Polysulfone membrane treated with NH3-O2 plasma and its property

2017 ◽  
Vol 30 (9) ◽  
pp. 1139-1144 ◽  
Author(s):  
Xuanxuan Zhang ◽  
Shengjie Zhang ◽  
Yufei Wang ◽  
Yi Zheng ◽  
Yu Han ◽  
...  
Keyword(s):  
Contact Angle ◽  
Membrane Surface ◽  
Time Effect ◽  
Attenuated Total Reflection ◽  
Buffer Solution ◽  
Filtration Process ◽  
Polysulfone Membrane ◽  
X Ray ◽  
Membrane Contact ◽  
Peroxy Group

The character of ammonia-oxygen (NH3-O2) plasma-treated polysulfone (PSF) membrane was studied in this work. The time effect of the plasma-treated PSF membrane was checked with energy-dispersive X-ray (EDX) detector, attenuated total reflection Fourier transform infrared (ATR-FTIR), membrane contact angle, and filtration property. EDX detector and ATR-FTIR spectra have shown that the surface oxygen content of the modified membrane increased in the form of peroxy, hydroxyl, and aromatic carboxide groups. However, nitrogen was not observed in the NH3-O2 plasma-treated membrane surface. The peroxy group disappeared and hydroxyl and aromatic carboxide groups were reduced 3 months later. However, the plasma-treated membrane still shown great hydrophilicity, and the contact angle decreased to 0 within 11 s despite the time effect. During the two rounds of 80 min of bovine serum albumin buffer solution filtration process, the fluxes of newly plasma-treated membrane and that of the membrane 3 months later decreased to 78 L m−2 h−1 and 54 L m−2 h−1, respectively, whereas the flux of the pristine membrane decreased to 12 L m−2 h−1.

scholarly journals ENHANCING HYDROPHILICITY OF POLYSULFONE MEMBRANE SURFACE BY UV IRRADIATION OF DIFFERENT WAVELENGTHS AND BY PEG GRAFTING

2021 ◽  
Vol 83 (4) ◽  
pp. 111-117
Author(s):  
Soraya Ruangdit ◽  
Suksawat Sirijaruku ◽  
Thawat Chittrakarn ◽  
Chaiporn Kaew-on
Keyword(s):  
Contact Angle ◽  
Membrane Surface ◽  
Water Flux ◽  
Separation Performance ◽  
Poly Ethylene Glycol ◽  
Uv Treatment ◽  
Water Contact ◽  
Polysulfone Membrane ◽  
Membrane Surfaces ◽  
Poly Ethylene

Polysulfone polymer (PSF) membrane has disadvantages due to its hydrophobicity, which may cause fouling and reduce separation performance. Therefore, this study aimed to enhance the hydrophilicity of PSF membranes by using irradiation at different ultraviolet (UV) wavelengths, followed by Poly(ethylene glycol) (PEG) grafting on the PSF surfaces. The hydrophilicity of the treated membrane surfaces was examined by measuring water contact angle (WCA), surface energy (SE), surface morphology, functional groups, salt rejection, and water flux in a filtration instrument. The results show that with long UV treatment for up to 72 h, the 312 nm wavelength gave lesser WCA than treatment at 254 nm. The treated PSF membrane irradiated at 312 nm for 72 h, followed by PEG grafting, was effectively improved and retained increased hydrophilicity for up to thirty days.

scholarly journals Advantages and Limitations of Surface Analysis Techniques on Plasma-Treated Arabidopsis thaliana Seeds

2021 ◽  
Vol 8 ◽  
Author(s):  
Alexandra Waskow ◽  
Alan Howling ◽  
Ivo Furno
Keyword(s):  
Contact Angle ◽  
Arabidopsis Thaliana ◽  
Surface Analysis ◽  
Photoelectron Spectroscopy ◽  
Surface Characterization ◽  
Attenuated Total Reflection ◽  
X Ray ◽  
Force Microscopy ◽  
Analysis Techniques ◽  
Surface Analysis Techniques

Surface characterization of plasma-treated seeds has made significant progress over the last decade. Most papers in the literature use scanning electron microscopy (SEM) and contact angle goniometry to investigate surface modifications. However, very few papers address the chemical modifications to the seed coat after plasma treatment. Here, a summary of the methods used to analyze plasma-treated seeds is presented, such as SEM, contact angle goniometry, energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). The results obtained on Arabidopsis thaliana Col-0 seeds and the limitations of these techniques are discussed. An experiment was designed in order to compare the relative advantages and limitations of these surface analysis techniques by investigating the separate effects of plasma, heat, and ozone on A. thaliana seeds.

scholarly journals Improving Wettability: Deposition of TiO2 Nanoparticles on the O2 Plasma Activated Polypropylene Membrane

2019 ◽  
Vol 20 (13) ◽  
pp. 3309 ◽  
Author(s):  
Babak Jaleh ◽  
Ehsan Sabzi Etivand ◽  
Bahareh Feizi Mohazzab ◽  
Mahmoud Nasrollahzadeh ◽  
Rajender S. Varma
Keyword(s):  
Tio2 Nanoparticles ◽  
Photoelectron Spectroscopy ◽  
Membrane Surface ◽  
Polymer Surface ◽  
Sample Surface ◽  
Dip Coating ◽  
Attenuated Total Reflection ◽  
Water Contact ◽  
X Ray ◽  
O2 Plasma

Radio frequency plasma is one of the means to modify the polymer surface namely in the activation of polypropylene membranes (PPM) with O2 plasma. Activated membranes were deposited with TiO2 nanoparticles by the dip coating method and the bare sample and modified sample (PPM5-TiO2) were irradiated by UV lamps for 20–120 min. Characterization techniques such as X-ray diffraction (XRD), Attenuated total reflection technique- Fourier transform infrared spectroscopy (ATR-FTIR), Thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), Scanning electron microscope (SEM) and water contact angle (WCA) measurements were applied to study the alteration of ensuing membrane surface properties which shows the nanoparticles on the sample surface including the presence of Ti on PPM. The WCA decreased from 135° (PPM) to 90° (PPM5-TiO2) and after UV irradiation, the WCA of PPM5-TiO2 diminished from 90° to 40°.

TEMPO-Mediated Oxidation of Bacterial Cellulose in Buffer Solution

2014 ◽  
Vol 789 ◽  
pp. 90-94 ◽  
Author(s):  
Chuan Lu ◽  
Shi Yan Chen ◽  
Yi Zheng ◽  
Wei Li Zheng ◽  
Cao Xiang ◽  
...  
Keyword(s):  
Bacterial Cellulose ◽  
Attenuated Total Reflection ◽  
Original Structure ◽  
Hydroxyl Groups ◽  
X Ray Diffraction ◽  
Buffer Solution ◽  
Carboxyl Content ◽  
X Ray ◽  
Structures And Properties ◽  
Mediated Oxidation

Oxidized bacterial cellulose (BC) was prepared in Na2CO3-NaHCO3buffer solution using NaClO as a primary oxidant with catalytic amounts of 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO) and NaBr at pH 10.5. Ethylenediamine was used as activators to pretreat BC in order to increase the accessibility of primary hydroxyl groups. The structures and properties of oxidized BC were characterized by attenuated total reflection infrared spectroscopy (ATR-IR), elemental analysis (EA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results indicate that the reformative oxidation successfully introduces carboxyl groups into BC, and the carboxyl content was found to be 1.34mmol per gram cellulose, higher than that of BC without pretreatment (0.81 mmol/g carboxyl introduced) under the same condition. In addition, the oxidized BC maintained the original structure which could expand the application of BC.

scholarly journals Hydrophobic Modification of Graphene Oxide and Its Effect on the Corrosion Resistance of Silicone-Modified Epoxy Resin

Metals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 89
Author(s):  
Wei Yuan ◽  
Qian Hu ◽  
Jiao Zhang ◽  
Feng Huang ◽  
Jing Liu
Keyword(s):  
Contact Angle ◽  
Corrosion Resistance ◽  
Graphene Oxide ◽  
Physical Properties ◽  
Epoxy Resin ◽  
Electrochemical Impedance ◽  
Salt Spray ◽  
X Ray ◽  
Modified Graphene Oxide ◽  
Modified Epoxy

This study modified graphene oxide (GO) with hydrophilic octadecylamine (ODA) via covalent bonding to improve its dispersion in silicone-modified epoxy resin (SMER) coatings. The structural and physical properties of ODA-GO were characterized by field-emission scanning electron microscopy (FE-SEM), X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and contact angle tests. The ODA-GO composite materials were added to SMER coatings by physical mixing. FE-SEM, water absorption, and contact angle tests were used to evaluate the physical properties of the ODA-GO/SMER coatings, while salt spray, electrochemical impedance spectroscopy (EIS), and scanning Kelvin probe (SKP) methods were used to test the anticorrosive performance of ODA-GO/SMER composite coatings on Q235 steel substrates. It was found that ODA was successfully grafted onto the surfaces of GO. The resulting ODA-GO material exhibited good hydrophobicity and dispersion in SMER coatings. The anticorrosive properties of the ODA-GO/SMER coatings were significantly improved due to the increased interfacial adhesion between the nanosheets and SMER, lengthening of the corrosive solution diffusion path, and increased cathodic peeling resistance. The 1 wt.% ODA-GO/SMER coating provided the best corrosion resistance than SMER coatings with other amounts of ODA-GO (including no addition). After immersion in 3.5 wt.% NaCl solution for 28 days, the low-frequency end impedance value of the 1 wt.% ODA-GO/SMER coating remained high, at 6.2 × 108 Ω·cm2.

scholarly journals Diethylstilbestrol Modifies the Structure of Model Membranes and Is Localized Close to the First Carbons of the Fatty Acyl Chains

Biomolecules ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 220
Author(s):  
Alessio Ausili ◽  
Inés Rodríguez-González ◽  
Alejandro Torrecillas ◽  
José A. Teruel ◽  
Juan C. Gómez-Fernández
Keyword(s):  
Membrane Surface ◽  
Water Layer ◽  
Fatty Acyl ◽  
31P Nmr Spectroscopy ◽  
Relaxation Rates ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Acyl Chains ◽  
Dynamics Simulations

The synthetic estrogen diethylstilbestrol (DES) is used to treat metastatic carcinomas and prostate cancer. We studied its interaction with membranes and its localization to understand its mechanism of action and side-effects. We used differential scanning calorimetry (DSC) showing that DES fluidized the membrane and has poor solubility in DMPC (1,2-dimyristoyl-sn-glycero-3-phosphocholine) in the fluid state. Using small-angle X-ray diffraction (SAXD), it was observed that DES increased the thickness of the water layer between phospholipid membranes, indicating effects on the membrane surface. DSC, X-ray diffraction, and 31P-NMR spectroscopy were used to study the effect of DES on the Lα-to-HII phase transition, and it was observed that negative curvature of the membrane is promoted by DES, and this effect may be significant to understand its action on membrane enzymes. Using the 1H-NOESY-NMR-MAS technique, cross-relaxation rates for different protons of DES with POPC (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine) protons were calculated, suggesting that the most likely location of DES in the membrane is with the main axis parallel to the surface and close to the first carbons of the fatty acyl chains of POPC. Molecular dynamics simulations were in close agreements with the experimental results regarding the location of DES in phospholipids bilayers.

scholarly journals Silver Nanoparticles from Oregano Leaves’ Extracts as Antimicrobial Components for Non-Infected Hydrogel Contact Lenses

2021 ◽  
Vol 22 (7) ◽  
pp. 3539
Author(s):  
Anastasia Meretoudi ◽  
Christina N. Banti ◽  
Panagiotis K. Raptis ◽  
Christina Papachristodoulou ◽  
Nikolaos Kourkoumelis ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Contact Lenses ◽  
Attenuated Total Reflection ◽  
Bacterial Strains ◽  
Scanning Calorimetry ◽  
X Ray ◽  
E Coli ◽  
Polymer Hydrogels ◽  
20 Nm ◽  
And Staphylococcus Aureus

The oregano leaves’ extract (ORLE) was used for the formation of silver nanoparticles (AgNPs(ORLE)). ORLE and AgNPs(ORLE) (2 mg/mL) were dispersed in polymer hydrogels to give the pHEMA@ORLE_2 and pHEMA@AgNPs(ORLE)_2 using hydroxyethyl–methacrylate (HEMA). The materials were characterized by X-ray fluorescence (XRF) spectroscopy, X-ray powder diffraction analysis (XRPD), thermogravimetric differential thermal analysis (TG-DTA), derivative thermogravimetry/differential scanning calorimetry (DTG/DSC), ultraviolet (UV-Vis), and attenuated total reflection mode (ATR-FTIR) spectroscopies in solid state and UV–Vis in solution. The crystallite size value, analyzed with XRPD, was determined at 20 nm. The antimicrobial activity of the materials was investigated against Gram-negative bacterial strains Pseudomonas aeruginosa (P. aeruginosa) and Escherichia coli (E. coli). The Gram-positive ones of the genus of Staphylococcus epidermidis (S. epidermidis) and Staphylococcus aureus (S. aureus) are known to be involved in microbial keratitis by the means of inhibitory zone (IZ), minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC). The IZs, which developed upon incubation of P. aeruginosa, E. coli, S. epidermidis, and S. aureus with paper discs soaked in 2 mg/mL of AgNPs(ORLE), were 11.7 ± 0.7, 13.5 ± 1.9, 12.7 ± 1.7, and 14.3 ± 1.7 mm. When the same dose of ORLE was administrated, the IZs were 10.2 ± 0.7, 9.2 ± 0.5, 9.0 ± 0.0, and 9.0 ± 0.0 mm. The percent of bacterial viability when they were incubated over the polymeric hydrogel discs of pHEMA@AgNPs(ORLE)_2 was interestingly low (66.5, 88.3, 77.7, and 59.6%, respectively, against of P. aeruginosa, E. coli, S. epidermidis, and S. aureus) and those of pHEMA@ORLE_2 were 89.3, 88.1, 92.8, and 84.6%, respectively. Consequently, pHEMA@AgNPs(ORLE)_2 could be an efficient candidate toward the development of non-infectious contact lenses.

scholarly journals New Synthetic Methods of Novel Nanoporous Polycondensates and Excellent Oxygen Permselectivity of Their Composite Membranes

Nanomaterials ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 859
Author(s):  
Yu Zang ◽  
Toshiki Aoki ◽  
Masahiro Teraguchi ◽  
Takashi Kaneko ◽  
Hongge Jia ◽  
...  
Keyword(s):  
Contact Angle ◽  
Upper Bound ◽  
Oxygen Permeability ◽  
Membrane Surface ◽  
Composite Membranes ◽  
Synthetic Methods ◽  
Preparation Methods ◽  
First Time

Two kinds of novel nanoporous polycondensates (sc(Rf)) have been synthesized by two new preparation methods consisting of polycondensation and highly selective photocyclicaromataization of 1/3 helical cis-cis polyphenylacetylenes with polymerizable groups. By the original methods, new well-defined sheet polymers having nanopores or nanospaces have been synthesized for the first time. Their composite membranes, containing small amounts (1.0 wt%) of sc(Rf), had ultrahigh oxygen permeability (Po2 > 1000 barrer), and their plots were beyond the Robeson’s upper bound line in the graph of oxygen permselectivity (α = Po2/PN2) versus Po2. Both α and Po2 values were enhanced by adding only small amounts (1.0 wt%) of sc(Rf). One of the sc(Rf)s synthesized on the base membrane surface showed the best performance, i.e., Po2 = 5300 barrer and α = 2.5. The membrane surface was effectively covered by sc(Rf), judging from the contact angle values. It is thought that nanopores and nanospaces created in and between sc(Rf) molecules played an important role for the enhancement of both α and Po2/PN2.

Sign in / Sign up

Export Citation Format

Share Document