Study on the Impact of Polymer Concentration and Coagulation Bath Temperature on the Porosity of Polyethylene Membranes Fabricated Via TIPS Method

Ali Akbari; Reza Yegani

doi:10.6000/1929-6037.2012.01.02.4

Authors

Ali Akbari Faculty of Chemical Engineering, Sahand University of Technology, Sahand New Town, Post Box 51335/1996, Tabriz, Iran
Reza Yegani Faculty of Chemical Engineering, Sahand University of Technology, Sahand New Town, Post Box 51335/1996, Tabriz, Iran

DOI:

https://doi.org/10.6000/1929-6037.2012.01.02.4

Keywords:

HDPE membrane, Experimental design, Analysis of variance (ANOVA), Leafy structure, Spherulitical structure

Abstract

Microporous high density polyethylene flat membranes were fabricated via thermally induced phase separation (TIPS) method. Effects of polymer concentration and coagulation bath temperature on the membrane morphology and porosity were investigated. To the best of our knowledge, there is no work about the order of magnitude and degree of importance of influential parameters and their interactions on the microstructure of fabricated membranes. The results showed that the porosity of membranes decreased as the polymer concentration increased. It was also shown that, due to the short contact time and rapid phase inversion between coagulation bath and membrane’s outer surfaces, bath temperature mainly affects on the outer surface porosity. The results obtained from analysis of variance (ANOVA) using 95% confidence interval on the membrane porosity revealed that the effect of polymer concentration is more important than coagulation bath temperature.

References

Sun H, Rhee KB, Kitano T, Mah SI. High-density polyethylene (HDPE) hollow fiber membrane via thermally induced phase separation. I. Phase separation behaviors of HDPE–liquid paraffin (LP) blends and its influence on the morphology of the membrane. J Appl Polym Sci 1999; 73: 2135-42. http://dx.doi.org/10.1002/(SICI)1097-4628(19990912)73:11<2135::AID-APP9>3.0.CO;2-X

Mulder M. Basic Principles of Membrane Technology, 2 ed., Kluwer Academic 1996.

Liu S, Zhou C, Yu W. Phase separation and structure control in ultra-high molecular weight polyethylene microporous membrane. J Membr Sci 2011; 379: 268-78. http://dx.doi.org/10.1016/j.memsci.2011.05.073

Rajabzadeh S, Maruyama T, Sotani T, Matsuyama H. Preparation of PVDF hollow fiber membrane from a ternary polymer/solvent/nonsolvent system via thermally induced phase separation (TIPS) method. Separat Purificat Technol 2008; 63: 415-23. http://dx.doi.org/10.1016/j.seppur.2008.05.027

Lloyd DR, Kinzer KE, Tseng HS. Microporous membrane formation via thermally induced phase separation. I. Solid-liquid phase separation. J Membr Sci 1990; 52: 239-61. http://dx.doi.org/10.1016/S0376-7388(00)85130-3

Lloyd DR, Kim SS, Kinzer KE. Microporous membrane formation via thermally-induced phase separation. II. Liquid--liquid phase separation. J Membr Sci 1991; 64: 1-11. http://dx.doi.org/10.1016/0376-7388(91)80073-F

Kim SS, Lloyd DR. Microporous membrane formation via thermally-induced phase separation. III. Effect of thermodynamic interactions on the structure of isotactic polypropylene membranes. J Membr Sci 1991; 64: 13-29. http://dx.doi.org/10.1016/0376-7388(91)80074-G

Lim GBA, Kim SS, Ye Q, Wang YF, Lloyd DR. Microporous membrane formation via thermally-induced phase separation. IV. Effect of isotactic polypropylene crystallization kinetics on membrane structure. J Membr Sci 1991; 64: 31-40. http://dx.doi.org/10.1016/0376-7388(91)80075-H

Kim SS, Lim GBA, Alwattari AA, Wang YF, Lloyd DR. Microporous membrane formation via thermally-induced phase separation. V. Effect of diluent mobility and crystallization on the structure of isotactic polypropylene membranes. J Membr Sci 1991; 64: 41-53. http://dx.doi.org/10.1016/0376-7388(91)80076-I

Alwattari AA, Lloyd DR. Microporous membrane formation via thermally-induced phase separation. VI. Effect of diluent morphology and relative crystallization kinetics on polypropylene membrane structure. J Membr Sci 1991; 64: 55-67. http://dx.doi.org/10.1016/0376-7388(91)80077-J

McGuire KS, Lloyd DR, Lim GBA. Microporous membrane formation via thermally-induced phase separation. VII. Effect of dilution, cooling rate, and nucleating agent addition on morphology. J Membr Sci 1993; 79: 27-34. http://dx.doi.org/10.1016/0376-7388(93)85015-O

Matsuyama H, Hayashi K, Maki T, Teramoto M, Kubota N. Effect of polymer density on polyethylene hollow fiber membrane formation via thermally induced phase separation. J Appl Polym Sci 2004; 93: 471-74. http://dx.doi.org/10.1002/app.20461

Matsuyama H, Okafuji H, Maki T, Teramoto M, Kubota N. Preparation of polyethylene hollow fiber membrane via thermally induced phase separation. J Membr Sci 2003; 223: 119-26. http://dx.doi.org/10.1016/S0376-7388(03)00314-4

Sun H, Rhee KB, Kitano T, Mah SI. HDPE hollow-fiber membrane via thermally induced phase separation. II. Factors affecting the water permeability of the membrane. J Appl Polym Sci 2000; 75: 1235-42. http://dx.doi.org/10.1002/(SICI)1097-4628(20000307)75:10<1235::AID-APP4>3.0.CO;2-D

Montgomery DC. Design and Analysis of Experiments, John Wiley & Sons Australia, Limited 1999.

Shokri E, Yegani R. Full-Factorial experimental design to determine the impacts of influential parameters on the porosity and mechanical strength of LLDEP microporous membrane fabricated via thermally induced phase separation method. J Membr Separat Technol 2012; 1(1): 43-51.

Li X, Wang Y, Lu X, Xiao C. Morphology changes of polyvinylidene fluoride membrane under different phase separation mechanisms. J Membr Sci 2008; 320: 477-82. http://dx.doi.org/10.1016/j.memsci.2008.04.033

Voigt-Martin IG, Fischer EW, Mandelkern L. Morphology of melt-crystallized linear polyethylene fractions and its dependence on molecular weight and crystallization temperature. J Polym Sci Polym Phys Ed 1980; 18: 2347-67. http://dx.doi.org/10.1002/pol.1980.180181204

Wenjun L, Youxin Y, Israel C. Formation and microstructure of polyethylene microporous membranes through thermally induced phase separation. Chin J Polym Sci 1995; 13: 7-19.