Research Initiation Award: Molecular-Level Engineering of Polymer Interfaces in Colloidal Suspensions

本研究的目的是探索聚合物接枝胶体颗粒在水介质中的微观结构细节和宏观后果。利用生化连接剂的新型接枝技术将用于将聚环氧乙烷或其他聚合物接枝到功能化聚苯乙烯或二氧化硅颗粒上。功效分析技术，包括紫外吸收，核磁共振光谱，静态和动态光散射，和介电光谱。流变学测量，包括毛细管粘度测量、稳定剪切和恒定应力粘度测量、振荡和应力松弛，可以对聚合物介导的颗粒间力和悬浮液微观结构产生深入的了解。介电光谱技术将扩展到含有接枝聚合物的浓缩悬浮液。这些测量将与聚合物层结构、颗粒间力和悬浮流变学的扩展理论模型相结合，以使观察到的平衡特性和动态行为合理化。

The goal of this research is to explore the microstructural details and macroscopic consequences of polymer grafted colloidal particles in aqueous media. Novel grafting techniques utilizing biochemical linking agents will be used to graft poly(ethylene oxide) or other polymers onto functionalized polystyrene or silica particles. The efficacy of the analytical techniques, including UV absorbance, NMR spectroscopy, static and dynamic light scattering, and dielectric spectroscopy. Rheological measurements, including capillary viscometry, steady shear and constant stress viscometry, oscillation, and stress relaxation, yield insights regarding polymer-mediated interparticle forces and the suspension microstructure. The dielectric spectroscopy technique will be extended to concentrated suspensions containing grafted polymer. These measurements will be combined with extended theoretical models of polymer layer structure, interparticle forces, and suspension rheology in order to rationalize the observed equilibrium properties and dynamic behavior.