(731c) The Effects of Additives on PES Membrane Formation Vis Nips from Dissipative Particle Dynamics Simulations

Polymeric membranes produced by Non-solvent Induced Phase Separation (NIPS) have been extensively used across a wide array of microfiltration and ultrafiltration processes. However, despite their broad applications, current fabrication processes are largely empirical, determined by trial and error. Better insights into the factors affecting membrane morphology would be of great use. To that end, Dissipative Particle Dynamics (DPD), a mesoscale simulation tool, was used to simulate membrane formation process involving polyethersulfone (PES) in methyl-2-pyrrolidinone (NMP) with H₂O as a nonsolvent. The DPD simulations were performed for a total of several million beads and over several microseconds. The interactions between these beads are determined according to Flory-Huggins thermodynamic theory and continuum transport equation. In addition, the effects of additive polyethylene glycol (PEG) and its concentration on the thermodynamics and kinetics of PES membrane formation were investigated. Membrane morphology was found to depend strongly on the amount of additive included.