水溶性高分子弱凝胶体系凝胶化过程的Monte Carlo模拟

为研究弱凝胶的形成过程,并把高分子弱凝胶用于三次采油,采用三维Monte Carlo模拟了高分子溶液凝胶化过程. 模拟预测了凝胶化开始的时间,得到了凝胶化过程中分子量分布的演化规律和胶团生长的三维图像. 发现生成溶胶与凝胶团的歧化过程,初始聚合物的浓度对能否形成凝胶至关重要,低于临界浓度不能形成凝胶. 模拟了凝胶化速度和聚合物浓度以及交联剂浓度的关系,并与粘度随凝胶化时间变化的实验结果进行比较, 结果表明， 聚合物浓度较高时,浓度对交联反应的影响减弱,这一趋势与实验结果相一致.

Monte Carlo Simulation of the Gelation Process of the Aqueous Polymer Weak Gel

To study the gelation process of weak gel and apply weak gel for the industrial practice of tertiary oil recovery, three dimensional Monte Carlo simulations were carried out to obtain the growth of average molecular weights and gel growth images. It is found that the initial polymer concentration is critical for the gel formation. The dismutation process of sol-gel groups is clearly observed. The relationship between the speed of gelation and the concentration of crosslink agent was also simulated. The predicted dependency of the gel time upon the concentration of crosslink agent is in good agreement with the experimental data of viscosity versus time. Also, the polymer concentration effects agree well with viscosity data. The simulation correctly predicts that the concentration effect on crosslink reaction will be weaker at the higher polymer concentration.