摘要
通过介观动力学方法(MesoDyn)研究了低浓度下的三嵌段共聚物PEO27PPO61PEO27(P104)水溶液的聚集行为,讨论了聚合物浓度、模拟时间对P104水溶液相行为的影响.在聚合物浓度较低(φ<35%)的情况下,可以形成三种不同的胶束聚集体:球形胶束(sphericalmicelle)、胶束簇(micellarcluster)和盘状胶束(disk-likemicelle).(1)球形胶束(5%-10%,φ),模拟的胶束结构表明疏水的PPO嵌段形成球形内核(micellarcore),而亲水的PEO嵌段形成核壳(micellarcorona),并有水分子存在内核和核壳之中;(2)胶束簇(11%-15%,φ),由于球形胶束之间的缔合,形成直径明显高于球形胶束的聚集体,其半径比球形胶束大1nm左右;(3)盘状胶束(16%-25%,φ),胶束簇核壳PEO嵌段之间的相互缠绕,形成了成串的类似盘状的胶束.模拟中有序参数随浓度的变化证明了这种结构划分的合理性.
The microphase separation dynamics of triblock copolymer surfactant [（ethylene oxide）27（propylene oxide）61- （ethylene oxide）27]（P104） in aqueous solution .was simulated by a dynamic variant of mean-field density functional theory for Gaussian chains. Different morphologies depending on the simulation concentration and time were shown in low concentration （φ〈35%）. With the increase of the concentration, the self-assemble aggregates changed from spherical micelles, micellar clusters, to disk-like micelles. （1） In the spherical micellar region （5%-10%, φ）, the result of the simulation was similar to that of the experiment in that micelle was a dense core consisting mainly of PPO and a hydrated PEO swollen corona. （2） Due to the coalescence among spherical micelles, larger micellar clusters are formed in a concentration ranging from 11% to 15%（φ）. （3） Owing to the attractions between the PEO coronas of micellar clusters, series of disk-like micelles were found above the concentration 16%（φ）. The order parameters showed that the phase separation of spherical micelles was easily formed, while the micellar cluster or disk-like micelles required a longer time to acquire steady equilibrium.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2007年第2期139-144,共6页
Acta Physico-Chimica Sinica
基金
国家自然科学基金(20303011)资助项目
关键词
嵌段共聚物
介观模拟
胶束
Block copolymer
Mesoscopic simulation
Micelle
