Aggregation Behavior of Poly(N-isopropylacrylamide) Semitelechelics with a Perfluoroalkyl Segment in Watera

✍ Scribed by Zheng Li; Samuel Oppong Kyeremateng; Keita Fuchise; Ryohei Kakuchi; Ryosuke Sakai; Toyoji Kakuchi; Jörg Kressler

• Book ID: 102940528
• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 653 KB
• Volume: 210
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.200900334

✦ Synopsis

Abstract

Two hydrophobically modified PNIPAM semitelechelics P~x~F~9~ were prepared by “clicking” PNIPAM containing an azide endgroup (P~x~N~3~) with nonadecafluoro‐1‐decyl hex‐5‐ynoate (F~9~). Micelles of P~x~F~9~ in water with a core of F~9~‐segments and a PNIPAM corona were detected by dynamic light scattering and by ^1^H and ^19^F NMR spectroscopy below the LCST. Just below the LCST, the PNIPAM chains start to collapse onto the F~9~ core followed by aggregation of several collapsed micelles to large particles in the range of ≈110 nm. The F~9~ segments shifted the LCST to lower temperatures when comparing P~x~N~3~ with P~x~F~9~. The existence of micelles in P~x~F~9~ solutions also improved the reversibility of the LCST behavior as measured by DSC.

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