A general method for assessment of glass transition temperature of polymeric materials only from various structural factors in their repeating unit structure

Abstract

The glass transition temperature (Tg) of polymeric materials can be used to assess their stability because physical properties can be changed at this temperature. In contrast to previous general methods for predicting Tg of different polymers where they need computer codes, and expert users, the novel method can be used as a simple computer code because it requires only various structural factors in their repeating unit structure. The most extensive available reported data of Tg for 388 different organic polymers, such as polyacrylates, polystyrenes, polyvinyls, polycarbonates, polyxylylenes, polyimides, and polyquinolines, are used to derive and test the new model. Assessment of the high reliability of the novel method is done by considering diverse types of statistical factors and compared with the outputs of five models. The values of the coefficient of determination (r2)/Root Mean Square Error (RMSE) of the new model for 154, 52, and 38 data of training, test, and external sets are 0.846/0.049, 0.832/0.052, and 0.841/0.064, respectively, which are higher/lower (or close) than the five comparative models. For further 104 polymers where the computed outputs of comparative models were unavailable, the r2 value is relatively good, i.e., 0.851.