The Use of Thermogravimetric Analysis as a Rapid Screening Test for Large Numbers of Experimental Insulations

A method has been devised for rapidly determining the thermal stability of polymers. It is based upon a previously described thermogravimetric method for predicting the thermal ratings of wire enamels. By using only one thermogram per sample and at a standard heating rate, determining the activation energy, and assuming a 50-percent weight-loss failure criterion, the approximate thermal rating is fixed and read off a diagram. During chemical development work, when a series of structural modifications to the polymer is carried out, the progress can be mapped on the diagram and the experimental program thereby accelerated.