Adsorption and thermoresponsive behavior of poly(N-isopropylacrylamide-co-N,N'-cystaminebisacrylamide) thin films on gold
| Autor: | Danielle D Draper, Ellane J Park, Nolan T. Flynn |
|---|---|
| Rok vydání: | 2007 |
| Předmět: |
chemistry.chemical_classification
Analytical chemistry Infrared spectroscopy Surfaces and Interfaces Polymer Quartz crystal microbalance Condensed Matter Physics Contact angle chemistry.chemical_compound Adsorption chemistry X-ray photoelectron spectroscopy Electrochemistry Poly(N-isopropylacrylamide) General Materials Science Thermoresponsive polymers in chromatography Spectroscopy |
| Zdroj: | Langmuir : the ACS journal of surfaces and colloids. 23(13) |
| ISSN: | 0743-7463 |
| Popis: | We describe the synthesis of thermoresponsive polymers made from N-isopropylacrylamide and varying amounts of a thiol-containing co-monomer, N,N'-cystaminebisacrylamide (P(NIPAm-co-CBAm)). Infrared spectroscopy revealed a backbone similar to that seen with pure PNIPAm. UV-vis spectroscopy showed that P(NIPAm-co-CBAm) undergoes a thermoresponsive phase transition around 32 degrees C in aqueous solution. The presence of the thiol groups enabled the polymer to adsorb onto gold surfaces. Following adsorption onto a gold surface, X-ray photoelectron spectroscopy showed a carbon/gold atomic ratio of 0.93 for a sample without CBAm and a ratio of 1.61 for a P(NIPAm-co-CBAm) sample with 0.20% CBAm. Quartz crystal microbalance (QCM) analysis showed increases in the mass of polymer adsorbed when the CBAm content in the polymer increased. The thermoresponsive behavior of the thin films on gold was investigated with contact angle and dissipative QCM analysis. Contact angles were measured for polymer films at both 25 and 60 degrees C. The largest temperature-induced alteration in the contact angle was seen with the 1.00% CBAm sample. Similarly, QCM-D results showed a significantly greater change in frequency and dissipation following a temperature change when CBAm was present than in pure NIPAm polymers. |
| Databáze: | OpenAIRE |
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