Thermal analysis is defined as a group of methods based on the determination of changes in chemical or physical properties of material as a function of temperature in a controlled atmosphere. The principal techniques of thermal analysis are differential scanning calorimetry (DSC) and dynamic thermogravimetry (TGA).
DCS and TGA methods are used in all phases of research, quality control and production operations. Therefore, the list of tested materials is very broad. It includes polymers and gels, ceramics, minerals, archeological artifacts, metals and metal glasses, nanocatalysts, biomaterials like peptides, drugs, biological membranes, etc. (Table 1).
Table 1. Examples of materials tested by thermal analysis
DSC measures heat flow associated with transitions in materials as a function of time and temperature in the range of -100 to 725°C. Generally speaking, phase transitions (melting and boiling), dehydration, reduction and some decomposition reactions produce endothermic effects, whereas crystallization and oxidation produce exothermic effects. Specific measurements made by DSC include glass transitions, melting and boiling points, crystallization time and temperature, purity, percent crystallinity, degree and rate of cure, specific heat and heats of fusion and reactions, kinetics and mechanism of reactions, oxidative and thermal stability. It also provides quantitative and qualitative data on endothermic (heat absorption) and exothermic (heat evolution) processes of materials during physical transitions that are caused by phase changes and other heat-related changes.
The equipment of WARMC thermal analysis lab includes: Q2000 MDSC, Discovery Refrigerated Cooling System - RCS90, TGA-IR Q5000 IR system, Nicolet iS50 spectrometer.