The kinetic study for asymmetric membrane formation via phase-inversion process
The kinetic study for asymmetric membrane formation via phase-inversion process
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DOI：
10.1002/(sici)1097-4628(19961024)62:4
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发表时间：
1996-10
影响因子：
3
通讯作者：
H. J. Kim;R. Tyagi;A. Fouda;K. Jonasson
中科院分区：
文献类型：
--
作者：
H. J. Kim;R. Tyagi;A. Fouda;K. Jonasson
通过相转化成膜的动力学进行了研究，强调在相分离过程中溶剂从聚合物溶液中扩散的速率。溶剂的扩散行为可以被认为是Fickian的。膜的形态被证明是强烈依赖于溶剂扩散的速率，这表明在相分离过程中的溶剂和非溶剂的传质速率是至关重要的，用于确定以下系统的最终膜结构：聚砜（聚合物），二甲基乙酰胺（溶剂），和乙醇（凝胶介质）。具体参考文献对大孔洞的形成机理进行了探讨。发现大空隙的形成与时间的平方根成正比，表明它受扩散过程的支配。此外，在大孔内观察到由浓缩聚合物相的成核和生长形成的凝结聚合物的胶乳颗粒。这样的结果意味着大空隙通过扩散流生长，该扩散流由在双节点分解期间聚合物贫相的生长引起。John Wiley & Sons，Inc.
The kinetics of membrane formation by phase inversion was studied emphasizing the rate of solvent diffusion from a polymer solution during the phase separation. Diffusional behavior of the solvent can be considered Fickian. Membrane morphologies were shown to be strongly dependent on the rate of solvent diffusion, indicating that mass-transfer rates of solvent and nonsolvent during phase separation are crucial for determining the final membrane structure for the following system: polysulfone (polymer), dimethyl acetamide (solvent), and ethanol (gelation medium). Specific reference to the mechanism of macrovoid formation was explored. Macrovoid formation was found to be proportional to the square root of time, suggesting that it is governed by a diffusion process. In addition, latex particles of coagulated polymer formed by the nucleation and growth of a concentrated polymer phase was observed inside the macrovoids. Such a result implies that the macrovoids grow by a diffusive flow which results from the growth of the polymer lean phase during binodal decomposition. © 1996 John Wiley & Sons, Inc.