Chemistry Commons^™

Surface And Interfacial Design And Control Of High Performing Thermoplastics: Polysulfones And Beyond, Katrina Marie Knauer

Dissertations

The study of a class of materials almost always begins with the development of an understanding of properties in the bulk state. However, it is the study of surface critical phenomena that has led to a number of new important insights into polymer behavior. A systematic understanding of physical properties in the immediate vicinity of surface and interfacial layers, which cannot be deduced by simple extrapolation of bulk properties, is of significant importance for advancements in polymer applications where the interface drives performance, such as in membranes, coatings, drug-delivery systems, medical devices, and composites.

First, the surface and interfacial modification …

Studies Of Organic Compounds Spreading Over High Energy Surfaces, Lingbo Lu

Theses and Dissertations--Chemistry

Spreading plays an important role in coating, lubrication, printing and etc. During the spreading process, a liquid thin film forms prior to the expansion of a liquid drop. This thin film is called a precursor film. It not only changes the spreading mechanism, but impacts the wettability of a liquid. Early studies on the precursor films showed the films were stacked in a terraced structure, and the radius of each layer of the films was proportional to the square root of time. Optical techniques such as ellipsometry, X-ray diffraction and X-ray reflectivity solved the conformations of liquid molecules at the …

Scanning Probe Microscopy Studies Of The Properties Of Conducting Polymers, Kevin D. O'Neil

Electronic Thesis and Dissertation Repository

Electronically conducting polymers (ECPs) have been growing in interest as important materials for a variety of different applications such as charge storage devices and photovoltaics. However, in all of these applications, the performance of conducting polymers are strongly dependent upon their local properties such as morphology, local conductivity and carrier mobility, local chemical composition, etc. All polymer materials feature a distribution of these parameters and therefore, they are considered heterogeneous. In this work, we use atomic force microscopy (AFM) and its related techniques such as current-sensing AFM (CS-AFM), Kelvin probe force microscopy (KFM) and phase imaging (PI-AFM) to directly investigate …