Predicting glass transition temperatures for structurally diverse polymers
摘要
This work proposes an accurate quantitative structure–property relationship (QSPR) model for glass transition temperatures (Tgs) of 315 polymers with diverse structures. Support vector regression (SVR), combined with a genetic algorithm, was used to develop the SVR model that achieved a determination coefficient (R2) of 0.937 and a root-mean-square (rms) error of 25.047 K for 79 Tgs of polymers in the test set. The investigation shows that increasing the percentage of C atoms, molecular polarity, complementary information content index, spectral mean absolute deviation and eigenvalue in augmented adjacency matrix by introducing benzene, naphthalene, anthracene, pyridine, quinoline, imide, and/or C‒N atom pairs with a topological distance of 9, can result in high chain rigidity and high Tgs. Conversely, increasing the free volume and flexible segments by introducing groups such as ‒Si‒O‒, ‒Si‒C‒, and ‒Si‒N‒ in the backbone chain, N and O atom pairs, S and X (heteroatoms) atom pairs with a topological distance of 1, F‒X with a topological distance of 2 and CH2RX groups can bring down Tgs.
Graphical Abstract