A Molecular Dynamics Simulation Study on the Miscibility of Polyglycolide with Polyacrylonitrile

Atomistic molecular dynamics and mesoscopic dynamics simulations are used to study the miscibility of polyglycolide (PGA) blended with polyacrylonitrile (PAN). Seven PGA/PAN blends (with weight ratios of 90/10, 80/20, 70/30, 60/40 and 50/50), as well as pure PGA and PAN, are examined. The Flory Huggins parameters, phase diagrams, radial distribution function, free energy, and order parameters are computed for different blends using atomistic simulations to predict blend miscibility. The simulation results show that the PGA/PAN blends have good miscibility for all the weight ratios investigated. This is further supported by the morphologies of PGA/PAN blends. The phase separation kinetics of PGA/PAN blends is then examined using density profiles calculated from the Mesodyn approach to examine the mesoscopic morphology of the blends. The results strengthen the conclusion that the blends can be miscible in the above-mentioned range of ratios, in agreement with those found in the literature.