| Yazarlar |
Yahya Akgöl
|
|
Christian Hofmann
|
Yunus KARATAŞ
Ahi Evran Üniversitesi, Türkiye |
|
Cornelia Cramer
|
|
Hans Dieter Wiemhöfer
|
|
M Schönhoff
|
| Özet |
| Polyelectrolyte multilayers are built up from ionically modified polyphosphazenes by layer-by-layer assembly of a cationic (poly[bis(3-amino-N,N, N-trimethyl-l-propanaminium iodide)phosphazene] (PAZ+) and an anionic poly[bis(lithium carboxylatophenoxy)phosphazene] (PAZ-). In comparison, multilayers of poly(sodium 4-styrenesulfonate) (PSS) and poly(allylamine hydrochloride) (PAH) are investigated. Frequency-dependent conductivity spectra are taken in sandwich geometry at controlled relative humidity. Conductivity spectra of ion-conducting materials generally display a dc plateau at low frequencies and a dispersive regime at higher frequencies. In the present case, the dispersive regime shows a frequency dependence, which is deviating from the typical behavior found in most ion-conducting materials. Dc conductivity values, which can be attributed to long-range ionic transport, are on the order of σdc = 10-10-10-7 S·cm-1 and strongly depend on relative humidity. For PAZ +/PAZ- multilayers σdc is consistently larger by one decade as compared to PSS/PAH layers, while the humidity dependence is similar, pointing at general mechanisms. A general law of a linear dependence of log(σdc) on relative humidity is found over a wide range of humidity and holds for both multilayer systems. This very strong dependence was attributed to variations of the ion mobility with water content, since the water content itself is not drastically dependent on humidity. © 2007 American Chemical Society. |
| Anahtar Kelimeler |
| Bildiri Türü | Tebliğ/Bildiri |
| Bildiri Alt Türü | Poster Olarak Sergilenen Tebliğ (Uluslararası Kongre/Sempozyum) |
| Bildiri Niteliği | Alanında Hakemli Uluslararası Kongre/Sempozyum |
| Bildiri Dili | İngilizce |
| Kongre Adı | 21st Conference of the European Colloid and InterfaceSociety |
| Kongre Tarihi | 10-09-2007 / 14-09-2007 |
| Basıldığı Ülke | İsviçre |
| Basıldığı Şehir | Cenevre |
| Atıf Sayıları | |
| SCOPUS | 54 |
