Characterization of the Dynamic Behavior of Particle Contact Angle at an Oil/Water Interface

CBET-1604398PI：Snoeyink，CraigIg不相容的液滴被小的胶体颗粒包裹，称为胶体。它们被用于各种技术应用，包括药物输送、组织工程和食品保鲜。空气中的水胶体可用于气体传感和作为滚珠轴承。该项目的目标是开发一种新的实验技术，以确定粒子表面和界面之间的接触角如何影响界面的动力学和胶体的整体行为。这些结果将有助于从业者设计更好和更坚固的胶体，用于生物医学、传感和消费产品。该项目将为学生，特别是那些来自代表性不足群体的学生提供参与研究的机会，研究人员将为五年级到十一年级的夏令营开发一门软物质课程。三维粒子定位贝塞尔光束显微镜将被内置到界面流变仪中，以实时监控胶体粒子在界面变形(包括稳定和振荡剪切)高度受控的界面上的三维位置。从显微镜获得的图像将被分析，以确定20纳米分辨率的非球形粒子的位置和方向。将确定颗粒形状、界面微结构和界面流动对接触角分布和颗粒动力学的影响。这种方法是对当前接触角测量技术的重大改进，因为它将提供密实堆积颗粒在良好控制的界面变形下的位置和方向的实时数据。

CBET - 1604398PI: Snoeyink, CraigImmiscible liquid drops that are coated with small colloidal particles are known as colloidosomes. They are used in a variety of technological applications, including drug delivery, tissue engineering, and food preservation. Water colloidosomes in air are used in gas sensing and as ball bearings. The goal of this project is to develop a new experimental technique to determine how the contact angles between the surfaces of the particles and the interface influence the dynamics of the interface and the overall behavior of the colloidosomes. The results will be useful to practitioners to design better and more robust colloidsomes for use in biomedical, sensing, and consumer products. The project will provide opportunities for students, especially those from underrepresented groups, to participate in the research, and the researchers will develop a class in soft matter for a summer camp for grade five through eleven girls.Three-dimensional particle locating Bessel Beam microscopy will be built into an interfacial rheometer to allow real-time monitoring of the three-dimensional position of colloidal particles at an interface under highly controlled interfacial deformations including steady and oscillatory shear. Images obtained from the microscope will be analyzed to determine the position and orientation of nonspherical particles with twenty nanometer resolution. The effects of particle shape, interfacial microstructure, and interfacial flow on the contact angle distribution and particle dynamics will be determined. This method represents a significant improvement over current contact angle measurement techniques, because it will provide real-time data on the locations and orientations of densely packed particles under well-controlled interface deformations.