Effect of Plasma Treatment on Surface Properties of Polymeric Membrane

In the present work the effect of plasma treatment has been used to improve the surface properties of polymeric membranes. The polymeric membranes of polycarbonate (PC) were synthesized using solution cast method. The plasma treatment was done in high vacuum chamber using nitrogen gas and the pressure for the plasma treatment was » 10-2 mbar. The effect of plasma treatment on surface properties like morphology, roughness, wettability and optical properties has been characterized using optical microscopy and UV-Vis spectroscopy for different time of plasma treatment.

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Temperature Dependence Study of Gas Permeability in Metal Doped Composite Polymeric Membranes

MRS Proceedings ◽

10.1557/proc-0973-bb04-16 ◽

2006 ◽

Vol 973 ◽

Author(s):

Yogesh Kumar Vijay ◽

Anil Kumar Jain ◽

Naveen Kumar Acharya ◽

Kamlendra Awasthi ◽

Vaibhav Kulshrestha

Keyword(s):

Composite Membrane ◽

Gas Permeability ◽

Gas Permeation ◽

Polymeric Membranes ◽

Plasticization Effect ◽

Optical Micrograph ◽

Solution Cast ◽

Metal Doped ◽

Increasing Temperature ◽

Solution Cast Method

ABSTRACTPolycarbonate (PC) membrane and PC based hydrogen active intermetallic compound Fe0.5Ti0.5 particles doped composite membrane have been prepared by solution cast method. The membranes have been characterized by H2 and CO2 permeability and selectivity measurements with increasing temperature. Higher gas permeation has been observed with increasing temperature. In case of doped composite membrane H2/CO2 gas pair selectivity first increases then decreases with temperature whereas in case of pure PC it decreases with temperature. The effect of doping increases the activation energies for permeation of H2 and CO2 in the doped membrane in comparison to pure PC. Doping was found to suppress plasticization effect in polycarbonate. The doped membrane was analyzed by optical micrograph and XRF study.

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Microscopic Analysis of Track Etched Polymeric Membranes

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.155.107 ◽

2009 ◽

Vol 155 ◽

pp. 107-112 ◽

Cited By ~ 1

Author(s):

N.K. Acharya

Keyword(s):

Microscopic Analysis ◽

Electronic Energy ◽

Polymeric Membranes ◽

Energetic Ions ◽

Force Microscopy ◽

High Energies ◽

Atomic Force ◽

Solution Cast ◽

Wet Chemical ◽

Solution Cast Method

The bombardment of energetic ions on polymer membranes will produce the loosely bound passage in the membrane structure due to the energy loss. The Swift Heavy Ions (SHI) creates the latent tracks of several nm surrounded by several tens of nm track halo. The tracks can be visualized under Atomic Force Microscope after wet chemical etching. In present study the polymeric membranes of 30 μm was prepared by solution cast method and irradiated by 60 MeV C+5 energetic ions. The electronic energy losses are predominant at high energies. The membranes were etched chemically to convert the tracks in to suitable pores. The Atomic Force Microscopy (AFM) gives the size and distribution of the pores. The pore size is observed in nano regime. The pore density was found to depend on the irradiation dose.

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Thin Pyrolytic Graphite Films for Electron Microscope Substrates

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065183 ◽

1971 ◽

Vol 29 ◽

pp. 226-227 ◽

Cited By ~ 1

Author(s):

George H. N. Riddle ◽

Benjamin M. Siegel

Keyword(s):

Vacuum Chamber ◽

Pyrolytic Graphite ◽

High Vacuum ◽

Dark Field ◽

Ultra High Vacuum ◽

Graphite Substrate ◽

Nickel Substrate ◽

Routine Procedure ◽

Field Electron Microscopy ◽

Dark Field Electron

A routine procedure for growing very thin graphite substrate films has been developed. The films are grown pyrolytically in an ultra-high vacuum chamber by exposing (111) epitaxial nickel films to carbon monoxide gas. The nickel serves as a catalyst for the disproportionation of CO through the reaction 2C0 → C + CO2. The nickel catalyst is prepared by evaporation onto artificial mica at 400°C and annealing for 1/2 hour at 600°C in vacuum. Exposure of the annealed nickel to 1 torr CO for 3 hours at 500°C results in the growth of very thin continuous graphite films. The graphite is stripped from its nickel substrate in acid and mounted on holey formvar support films for use as specimen substrates.The graphite films, self-supporting over formvar holes up to five microns in diameter, have been studied by bright and dark field electron microscopy, by electron diffraction, and have been shadowed to reveal their topography and thickness. The films consist of individual crystallites typically a micron across with their basal planes parallel to the surface but oriented in different, apparently random directions about the normal to the basal plane.

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The Long-Lasting Story of One Sensor Development: From Novel Ionophore Design toward the Sensor Selectivity Modeling and Lifetime Improvement

Sensors ◽

10.3390/s21041401 ◽

2021 ◽

Vol 21 (4) ◽

pp. 1401

Author(s):

Larisa Lvova ◽

Donato Monti ◽

Corrado Di Natale ◽

Roberto Paolesse

Keyword(s):

Anion Exchanger ◽

Specific Interaction ◽

Spectroscopic Studies ◽

Polymeric Membranes ◽

Polymeric Membrane ◽

Active Components ◽

Nitrite Ion ◽

Working Mechanism ◽

Axial Coordination ◽

Porphyrin Aggregation

The metalloporphyrin ligand bearing incorporated anion-exchanger fragment, 5-[4-(3-trimethylammonium)propyloxyphenyl]-10,15,20-triphenylporphyrinate of Co(II) chloride, CoTPP-N, has been tested as anion-selective ionophore in PVC-based solvent polymeric membrane sensors. A plausible sensor working mechanism includes the axial coordination of the target anion on ionophore metal center followed by the formed complex aggregation with the second ionophore molecule through positively charged anion-exchanger fragment. The UV-visible spectroscopic studies in solution have revealed that the analyte concentration increase induces the J-type porphyrin aggregation. Polymeric membranes doped with CoTPP-N showed close to the theoretical Nernstian response toward nitrite ion, preferably coordinated by the ionophore, and were dependent on the presence of additional membrane-active components (lipophilic ionic sites and ionophore) in the membrane phase. The resulting selectivity was a subject of specific interaction and/or steric factors. Moreover, it was demonstrated theoretically and confirmed experimentally that the selection of a proper ratio of ionophore and anionic additive can optimize the sensor selectivity and lifetime.

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The Growth and Characterization of Germanium-Carbon Alloy Thin Films

MRS Proceedings ◽

10.1557/proc-270-91 ◽

1992 ◽

Vol 270 ◽

Author(s):

Haojie Yuan ◽

R. Stanley Williams

Keyword(s):

Thin Films ◽

Photoelectron Spectroscopy ◽

Vacuum Chamber ◽

Optical Band Gap ◽

High Vacuum ◽

Optical Absorption Spectroscopy ◽

Alloy Thin Film ◽

New Materials ◽

X Ray

ABSTRACTThin films of pure germanium-carbon alloys (GexC1−x with x ≈ 0.0, 0.2, 0.4, 0.5, 0.6, 0.8, 1.0) have been grown on Si(100) and A12O3 (0001) substrates by pulsed laser ablation in a high vacuum chamber. The films were analyzed by x-ray θ-2θ diffraction (XRD), x-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), conductivity measurements and optical absorption spectroscopy. The analyses of these new materials showed that films of all compositions were amorphous, free of contamination and uniform in composition. By changing the film composition, the optical band gap of these semiconducting films was varied from 0.00eV to 0.85eV for x = 0.0 to 1.0 respectively. According to the AES results, the carbon atoms in the Ge-C alloy thin film samples has a bonding configuration that is a mixture of sp2 and sp3 hybridizations.

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Preparation of isotactic polypropylene (iPP) films with different top and bottom surface parts via solution cast method using decahydronaphthalene as the diluent

Polymer-Plastics Technology and Materials ◽

10.1080/25740881.2021.1888989 ◽

2021 ◽

pp. 1-12

Author(s):

Peng Zhu ◽

Bo Li ◽

Huapeng Zhang ◽

Hongwei Lu

Keyword(s):

Isotactic Polypropylene ◽

Bottom Surface ◽

Solution Cast ◽

Solution Cast Method

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Reducing the Crystallite Size of Spherulites in PEO-Based Polymer Nanocomposites Mediated by Carbon Nanodots and Ag Nanoparticles

Nanomaterials ◽

10.3390/nano9060874 ◽

2019 ◽

Vol 9 (6) ◽

pp. 874 ◽

Cited By ~ 15

Author(s):

Ranjdar Abdullah ◽

Shujahadeen Aziz ◽

Soran Mamand ◽

Aso Hassan ◽

Sarkawt Hussein ◽

...

Keyword(s):

Crystallite Size ◽

Polymer Nanocomposites ◽

Electron Transition ◽

Peak Position ◽

Carbon Nanodots ◽

Ag Nps ◽

Peak Broadening ◽

Vis Spectroscopy ◽

Solution Cast ◽

Significant Change

The PEO-based polymer nanocomposites were prepared by solution cast method. Green approaches were used for synthesis of carbon nanodots (CNDs) and silver nanoparticles (Ag NPs). It was found that the crystallite size of spherulites of PEO was greatly scarified upon incorporation of CNDs and Ag NPs. In the present work, in opposition to other studies, broadening of surface plasmon resonance (SPR) peak of metallic Ag NPs in PEO-based polymer composites was observed rather than peak tuning. Various techniques, such as powder X-ray diffraction (XRD), SEM, UV–Vis spectroscopy, and photoluminescence (PL), were used to characterize the structural, morphological, and optical properties of the samples. Increase of amorphous phase for the PEO doped with CND particles was shown from the results of XRD analyses. Upon the addition of suspended Ag NPs to the PEO:CNDs composites, significant change of XRD peak position was seen. A field-emission scanning electron microscope (FESEM) was used to investigate the surface morphology of the samples. In the SEM, a significant change in the crystalline structure was seen. The size of PEO spherulites in the PEO nanocomposite samples became smaller and the percentage of amorphous portion became larger, owing to the distribution of CNDs and Ag NPs. The UV–Vis absorption spectra of the PEO-based polymer were found to improve and shift to higher wavelengths upon incorporation of CNDs and Ag NPs into the PEO matrix. The SPR peak broadening in the UV–Vis spectra was observed in the PEO:CNDs composites due to the Ag NPs. The absorption edge value of PEO was found to shift toward lower photon energy as the CNDs and Ag NPs are introduced. The photoluminescence (PL) spectra were also observed for the PEO:CNDs and PEO:CNDs:Ag samples and found to be more intense in the PEO:CNDs system than in the PEO:CNDs:Ag system. Lastly, the optical band gap of the samples was further studied in detail using of Tauc’s model and optical dielectric loss parameter. The types of electron transition were specified.

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