Multiscale modeling of polymer materials using a statistics-based micromechanics approach

A large number of possible polymer chain conformations exist for a given volume of an amorphous polymer. The prediction of elastic properties of a polymer must therefore consider more than a single combination of chain conformations. A multiscale modeling approach is proposed to predict the bulk elastic properties of polymer materials using a series of molecular models of individual polymer microstates and a statistics-based micromechanical modeling method. The method is applied to polyimide and polycarbonate systems. It is shown that individual microstates can yield a wide range of predicted elastic properties, whereas the consideration of multiple microstates yield predicted properties that agree more closely with experimentally determined values of Young’s modulus. Additionally, the upper and lower limits of possible elastic constants are also established based on the consideration of multiple microstates.