Interfacial and fluorescence studies on stereoblock poly(N-isopropylacryl amide)s

Aqueous solution and water-air interfacial properties of associative thermally responsive A-B-A stereoblock poly(N-isopropylacryl amide), PNIPAM, polymers were studied and compared to atactic PNIPAM. The A-B-A polymers consist of atactic PNIPAM as a hydrophilic block (either A or B) and a water-inso...

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Veröffentlicht in:Langmuir : the ACS journal of surfaces and colloids. - 1992. - 28(2012), 41 vom: 16. Okt., Seite 14792-8
1. Verfasser: Niskanen, Jukka (VerfasserIn)
Weitere Verfasser: Wu, Cynthia, Ostrowski, Maggie, Fuller, Gerald G, Tenhu, Heikki, Hietala, Sami
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2012
Zugriff auf das übergeordnete Werk:Langmuir : the ACS journal of surfaces and colloids
Schlagworte:Journal Article Research Support, Non-U.S. Gov't Acrylamides Acrylic Resins Polymers poly-N-isopropylacrylamide 25189-55-3
Beschreibung
Zusammenfassung:Aqueous solution and water-air interfacial properties of associative thermally responsive A-B-A stereoblock poly(N-isopropylacryl amide), PNIPAM, polymers were studied and compared to atactic PNIPAM. The A-B-A polymers consist of atactic PNIPAM as a hydrophilic block (either A or B) and a water-insoluble block of isotactic PNIPAM. The surface tensions of aqueous PNIPAM solutions were measured as a function of both temperature and concentration. The isotactic blocks did not have an effect on the surface activity of the solutions. Rheological measurements on the water-air interface showed that the aggregated PNIPAMs containing isotactic blocks increased the elasticity of the surface significantly as compared to the atactic reference upon heating. Two fluorescence probes, pyrene and (4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (4HP), added to the aqueous polymer solutions were concluded to reside in surroundings with lower polarity and increased microviscosity in cases when the polymers contained isotactic blocks, as compared to ordinary atactic polymers
Beschreibung:Date Completed 06.03.2013
Date Revised 20.11.2014
published: Print-Electronic
Citation Status MEDLINE
ISSN:1520-5827
DOI:10.1021/la302468j