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| Titel: |
Polymer Films from Size Exclusion Chromatography Using A Solvent-Evaporation Interface: Analysis of Polymer Blends |
| Auteur: |
Cheung, P. C. Hsu, S. Tempel, M. Balke, S. T. Schunk, T. C. Li, L. Sosnowski, S. Winnik, M. A. |
| Verschenen in: |
International journal of polymer analysis & characterization |
| Paginering: | Jaargang 2 (1996) nr. 3 pagina's 271-291 |
| Jaar: |
1996-04-01 |
| Inhoud: |
Two solvent-evaporation interfaces were used for high-temperature and room-temperature size exclusion chromatography (SEC) to deposit fractions as dried polymer films on substrates. In the high-temperature SEC work, polymers of interest included polyethylene labeled with a fluorescent dye (4-nitrobenzo-2-oxa-1,3-diazole (NBD)), unlabeled polystyrene, unlabeled polypropylene, both individually and as blends of these polymers. Fourier-transform infrared (FTIR) spectroscopy, optical microscopy, laser confocal fluorescence microscopy, and fluorescence spectroscopy were used to analyze the films. FTIR spectroscopy results were readily affected by film morphologies. Resulting spectral inaccuracies included Christiansen distortion, wavy baselines, and changes in absorption band ratios. Laser confocal fluorescence microscopy results proved especially misleading with some labeled polyethylene failing to fluoresce. NBD-labeled poly(methyl methacrylate), unlabeled poly(methyl methacrylate), unlabeled polystyrene, NBD-labeled polystyrene, as well as blends of these polymers were analyzed using the room temperature SEC-evaporation interface system. No phase separation was observed in those blends. However, in an SEC run of phenanthrene-labeled polystyrene and anthracene-labeled poly(methyl methacrylate), steady-state fluorescence spectra did reveal the increasing diffuseness of the polymer-polymer interface as molecular size of the polymer blend components decreased. |
| Uitgever: |
Taylor & Francis |
| Bronbestand: |
Elektronische Wetenschappelijke Tijdschriften |
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