Sanchez-Fernandez Adrian, Larsson Johan, Leung Anna E, Holmqvist Peter, Czakkel Orsolya, Nylander Tommy, Ulvenlund Stefan, Wahlgren Marie
Food Technology, Engineering and Nutrition, Lund University, Box 124, 221 00 Lund, Sweden.
Biofilms Research Center for Biointerfaces and Department of Biomedical Science, Faculty of Health and Society, Malmö University, Per Albin Hanssons Väg 35, 21432 Malmö, Sweden.
Langmuir. 2022 Aug 23;38(33):10075-10080. doi: 10.1021/acs.langmuir.2c00230. Epub 2022 Aug 1.
The molecular architecture of sugar-based surfactants strongly affects their self-assembled structure, i.e., the type of micelles they form, which in turn controls both the dynamics and rheological properties of the system. Here, we report the segmental and mesoscopic structure and dynamics of a series of C16 maltosides with differences in the anomeric configuration and degree of tail unsaturation. Neutron spin-echo measurements showed that the segmental dynamics can be modeled as a one-dimensional array of segments where the dynamics increase with inefficient monomer packing. The network dynamics as characterized by dynamic light scattering show different relaxation modes that can be associated with the micelle structure. Hindered dynamics are observed for arrested networks of worm-like micelles, connected to their shear-thinning rheology, while nonentangled diffusing rods relate to Newtonian rheological behavior. While the design of novel surfactants with controlled properties poses a challenge for synthetic chemistry, we demonstrate how simple variations in the monomer structure can significantly influence the behavior of surfactants.
糖基表面活性剂的分子结构强烈影响其自组装结构，即它们形成的胶束类型，这反过来又控制了体系的动力学和流变性质。在此，我们报道了一系列在异头构型和尾部不饱和度上存在差异的C16麦芽糖苷的链段和介观结构及动力学。中子自旋回波测量表明，链段动力学可以建模为一维链段阵列，其中动力学随着单体堆积效率低下而增加。以动态光散射表征的网络动力学显示出不同的弛豫模式，这些模式可以与胶束结构相关联。对于蠕虫状胶束的停滞网络观察到受阻动力学，这与其剪切变稀流变学相关，而无缠结的扩散棒则与牛顿流变行为相关。虽然设计具有可控性质的新型表面活性剂对合成化学构成挑战，但我们展示了单体结构的简单变化如何能显著影响表面活性剂的行为。
