Speaker: Randy Youngman, Corning
Title: Nuclear Magnetic Resonance Spectroscopy and Glass Science
Abstract:
Corning Incorporated has been in existence for over 160 years, and throughout this time has specialized in the invention and commercialization of advantaged glass products. Some of the key glass inventions from our research laboratories have included Pyrex® borosilicate glass for consumer and scientific use, optical fiber for telecommunications, CorningWare® and other glass-ceramic materials, HPFS® and ULE® glasses for mirror blanks and applications requiring extremely tight thermal expansion tolerances, and more recently and perhaps more famously, thin glass for LCD substrates and strong cover glass for consumer electronics (Corning® Gorilla® Glass). As part of this lengthy history of innovation, especially in glass science, we continue to conduct significant exploratory and fundamental research.
In our efforts to develop and commercialize new glass compositions and products, characterization of their properties and underlying network structures is critical. Advances in structure-property understanding have necessitated similar advances in the measurement of short- and intermediate-range structure. One of the key structural characterization tools in glass research is NMR spectroscopy. This presentation will focus on the importance of NMR techniques in glass research, with emphasis on two different research topics. The first involves the study of structure and properties in modifier-free glasses. These glasses are unique in their relative simplicity and provide an opportunity to learn about the direct linkages between structure and properties. In addition, these glasses highlight the role of phosphorus, which is an important additive in many glass-forming systems.
The second topic will focus on recent research into the impact of compression on both the structure and properties of multi-component oxide glasses. Application of pressure while holding the glasses near their glass transition temperatures, results in permanent densification. This treatment yields glasses with different mechanical properties (e.g. hardness) and a significant change in the network structure. NMR studies of these compressed glasses reveals the impact of pressure on cation coordination and provides a means by which to study compression conditions (time, temperature, pressure) and post-compression thermal relaxation. The latter leads to a recovery of most glass properties, but not necessarily the ambient pressure glass structure.