Development of Computer System for Predicting Phase Diagrams of Associating Polymers

在本研究项目中，我们开发了用于预测缔合聚合物相行为的计算机系统。我们的系统由两部分组成：(1)根据我们最新的缔合聚合物理论，通过数值计算快速得到相图，并将其可视化。(2)用非晶格珠弹簧模型链进行蒙特卡罗模拟，对上述相图中的状态进行结构分析。在第一部分中，我们输入了必要的体系参数，如聚合物的化学物种、它们的聚合度、它们的官能度(官能团的数量，它们在链上的分布)、链的弯曲刚性、缔合常数和相互作用参数。相变的可能性，如宏观和微观相分离、凝胶化、液晶化、胶束化、水化等。我们在相空间中绘制了双节点、旋节点、溶胶/凝胶转变线、微相分离转变线、CMC、向列相和近晶相转变线。在第二部分中，我们用珠-弹簧模型链对相平面上指定的状态进行了蒙特卡罗模拟。聚合物链携带缔合微珠和非缔合微珠。在平衡后，评估了团簇的分布、渗流性质、基本缔合范畴的链集居数等。典型的快照是可视化的。到目前为止，已安装到该计划中的具体体系有：&lt；非凝胶体系&gt；二聚体形成、水化、侧链缔合、氢键液晶&lt；凝胶体系&gt；简单凝胶、多连接凝胶、双组分凝胶、与构象变化耦合的凝胶、氢键液晶网络。

In this research project, we developed computer system for predicting phase behavior of associating polymers. Our system consists of two parts : (1) Fast derivation of phase diagrams by numerical calculation on the basis of our recent theory of associating polymers, and their visualization. (2) Monte Carlo simulation by using off-lattice bead-spring model chains for structural analysis of the state specified on the phase diagrams derived above.In the first part, we input necessary system parameters such as chemical species of polymers, their degree of polymerization, their functionality (number of functional groups, their distribution on a chain), bending rigidity of a chain, association constant, and interaction parameter. Possibility of phase transitions such as macro- and microphase separation, gelation, liquid-crystallization, micellization, hydration, etc. We draw binodals, spinodals, sol/gel transition lines, microphase separation transition lines, CMC, nematic and smectic transition lines in the phase space.In the second part, we carry out Monte Carlo simulation for the state specified on the phase plane by using bead-spring model chains. Polymer chains carry associative beads and non-associative b eads. After equilibriation, distribution of clusters, percolation properties, chain population of fundam ental association categories, etc. are evaluated. Typical snapshots are visualized. Specific systems which have been installed into the program so far are : <Nongelling Systems> Dimer Formation, Hydration, Side-Chain Association, Hydrogen-Bonded Liquid Crystals <Gelling Systems> Simple Gelation, Gelation with Multiple Junctions, 2-Component Gelation, Gelation coupled to Conformational Change, Hydrogen-Bonded Liquid Crystalline Networks