Kang Jia-Jhen, Sachse Clemens, Ko Chia-Hsin, Schroer Martin A, Vela Stefano Da, Molodenskiy Dmitry, Kohlbrecher Joachim, Bushuev Nikita V, Gumerov Rustam A, Potemkin Igor I, Jordan Rainer, Papadakis Christine M
Fachgebiet Physik weicher Materie, Physik-Department, Technische Universität München, James-Franck-Straße 1, 85748 Garching, Germany.
Professur für Makromolekulare Chemie, Fakultät Chemie und Lebensmittelchemie, Technische Universität Dresden, Mommsenstraße 4, 01069 Dresden, Germany.
Langmuir. 2022 May 3;38(17):5226-5236. doi: 10.1021/acs.langmuir.1c02589. Epub 2022 Feb 15.
The structures of a molecular brush in a good solvent are investigated using synchrotron small-angle X-ray scattering in a wide range of concentrations. The brush under study, PPOx--PPrOx, features a relatively long poly(2-isopropenyl-2-oxazoline) (PPOx) backbone and short poly(2--propyl-2-oxazoline) (PPrOx) side chains. As a solvent, ethanol is used. By model fitting, the overall size and the persistence length as well as the interaction length and interaction strength are determined. At this, the interplay between form and structure factor is taken into account. The conformation of the molecular brush is traced upon increasing the solution concentration, and a rigid-to-flexible transition is found near the overlap concentration. Finally, the results of computer simulations of the molecular brush solutions confirm the experimental results.
使用同步加速器小角X射线散射在广泛的浓度范围内研究了良溶剂中分子刷的结构。所研究的分子刷PPOx-PPrOx具有相对较长的聚（2-异丙烯基-2-恶唑啉）（PPOx）主链和短的聚（2-丙基-2-恶唑啉）（PPrOx）侧链。作为溶剂，使用乙醇。通过模型拟合，确定了整体尺寸、持久长度以及相互作用长度和相互作用强度。在此过程中，考虑了形状因子和结构因子之间的相互作用。随着溶液浓度的增加追踪分子刷的构象，发现在重叠浓度附近存在从刚性到柔性的转变。最后，分子刷溶液的计算机模拟结果证实了实验结果。
