电场作用下二元高分子共混体系微观组织演化的相场模拟
Phase-field simulation of microstructure evolution in binary polymer blends under electric fields
邢文琪 1覃众垚 1郭建超 1张刚1
作者信息
- 1. 宝鸡文理学院 物理与光电技术学院,陕西 宝鸡 721016
- 折叠
摘要
高分子复合材料具有单个高分子材料所不具备的优异性能.为探究电场作用下二元高分子共混体系微观组织演化及动力学过程,基于形貌和各向异性参数,采用相场法进行了数值模拟.采用高精度的半隐式傅立叶谱法,求解修改的非线性Cahn-Hilliard-Cook(CHC)扩散方程.模拟结果表明,外加电场对高分子共混体系相分离的微观组织及动力学过程有着显著影响.在外加电场作用下,随着时间进行,各向异性参数逐渐增大,最终达到稳定,并且电场越强,各向异性参数的初始值越大.此外,体系的初始成分对电场取向的动力学过程影响显著,尤其对具有临界成分的体系,电场的取向作用更强且更显著.最后,研究揭示了电场对高分子共混物相分离过程的作用机理.研究结论有助于设计并指导合成具有各向异性微观结构及优异性能的高分子复合材料.
Abstract
Polymer composites exhibit superior properties that are absent in individual polymeric materials.To investigate the microstructural evolution and kinetic processes of binary polymer blends under electric fields(E-fields),numerical simulation based on the morphology and anisotropy parameter was carried out by a phase-field method.The modified nonlinear Cahn-Hilliard-Cook(CHC)diffusion equation was numerically solved by adopting high-accuracy semi-implicit Fourier spectral method.The simulated results show that the application of E-field remarkedly affects the phase-separating structure and kinetic process of polymer blends.Under the applied E-fields,the anisotropy parameter gradually increases with time and then reaches to an equilibrium,and stronger E-field leads to larger initial values of anisotropy parameter.In addition,the effect of initial composition on the orientation kinetics of E-field is significant and for the system with the critical composition,the orientation kinetic process is faster and stronger than the system with an off-critical composition.This study reveals the mechanism of E-field action on the polymer blend undergoing phase separation.Meanwhile,it can be used as a theoretical basis to design and guide the synthesis of polymer composites with anisotropic microstructures and superior properties.
关键词
电场/二元高分子共混体系/相分离/相场模拟/微观组织Key words
electric field/binary polymer blends/phase separation/phase-field simulation/microstructure引用本文复制引用
出版年
2024
国家科技期刊平台
NSTL
万方数据