Oxygen plasma modification of polyurethane membranes

Date

2002-12-01

Author

Ozdemir, Y
Hasırcı, Nesrin
Serbetci, K

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

174
views

0
downloads

Polyurethane membranes were prepared under nitrogen atmosphere by using various proportions of toluene diisocyanates (TDI) and polypropylene-ethylene glycol (P) with addition of no other ingredients such as catalysts, initiator or solvent in order to achieve medical purity. Effects of composition on mechanical properties were examined. In general, modulus and UTS values demonstrated an increase and PSBR demonstrated a decrease as the TDI/Polyol ratio of the polymer increased. Elastic modulus, ultimate tensile strength (UTS) and per cent strain before rupture (PSBR) values were found to be in the range of 1.4-5.4 MPa, 0.9-1.9 MPa, and 60.4-99.7%, respectively. Surfaces of the membranes were modified by oxygen plasma applying glow-discharge technique and the effect of applied plasma power (10 W or 100 W, 15 min) on surface hydrophilicity and on the attachment of Vero cells were studied. Water contact angle values of the plasma modified surfaces varied between 67 and 46, demonstrating a decrease as the applied plasma power was increased. The unmodified material had 42-45 cells attached per cm(2). It was observed that as the applied power increased the number of attached cells first increased (60-70 cells/cm(2) at 10W) and then decreased (27-40 cells/cm(2) at 100 W). These demonstrated that surface properties of polyurethanes can be modified by plasma-glow discharge technique to achieve the optimum levels of cell attachment. (C) 2002 Kluwer Academic Publishers.

Subject Keywords

Glow-discharge, Blood-compatibility, Cell-growth, Polymer, Surfaces

URI

https://hdl.handle.net/11511/30133

Journal

JOURNAL OF MATERIALS SCIENCE-MATERIALS IN MEDICINE

DOI

https://doi.org/10.1023/a:1021185803716

Collections

Graduate School of Natural and Applied Sciences, Article

Suggestions

OpenMETU
Core

Microwave-assisted synthesis of Eu3+ doped lanthanum orthoborates, their characterizations and luminescent properties BADAN, Cansin; Esentürk, Okan; Yılmaz, Ayşen (2012-11-01) LaBO3 with various particle sizes have been successfully prepared by microwave-assisted combustion and sol-gel synthesis methods. Urea, citric acid and glycine have been used as fuels during the synthesis process. Characterizations were done by X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) Spectroscopy, Photoluminescence Excitation and Emission Spectroscopies, Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM). The SEM micrographs show dissimilar morphologies of powd...
Polybenzimidazole based nanocomposite membranes with enhanced proton conductivity for high temperature PEM fuel cells Ozdemir, Yagmur; Uregen, Nurhan; DEVRİM, YILSER (2017-01-26) In this study, phosphoric acid doped PBI nanocomposite membranes were prepared by dispersion of various amounts of inorganic nanoparticles in PBI polymer followed by phosphoric acid (H3PO4) doping for high temperature proton exchange membrane fuel cells (HT-PEMFC). All of the PBI composite membranes were cast from the same FBI polymer with the same molecular weight. Titanium dioxide (TiO2), silicon dioxide (SiO2) and inorganic proton conductor zirconium phosphate (ZrP) were used as inorganic fillers. The PB...
Nano calcium phosphates doped with titanium and fluoride ions: sinterability and stability of phases Güngör Geridönmez, Serap; Evis, Zafer; Department of Engineering Sciences (2012) The purpose of this study was to synthesize calcium phosphates doped with titanium and fluoride ions in different combinations. Pure and doped calcium phosphates were synthesized by a precipitation method. The synthesized materials were sintered at 1100ºC and 1300ºC for 1h. The ceramics were characterized by density measurements to determine the effect of sintering temperature. Presence of phases and bonds were characterized by XRD diffraction and FTIR spectroscopy. Grain sizes of the samples were obtained ...
Ethylene and acetaldehyde production by selective oxidation of ethanol using mesoporous V-MCM-41 catalysts Gucbilmez, Yesim; Doğu, Timur; Balci, Suna (2006-05-10) Vanadium-incorporated MCM-41 type catalytic materials, which were synthesized by a direct hydrothermal synthesis procedure, showed very high activity and high selectivity in the production of ethylene from ethanol in an oxidative process. Ethylene selectivity showed a significant increase with an increase in temperature over 300 degrees C, while relatively high acetaldehyde selectivities were observed at lower temperatures. An ethylene yield value of 0.66 obtained at 400 degrees C with an O-2/ethanol feed r...
Microstructural, biological and mechanical investigations of hydroxyapatite-β-tricalcium phosphate composites doped with strontium and fluoride Pourreza, Elmira; Evis, Zafer; Department of Engineering Sciences (2016) The aim of this study was to investigate the microstructure, mechanical and biological properties of biphasic hydroxyapatite--Tricalcium phosphate (HT) and HT substituted with constant fluoride (F−) and varying strontium (Sr2+) amounts. All the samples were synthesized via precipitation method and sintered at 1100°C for 1 h. It was observed that the relative density of the sintered strontium and fluoride doped HT slightly increased. For microstructural analysis, X-ray diffraction (XRD), scanning electron m...

Citation Formats

Y. Ozdemir, N. Hasırcı, and K. Serbetci, “Oxygen plasma modification of polyurethane membranes,” JOURNAL OF MATERIALS SCIENCE-MATERIALS IN MEDICINE, pp. 1147–1151, 2002, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/30133.