A 3D phase-field model for simulating the crystal growth of semi-crystalline polymers

Abstract

In this study a 3D phase-field model, which is a generalization of the 2D phase-field model we ever presented, has been established for investigating the crystal growth of semi-crystalline polymers. By coupling a non-conserved crystal order parameter with a temperature field which is generated by latent heat of crystallization, our developed model can obtain its model parameters from real material parameters. Unlike the model of metals and small molecular compounds, this model has considered the partial crystallization property of semi-crystalline polymers. Moreover, due to the long-chain molecular structure, polymer crystallizations usually exhibit complex anisotropy and have polymorphous nature. In order to account for the various anisotropy of interfacial energy in 3D, three anisotropic functions for describing the anisotropic interfacial growth patterns are deduced phenomenologically which are based on a number of existing experimental facts. Simulation results have preliminarily demonstrated the good performance of our phase-field model in reproducing the complex and diverse morphology of semi-crystalline polymers in 3D. Several kinds of crystal patterns, which have been observed in experiments, can be reproduced.