State Key Laboratory of Chemical Engineering, Engineering Research Center of Large Scale Reactor Engineering and Technology (Ministry of Education), and International Joint Research Center of Green Energy Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, P.R. China.
Technical University Darmstadt, Department of Physics, Soft Matter at Interfaces, Darmstadt 64287, Germany.
Langmuir. 2020 Mar 31;36(12):3104-3110. doi: 10.1021/acs.langmuir.9b03180. Epub 2020 Mar 20.
Interaction among concentrated spherical polyelectrolyte brushes (SPB) dispersions in water was systematically investigated by means of small-angle X-ray scattering (SAXS), wide-angle X-ray scattering (WAXS), and rheological methods. SPB consist of a core of polystyrene (PS) and a poly(acrylic acid) (PAA) brush shell. The "polyelectrolyte peak" appeared in SAXS spectra and was observed in WAXS curves for the first time. The size of the polyelectrolyte peak and the rheological properties of SPB were found to be strongly effected by SPB concentration, pH, and ionic strength. Combined with SAXS, WAXS, and rheological results, it is confirmed that the polyelectrolyte peak is originated from local ordered structures of polyelectrolyte chains bridged by counterions in the overlapping area among SPB driven by electrostatic interactions.
通过小角 X 射线散射（SAXS）、广角 X 射线散射（WAXS）和流变学方法，系统地研究了水中浓缩球形聚电解质刷（SPB）分散体之间的相互作用。SPB 由聚苯乙烯（PS）核和聚丙烯酸（PAA）刷壳组成。“聚电解质峰”首次出现在 SAXS 光谱中，并在 WAXS 曲线上观察到。发现聚电解质峰的大小和 SPB 的流变性能强烈受 SPB 浓度、pH 值和离子强度的影响。结合 SAXS、WAXS 和流变学结果，证实聚电解质峰是由静电相互作用驱动的 SPB 重叠区域中被反离子桥接的聚电解质链的局部有序结构引起的。
