Matière et Systèmes Complexes, UMR 7057 CNRS and Université Paris Diderot, 10 rue Alice Domon et Léonie Duquet, 75205 Paris Cedex 13, France.
Langmuir. 2010 Sep 21;26(18):14430-6. doi: 10.1021/la102744c.
Small-angle neutron scattering and thermorheology techniques are used to investigate in detail the effect of laponite particles in aqueous solutions of poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide), PEO-PPO-PEO, block copolymers in the concentrated regime. At high polymer concentration or temperature, the micellar solutions exhibit a phase transition from fluid to crystal due to crowding of the micelles. The addition of laponite is found to disturb this phase transition. The adsorption of the copolymer unimers onto laponite in large amounts describes these findings. It is shown that the preferred adsorption of the copolymer chains results in a sufficient increase in free volume for the remaining micelles to yield the observed enhancement of the structural disorder.
小角中子散射和热流变技术被用于详细研究在高聚合物浓度或温度下，胶束溶液由于胶束的拥挤而发生从流体到晶体的相转变。加入皂土被发现会干扰这种相转变。大量的共聚物单体吸附到皂土上可以解释这些发现。结果表明，共聚物链的优先吸附导致自由体积的足够增加，从而使剩余的胶束产生观察到的结构无序增强。
