玻璃钢与含CO2流体界面模型与MS模拟

在CO2驱油项目中，由于CO2是以超临界状态与水交替注入井下，局部形成了具有腐蚀性的CO2和水的混合物.为研究玻璃钢(GFRP)与这种混合物的界面间相互作用，本文采用Material Studio(MS)模拟软件建立了环氧树脂与链烃、水、CO2、H2CO3 4种纯净物流体之间的界面模型，以及树脂与链烃/水/CO2、链烃/H2CO3 2种混合流体间的界面模型，并通过分子动力学计算得到了6种界面模型的最低能量结构和界面能.结果表明,链烃与树脂界面几乎不吸附，CO2、水与树脂界面吸附较差，H2CO3与树脂界面能较高，能与树脂中的—NH2、—OH基团形成氢键具有较好的吸附作用，即H2CO3是混合体系中与环氧树脂作用的主要物质.
It is significant to focus on the corrosion of GFRP in CO2 flooding project because the corrosive mixture of CO2 and water are formed when CO2 is injected underground alternatively with water at supercritical state. The interfacial models between GFRP and hydrocarbon, H2O, CO2, H2CO3, hydrocarbons/H2O/CO2 and hydrocarbons/H2CO3 were established by Material Studio to investigate the effects of interface . The interfacial energy and minimum energy structure for six kinds of interface models are obtained through the molecular dynamics simulation. The results show that the hydrocarbon is merely adsorbed by epoxy resin, and CO2 and H2O are absorbed at very limited level, respectively. However the adsorption between the resin and H2CO3 is remarkable compared with other fluent, and hydrogen bond was formed between —NH2 and —OH. It can be deduced that the H2CO3 is the main substance act with amine cured GFRP in the mixture.