Formation and Dynamics of Self-Organized Structures in Complex Fluids

复杂流体中自组织结构的形成和动力学

基本信息

批准号：
12640371
负责人：
KAWAKATSU Toshihiro
金额：
$ 2.24万
依托单位：
Tohoku University (2001-2003)Nagoya University (2000)
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2003
项目状态：
已结题

项目摘要

In this research, we applied the self-consistent field (SCF) theory, which is a useful tool in theoretical predictions of the spatially inhomogeneous structures in dense polymer systems, to various practical problems. We also extended the self-consistent field theory to dynamical problems.We first checked the validity of the SCF theory by applying it to various problems in dense polymer systems. We studied micellar formation in tri-block copolymer solutions, Change in the surface tension by addition of block copolymers, interactions between polymer-grafted colloidal particles, and so on. We found that changes in the polymer conformation play important roles in interactions between colloidal particles and interfacial properties.Next, we tried to extend the SCF theory to dynamical problems. The simplest way of extending the SCF theory to dynamical problems is to use an assumption of the linear diffusion, i.e. a current of the segments is induced by the gradient of the chemical potential (Ficks law). Using this dynamical SCF theory, we studied a domain formation in thin polymer blend film on a solid surface, and complex domain formations induced by a competition between micro-and macro-phase separations in block copolymer blend. We observed similar phase separation dynamics and domain structures as in realistic systems. We also checked the validity of this dynamical model by comparing it with Rouse model.In a large deformation regime where the chain conformation is considerably deformed by external forces, the above dynamical SCF theory breaks down. In order to evaluate the degree of deformation of the chain conformation, we introduced non-isotropic bond-distribution functions. This new dynamical SCF theory is verified by studying a polymer brush system under shear deformation.

在这项研究中，我们应用了自洽领域（SCF）理论，该理论是密集聚合物系统中空间不均匀结构的理论预测中的有用工具，用于各种实际问题。我们还将自洽场理论扩展到了动态问题。我们首先通过将其应用于密集聚合物系统中的各种问题来检查SCF理论的有效性。我们研究了三块共聚物溶液中的胶束形成，通过添加块共聚物，聚合物接枝的胶体颗粒之间的相互作用等，表面张力的变化等等。我们发现，聚合物构象的变化在胶体颗粒与界面特性之间的相互作用中起着重要作用。我们试图将SCF理论扩展到动力学问题。将SCF理论扩展到动态问题的最简单方法是使用线性扩散的假设，即，段的电流是由化学势梯度（FICKS Law）诱导的。使用这种动力学SCF理论，我们研究了在固体表面上的薄聚合物混合膜中的结构域形成，以及由块共聚物混合物中的微观和宏观分离之间的竞争引起的复杂域的形成。我们观察到与现实系统相似的相分离动力学和域结构。我们还通过将其与Rouse模型进行比较来检查该动力学模型的有效性。在大变形方案中，外部力量链构象大大变形，上述动力学SCF理论分解。为了评估链构象的变形程度，我们引入了非各向同性键 - 分布函数。通过在剪切变形下研究聚合物刷系统来验证这种新的动力学SCF理论。