2015 BFY II Abstract Detail Page
Previous Page |
New Search |
||A Differential Thermal Analysis Apparatus for Exploring the Glass Transition
||Glass is among the most common materials in our everyday lives. And yet the science behind this interesting, complex and ubiquitous material is seldom considered in the undergraduate science curriculum. The glass transition (Tg) is both a fundamental and defining concept in understanding the glassy state. To facilitate the experimental exploration of this important topic we have developed a simple home-built apparatus for measuring the glass transition (Tg) and the associated relaxation phenomena. While DSC (differential scanning calorimetry) is the most common technique for measuring Tg, such instruments are expensive and generally unavailable outside of the specialized materials research laboratory. However, differential thermal analysis (DTA) is somewhat simpler to implement and provides essentially the same information. We describe a simple DTA apparatus requiring only basic mechanical and electronic construction skills. Our DTA consists of measuring the temperature difference between test tubes with sample and reference materials, while heated in an aluminum enclosure. Our simple DTA provides excellent resolution of the Tg for low temperature glasses, such as sugar glasses. We also demonstrate the strong effect of thermal history, including the effect of quenching and aging. This apparatus provides an interesting and intuitive path to the student's exploration and understanding of the glassy state and can also provide a resource for deeper open-ended and independent study of relaxation phenomena.
William R. Heffner
7 Asa Drive
Download the Contributed Poster