金属基气凝胶模版剂聚丙烯酸乙醇溶液的分子模拟

Molecular Simulation of Polyacrylic Acid Solutions for Metal- based Aerogels

由于聚丙烯酸是具有长链羧基结构的高聚物,在金属氧化物气凝胶的制备过程中,引入聚丙烯酸作为模版剂,能搭建起气凝胶微观的三维网络结构.运用分子动力学方法构建了分子量分别为800,1800,3000,5000的聚丙烯酸在乙醇溶液模型,同时对在制备实验中运用最广泛的分子量为1800的聚丙烯酸,进行不同浓度下乙醇溶液模型模拟计算.研究溶液模型的回旋半径(Rg),确定了不同模型中聚丙烯酸受到外界条件的影响.同时对径向分布函数g(r)进行了计算,发现聚丙烯酸上的羰基O和聚丙烯酸上的羟基O与乙醇的羟基H有较强的氢键相互作用,还存在有较强的范德华相互作用.综合计算结果,将分子量1800的聚丙烯酸作为金属锌基气凝胶的模版剂,并对其浓度控制在0.11gomL-1是比较合理的.

Due to Polyacrylic acid having the long chain structure with a carboxyl group during the prepara-tion of the metal oxide airgel,introducing the polyacrylic acid as a template agent,to build up the three-dimen-sional network structure of the airgel microstructure is suitable. Molecular dynamics method to build molecular weight 800,1800,3000,5000 polyacrylic acid in ethanol solution model,while the model simulation of the etha-nol solution of different concentrations of polyacrylic acid,the most widely used in the preparation of the experi-ment a molecular weight of 1800,were calculated. That different model polyacrylic acids were affected by external conditions was determined by the radius of gyration（ Rg）of the research solution model. And at the same time, the radial distribution function g（ r）were calculated,finding that carbonyl O and polyacrylic acid on the hydroxyl groups of O and H were interacted,having a strong van der Waals mutual role. Taken together,the results,the molecular weight of 1800 polyacrylic acid as metal copper -based airgel template agent,and its concentration control 0. 11g＆#183;mL-1 is more reasonable.