Poly(vinylidene fluoride)/polyethersulfone blend membranes: Effects of solvent sort, polyethersulfone and polyvinylpyrrolidone concentration on their properties and morphology

Wu, Lishun; Sun, Jiatong; Wang, Qingrui

doi:10.1016/j.memsci.2006.08.033

Cited by 123 publications

(61 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Such a thing delays the precipitation of casting-solution and enhances the homogenous structures forming. These results are in agreement with those of Wu et al [23] who suggest that weak interactions between polyvinylidene fluoride and poly (ethersulfone) chains tend to create a large distance between the polymers chains which induces the formation of macrovoid-structures.…”

Section: Effect Of the Blend Compositionsupporting

confidence: 93%

Study of Polysulfone and Polyacrylic Acid (PSF/PAA) Membranes Morphology by Kinetic Method and Scanning Electronic Microscopy

Mbareck¹

2015

J Membra Sci Technol

View full text Add to dashboard Cite

Experiment Polymer propertiesPolysulfone (PSf) and poly (acrylic acid) (PAA) were supplied by Aldrich and dimethyl formamide (DMF) by Prolabo. All polymers and chemical products were used as supplied, without any further purification. Molecular weights of PAA and PSf were 450 000 and 26 000 g/mol, respectively. Membrane preparationPolysulfone (PSf) and Poly (acrylic acid) (PAA) were dissolved, separately, in dimethyl formamide (DMF) in a glass reactor equipped with a mechanical stirrer and thermostated at 90°C for over 3 hours. The PSf concentration was 17 (or 19) wt. % and that of PAA was 5 wt. %. Afterwards, both solutions were mixed together in known proportions, stirred for 30 min and de-bubbled. Such de-bubbled casting-solution was casted on a glass plate with a lab-made Gardner knife, dried in freeair for a known time (generally 20 seconds) and finally immersed in a coagulation-bath containing a sufficient volume of MilliQ water (18.2 MΩcm) at 18°C. Membranes were thoroughly washed with water, and stored in a dilute sodium azide solution till their use. Kinetic measurementFive polymer-solutions with the same mass (2 g) and different composition (PSf/PAA 100/0, 96/04, 92/08, 89/11 and 83/17) were poured on a glass plate to get exactly a same surface area. Afterwards, AbstractThis work focuses on the study of the morphology forming of Polysulfone (PSf) and polyacrylic acid (PAA) membranes which are prepared by mixing both of the polymers in DMF and the obtained blend is precipitated in water (non-solvent). The precipitation kinetic and the effects of polysulfone concentration, drying-time in free-air and proportions of both polymers are investigated.Based on the SEM technique, the kinetic and viscosity measurements, and the visual observations, this study brings to the fore the different steps of the morphology forming of PSf/PAA membranes: formation of finger-like structures, sponge-like-structures, inner pores, superficial pores and the craters. Appearance of these structures is governed by the exchange process, between casting polymer-solution and the precipitation-bath (coagulation), which is controlled by operating conditions. This work constitutes a great tool in understanding the mechanisms of the morphology forming of PSf/PAA membranes and to improve their performances: preparation of tailored membrane.

show abstract

Section: Effect Of the Blend Compositionsupporting

confidence: 93%

Study of Polysulfone and Polyacrylic Acid (PSF/PAA) Membranes Morphology by Kinetic Method and Scanning Electronic Microscopy

Mbareck¹

2015

J Membra Sci Technol

View full text Add to dashboard Cite

show abstract

“…Hence, PVDF has been a subject of active research in polymer science and has received increasing attention for various membrane separations [16]. Although an extensive series of studies have been carried out to fabricate PVDF membranes in order to improve their properties, most of them are focused on preparation of flat sheet membranes [17][18][19][20] and hydrophilic hollow fiber membranes [21][22][23][24][25], less research has been conducted on the fabrication and characterization of hydrophobic porous PVDF hollow fiber membranes mainly for the MD process [1].…”

Section: Introductionmentioning

confidence: 99%

Fabrication and characterization of hydrophobic PVDF hollow fiber membranes for desalination through direct contact membrane distillation

Hou

Wang

et al. 2009

Separation and Purification Technology

132

View full text Add to dashboard Cite

a b s t r a c tThe mixture of inorganic salt LiCl and soluble polymer polyethylene glycol (PEG) 1500 as non-solvent additive was introduced to fabricate hydrophobic hollow fiber membrane of polyvinylidene fluoride (PVDF) by phase inversion process, using N,N-dimethylacetamide (DMAc) as solvent and tap water as the coagulation medium. Compared with other three membranes from PVDF/DMAc, PVDF/DMAc/LiCl and PVDF/DMAc/PEG 1500 dope solution, it can be observed obviously by scanning electron microscope (SEM) that the membrane spun from PVDF/DMAc/LiCl/PEG 1500 dope had longer finger-like cavities, ultra-thin skins, narrow pore size distribution and porous network sponge-like structure owing to the synergistic effect of LiCl and PEG 1500. Besides, the membrane also exhibited high porosity and good hydrophobicity. During the desalination process of 3.5 wt% sodium chloride solution through direct contact membrane distillation (DCMD), the permeate flux achieved 40.5 kg/m 2 h and the rejection of NaCl maintained 99.99% with the feed solution at 81.8• C and the cold distillate water at 20.0 • C, this performance is comparable or even higher than most of the previous reports. Furthermore, a 200 h continuously desalination experiment showed that the membrane had stable permeate flux and solute rejection, indicating that the as-spun PVDF hollow fiber membrane may be of great potential to be utilized in the DCMD process.

show abstract

“…Although an extensive series of studies has been carried out to fabricate various PVDF membranes in order to improve membrane properties, most of them are focused on preparation of flat sheet membranes (Lin et al 2002;Fontananova et al 2006;Buonomenna et al 2007;Seol et al 2007) and hydrophilic composite hollow fiber membranes (Singh et al 2005;Feng et al 2006;Wu et al 2006;Zhao et al 2008;Zhou & Xi 2008). On the contrary, as far as we know, less research has been conducted on the fabrication and characterization of hydrophobic porous PVDF hollow fiber membranes mainly for the MD process.…”

Section: Introductionmentioning

confidence: 99%

Preparation of hydrophobic PVDF hollow fiber membranes for desalination through membrane distillation

Hou

Wang

et al. 2009

Water Science and Technology

View full text Add to dashboard Cite

Fabrication of polyvinylidene fluoride (PVDF) hydrophobic asymmetric hollow fiber membranes was studied by introducing inorganic salt LiCl and water soluble polymer polyethylene glycol (PEG) 1500, using N,N-dimethylacetamide (DMAc) as solvent and tap water as the coagulation medium. The membranes properties also were tested and characterized. It is found that the nonsolvent additive can increase membranes porosity, ether LiCl or PEG 1500. Because of the addition of PEG 1500, the PVDF membranes obtained a rough topography on the membrane surface and the contact angle of the PVDF membranes increased to 113.508 compared to 89.828 of the PVDF membranes spun without an additive. During direct contact membrane distillation (DCMD) of 0.6 M sodium chloride solution, the PVDF membranes spun with PEG 1500 as a non-solvent additive achieved higher water permeation flux compared to the membranes spun from PVDF/DMAc and PVDF/DMAC/LiCl dopes, but the latter two membranes exhibited higher salt rejection rate.

show abstract

Poly(vinylidene fluoride)/polyethersulfone blend membranes: Effects of solvent sort, polyethersulfone and polyvinylpyrrolidone concentration on their properties and morphology

Cited by 123 publications

References 16 publications

Study of Polysulfone and Polyacrylic Acid (PSF/PAA) Membranes Morphology by Kinetic Method and Scanning Electronic Microscopy

Study of Polysulfone and Polyacrylic Acid (PSF/PAA) Membranes Morphology by Kinetic Method and Scanning Electronic Microscopy

Fabrication and characterization of hydrophobic PVDF hollow fiber membranes for desalination through direct contact membrane distillation

Preparation of hydrophobic PVDF hollow fiber membranes for desalination through membrane distillation

Contact Info

Product

Resources

About