The combination of Thermogravimetric Analysis with Infrared Spectroscopy (TG-IR) is the most common type of evolved gas analysis. Thermogravimetric Analysis (TGA) accurately measures the percentage weight loss of a sample as a function of temperature, but does not provide any information regarding the chemical composition of the evolved gases. Additionally, IR alone is not always sufficient for detecting the presence of components at low concentrations. This application note describes the development of a spectral library of TG-IR weight losses for polymers as well as the use of library-searching techniques for the identification of polymers and evolved gases from simple and more complex polymer formulations.