A new dissipative particle dynamics (DPD) simulation methodology adopting a mass transfer algorithm was established to investigate the membrane formation process via nonsolvent induced phase separation (NIPS). The effect of the interphase mass transfer between the casting solution and the nonsolvent bath on the membrane formation process and the membrane morphology was elaborately analyzed. Factors including the solvent–nonsolvent interaction, the polymer concentration and the nonsolvent temperature were considered. The results showed that as the solvent-nonsolvent interaction got better, the mass transfer was intensified which contributed to an intense phase separation. Thereby asymmetric membrane morphology with a thick dense surface layer and a porous sub-layer would be formed. With the nonsolvent temperature raising, the relatively symmetric morphology with small pores was obtained due to the declined polymer aggregation rate and the increased phase separation rate caused by the accelerated mass transfer. As the polymer concentration increased, the flexibility of the system reduced. Thereby the phase separation slowed down, resulting in highly asymmetric morphology with a thicker and denser surface layer and a more porous sub-layer. The analysis of the phase separation in this study benefits to a better understanding on the mechanism of the membrane structure formation via NIPS.

建立了一种采用传质算法的耗散粒子动力学（DPD）模拟新方法，以研究通过非溶剂诱导相分离（NIPS）的膜形成过程。详细分析了流延溶液和非溶剂浴之间的相间传质对膜形成过程和膜形态的影响。考虑了包括溶剂-非溶剂相互作用，聚合物浓度和非溶剂温度在内的因素。结果表明，随着溶剂-非溶剂相互作用的改善，传质加剧，促进了强烈的相分离。由此将形成具有厚的致密表面层和多孔子层的不对称膜形态。随着非溶剂温度的升高，由于聚合物聚集速率的下降和加速传质引起的相分离率的提高，获得了具有小孔的相对对称的形貌。随着聚合物浓度的增加，系统的柔韧性降低。因此，相分离变慢，导致高度不对称的形态，具有更厚和更密的表面层以及更多孔的子层。本研究中的相分离分析有助于更好地了解通过NIPS形成膜结构的机理。导致高度不对称的形貌，具有更厚，更密的表面层和更多孔的子层。本研究中的相分离分析有助于更好地了解通过NIPS形成膜结构的机理。导致高度不对称的形貌，具有更厚，更密的表面层和更多孔的子层。本研究中的相分离分析有助于更好地了解通过NIPS形成膜结构的机理。