Molecular Dynamics Simulation Of Betaine Surfactant Solution Properties

In this graduation design is based on molecular dynamics as a research tool, themicroscopic study on the zwitterionic betaine surfactant solution in nature.This article first surfactant in the oil-water interface, the nature of a simulation study toclarify the surfactant structure and interfacial tension relationship, which is a surfactantsolution of the internal mechanism of experimental study of a strong complement to thesimulation results show that the stress tensor method oil-water interfacial tension valuesobtained with the experimental values with simulation credible, you can compare differentqualitative structure of surfactant molecules in aqueous solution interfacial tension. ZSBm-nseries surfactants reduce the oil-water interfacial tension with good ability, with positive andnegative charge and aromatic groups increased the number of inter-ethylene, the active agentreduces the ability of oil-water interfacial tension decreased by orders of magnitude, trend isclearly.This article also for the surfactants on the temperature and salt-resistant performancesimulation, expectations for the design of flooding enhanced oil recovery in the formulationand effective application of surfactant to provide a theoretical basis and guidance. Simulationresults show that, ZSBm-n series surfactants with good temperature, salt performance, sixkinds of betaine-type zwitterionic surfactant molecules ZSB9-1temperature salt bestperformance.This article also for the thermodynamic properties of surfactant did some research andcame to the enthalpy entropy compensation information. Simulation results show that betainesurfactant micelles in aqueous solutions of a spontaneous process, entropy plays a dominantrole in driving force; but with the temperature, entropy change of Gibbs free energycontribution to the downward trend enthalpy contribution trend has increased. Betainesurfactant micelles in aqueous solution there is the process of enthalpy-entropycompensation phenomenon, the compensation temperature (308.5±0.5) K, with positive andnegative charge and aromatic groups between the increase in the number of ethylene to formability and stability of the micelles were increased.