Machine Learning Models Predicting Solubility and Polymerizability of Polyimides Considering Multiple Monomers for CO2 Separation Membranes.

Membrane technologies for the separation of gases, such as CO2/CH4 mixtures, have attracted attention because of their high energy efficiency. Polyimides are considered promising membrane materials for CO2 separation, and there is a growing demand for materials with even higher performance. In the screening of candidate materials, it is essential to consider not only separation performance but also solubility and polymerizability during the synthesis process. Low solubility or polymerizability can inhibit membrane fabrication and the evaluation of separation performance, potentially leading to wasted resources and effort. In this study, we developed machine learning models to predict the solubility and polymerizability of polyimides. Mixture features derived from molecular descriptors of multiple monomers and mixing ratios were used as inputs for the classification models. The models were then applied to novel candidates, and their effectiveness was validated experimentally.