Structures and gas separation properties of asymmetric polysulfone membranes made by dry, wet, and dry/wet phase inversion

Materials used for medical applications (e.g., the cellular scaffold) should have not only the specific chemical composition, but the surface layer properties as well. For this reason, a method which enables an increase in the number of pores, wettability of the surface, and improvement the conditions of nutrient transportation into the membrane is being studied. The plasma of a dielectric barrier discharge was applied for the surface modification of polylactide obtained by dry or wet phase inversion. The plasma-modified surface was analyzed by contact angle measurements with water and diiodomethane. The surface free energy (SFE) was calculated by the Owens–Wendt method. The highest SFE and its polar component (67.6 mJ/m2 and 39.5 mJ/m2, respectively) were received when the process was conducted in an Ar + CO2 gas mixture with a discharge power of 20 W. The purpose of this research was to increase the wettability and porosity of the membrane’s surface. It can be concluded that the dielectric barrier discharge can effectively change the surface of the polylactide membranes, and that the structure of the modified membranes was not damaged during modification. The process of modification was easier for the membranes made by dry phase inversion. These materials had higher SFE values after the modification.

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Development of defect-free asymmetric polysulfone membranes for gas separation using response surface methodology

Separation and Purification Technology ◽

10.1016/j.seppur.2004.02.011 ◽

2004 ◽

Vol 40 (2) ◽

pp. 191-207 ◽

Cited By ~ 61

Author(s):

A.F. Ismail ◽

P.Y. Lai

Keyword(s):

Response Surface Methodology ◽

Response Surface ◽

Gas Separation ◽

Polysulfone Membranes

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Study on Structure and Properties of Polysulfone Membranes Using Ionic Liquid [n-C16mim][BF4] as a New Structure-Controlled Additive

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.561.125 ◽

2013 ◽

Vol 561 ◽

pp. 125-129 ◽

Cited By ~ 1

Author(s):

Ying Ying Ding ◽

Ya Mei Zhao ◽

Chang Zheng Zheng ◽

Dong Huai Tu

Keyword(s):

Ionic Liquid ◽

Cross Sections ◽

Retention Rate ◽

Contact Angles ◽

Asymmetric Structure ◽

Polysulfone Membrane ◽

Force Microscopy ◽

Wet Phase Inversion ◽

Surface Morphologies ◽

Polysulfone Membranes

Introducing ionic liquid [n-C16mim][BF4] as a new structure-controlled additive, Polysulfone (PSf) membranes were prepared by the wet-phase-inversion using [n-C16mim][BF4] into the casting solution (PSf/NMP). The scanning electron microscope and the atomic force microscopy were utilized to visualize the cross-sections of the membranes to gain more better understanding the structure-controlled ability of [n-C16mim][BF4] and surface morphologies of the membrane. The results indicate that the structures of the membranes were typical bilayer asymmetric finger-pores structure. [n-C16mim][BF4] has stronger ability of the pore-forming. Especially, at the 4:76 ratio of [n-C16mim][BF4]/NMP in the polymer solution ,the membrane has the asymmetric structure and good separation properties of the solution flux. The PSf membrane has the 0.45~0.65μm dimpling close to surface layer, and the retention rate and solution flux of the prepared membrane are 95.2% and 137.5 L•h-1•m-2. Meanwhile, [n-C16mim][BF4] partially retained in the prepared Polysulfone membrane reduced the contact angles of Polysulfone membranes, improving the hydrophilic properties of the membranes.

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