Hoffmann Martin, Lu Yan, Schrinner Marc, Ballauff Matthias, Harnau Ludger
Physikalische Chemie I, University of Bayreuth, 95440 Bayreuth, Germany.
J Phys Chem B. 2008 Nov 27;112(47):14843-50. doi: 10.1021/jp806765y.
We present the synthesis and comprehensive characterization of dumbbell-shaped polyelectrolyte brushes (DPB). The core of these particles consists of poly(methyl methacrylate) (PMMA) and poly(styrene) onto which a dense brush shell of poly(styrene sulfonate) is grafted. The morphology of DPB particles is studied in solution by cryogenic-transmission electron microscopy. We demonstrate that well-defined DPB are generated that react to external stimuli such as surfactant and salt concentration. The rotational diffusion and collective relaxations of the DPB particles were monitored by depolarized dynamic light scattering (DDLS). Here we found a new relaxation mode in the DDLS-signal that can be ascribed to collective fluctuations of the polyelectrolyte layer affixed to the surface of the dumbbells.
我们展示了哑铃状聚电解质刷（DPB）的合成及全面表征。这些粒子的核心由聚甲基丙烯酸甲酯（PMMA）和聚苯乙烯组成，在其上接枝了一层致密的聚苯乙烯磺酸盐刷状壳层。通过低温透射电子显微镜在溶液中研究了DPB粒子的形态。我们证明生成了定义明确的DPB，其对诸如表面活性剂和盐浓度等外部刺激有反应。通过去偏振动态光散射（DDLS）监测了DPB粒子的旋转扩散和集体弛豫。在此我们在DDLS信号中发现了一种新的弛豫模式，可归因于附着在哑铃表面的聚电解质层的集体涨落。
