大分子蠕动的Monte Carlo模型及计算方法

高分子链分子量巨大而且分散,结构复杂多变,存在大量不确定的问题,给理论和实验研究造成许多困难。本文建立了一种基于高分子Monte Carlo模拟算法,分析分子蠕动阻力的模型。用链动力学法构造8配位点键长涨落格子链多链体系,通过高分子链的运动使任意的初始有序态演化到平衡态,可同时获得体系的动态和静态性质。将重要性抽样法和高分子多链体系的链动力学构造法,在键长涨落模型中结合起来,形成多链体系的链动力学求解法。引入空格扩散算法,用以研究高浓度态的高分子体系。统计平衡后元胞内高分子多链体系在链动力学算法作用下蠕动失败机率,对高聚物多链体系内分子蠕动的困难程度的定量模拟,能更直观分析高分子玻璃化转变的现象。

A practical method of Monte Carlo simulation and calculation for macromolecule vermiculation

Macromolecule chain has huge molecular weight which is distributed in a large range,its structure is complex and variable, and there exist a lot of uncertainties.This makes the theoretical and experimental study more difficult.In this paper,a simulation mod- el is proposed to analyze molecule vermiculation resistance,based on the macromolecule Monte Carlo simulation strategy.A multi- chain system of the grid chain of band-length fluctuation with 8 coordination points is constructed by means of chain dynamic method. Through the movement of macromolecule chain,an arbitrary initial ordered state is evolved to an unorderod state,and both dynamic and static properties can be obtained.The chain dynamics solving method of the multi-chain system is developed by combining the method of importance sampling and the one of chain dynamics construction of the macromolecule multi-chain system in the chain-length Fluctuation model.The space diffusion algorithm is used to study the macromolecule system in high concentration state.Through the statistics of the vermiculation failure probability of the macromolecule multi-chain system in unit cell after equilibrium,a quantitive sim- ulation can be conducted for the molecule vermiculation resistance in the macromolecule multi-chain system,and the glass transition of macromolecule systems can be analyzed more directly.