文献类型：期刊文献

中文题名：H_(2)O在PBT聚醚聚氨酯弹性体渗透行为的分子模拟

英文题名：Molecular Simulation of Permeation Behavior of H_(2)O in PBT Polyether Polyurethane Elastomer

作者：杨敏[1];王卫泽[1];苏雅琪[1];轩福贞[1]

机构：[1]华东理工大学机械与动力工程学院,上海200237

年份：2023

卷号：49

期号：1

起止页码：34

中文期刊名：华东理工大学学报（自然科学版）

外文期刊名：Journal of East China University of Science and Technology

收录：Scopus;北大核心:【北大核心2020】；CSCD:【CSCD_E2023_2024】；

语种：中文

中文关键词：PBT推进剂;分子动力学;吸附;扩散;模拟;渗透

外文关键词：PBT propellant;molecular dynamics;adsorption;diffusion;simulation;permeation

摘要：采用蒙特卡洛模拟和分子动力学模拟的方法,对H_(2)O在3,3-双(叠氮甲基)环氧乙烷-四氢呋喃共聚醚(PBT)聚醚聚氨酯(PUPBT)中的吸附和扩散行为进行模拟。吸附模拟结果表明,在0~1 000 kPa逸度范围内,298、318、338、358 K条件下的PUPBT对H_(2)O的吸附热分别为41.15、40.23、36.84、34.16 kJ/mol,298 K下达到吸附平衡,随着温度的升高,PUPBT对H_(2)O的吸附能力减弱;H_(2)O在PUPBT中的吸附不是均匀吸附,而是聚集性地吸附于聚合物中靠近空穴中心的低势能区。扩散模拟结果表明,在压强为101 kPa,温度为298、318、338、358 K条件下,H_(2)O/PUPBT混合体系的自由体积分数分别为14.37%、 15.55%、 17.00%、 17.85%,H_(2)O在PUPBT中的扩散系数分别为1.488×10^(-6)、1.999×10^(-6)、4.086×10^(-6)、4.462×10^(-6)cm^(2)/s,且H_(2)O在PUPBT中进行的扩散不是均匀扩散,而是在聚合物空穴之间的跃迁扩散。H_(2)O在PUPBT中的溶解系数是影响渗透系数的主要因素,随着温度的升高,渗透系数逐渐下降。
Based on the method of Grand Canonical Monte Carlo and molecular dynamic simulation, the adsorption, diffusion and permeation behavior of H_(2)O in PBT polyether polyurethane(PUPBT) elastomer were simulated. The results show that the heat of adsorption of H_(2)O on PUPBTat 298, 318, 338, 358 K is 41.15, 40.23, 36.84,34.16 kJ/mol, respectively, in the fugacity range of 0~1 000 kPa. The adsorption equilibrium has been reached when the temperature is 298 K. With the increase of temperature, the adsorption capacity of PUPBTtoward H_(2)O is declined. The adsorption of H_(2)O on PUPBTis not a uniform adsorption, H_(2)O molecules are adsorbed to the lower potential energy region near the center of the holes in the polymer. When the pressure is 101 kPa, the free volume fractions of H_(2)O/PUPBTare 14.37%, 15.55%, 17.00% and 17.85%, and the diffusion coefficients of H_(2)O into PUPBTare 1.488×10^(-6),1.999×10^(-6), 4.086×10^(-6) and 4.462×10^(-6) cm^(2)/s, respectively, at the temperature of 298, 318, 338, 358 K. And the diffusion of H_(2)O into PUPBTis not a uniform diffusion, but a jump-motion diffusion in free volumes. The solubility coefficient of H_(2)O molecules in PUPBTis the major factor that affects the permeability coefficient of the system. With the increase of temperature, the permeability coefficient of H_(2)O into PUPBTdecreases gradually.