Single molecule tracking studies of lower critical solution temperature transition behavior in poly(N-isopropylacrylamide)
© 2011 American Chemical Society
| Veröffentlicht in: | Langmuir : the ACS journal of surfaces and colloids. - 1992. - 27(2011), 17 vom: 06. Sept., Seite 11037-43 |
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| 1. Verfasser: | |
| Weitere Verfasser: | , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2011
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| Zugriff auf das übergeordnete Werk: | Langmuir : the ACS journal of surfaces and colloids |
| Schlagworte: | Journal Article Research Support, U.S. Gov't, Non-P.H.S. Acrylamides Acrylic Resins Polymers Solutions poly-N-isopropylacrylamide 25189-55-3 |
| Zusammenfassung: | © 2011 American Chemical Society Spatial and temporal heterogeneities in expanded and collapsed surface bound poly(N-isopropylacrylamide), pNIPAAm, films are studied by single molecule tracking (SMT) experiments. Tracking data are analyzed using both radius of gyration (R(g)) evolution and confinement level calculations to elucidate the range of behaviors displayed by single Rhodamine6G (R6G) molecules. Confined diffusion that is dictated by the free volume within surface tethered chains is observed with considerable dispersion among individual R6G molecules. Thus, the distribution of probe behavior reflects nanometer-scale information about the behavior of the probe-polymer system at temperatures above (T > T(LCST)) and below (T < T(LCST)) the lower critical solution temperature (LCST). In this context, confinement-level analysis and R(g) evolution both show a larger degree of confinement of the probe in pNIPAAm at T > T(LCST). Temperature-dependent changes in confinement are evidenced at T > T(LCST) by a higher percentage of confined steps, longer periods of confined events, and smaller area of confined zones, as well as a shift in the overall distribution of R(g) evolution paths and final R(g) distributions |
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| Beschreibung: | Date Completed 29.12.2011 Date Revised 20.11.2014 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1520-5827 |
| DOI: | 10.1021/la201753v |