness of both spherical and cylindrical micelles will decreases,which lead to the variation of the micelle structure.