Characterization of low molecular mass thermosensitive diblock copolymers and their self-assembly by means of analytical ultracentrifugation
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The characterization of a series of four poly(N-isopropylacrylamide)-based copolymers with a hydrophilic block of poly(ethylene glycol) with a variable length (MPEG n -b-PNIPAAM71) has been performed by means of analytical ultracentrifugation. Molecular mass, partial specific volume, sedimentation coefficient (s), and hydrodynamic radius (R h) have been determined and successfully compared with other techniques. In addition, the self-assembly process of these four copolymers has been evaluated, finding multimeric species at temperatures lower than low critical solution temperature in the case of the longest copolymer.
KeywordsAnalytical ultracentrifugation PNIPAAM Thermoresponsive copolymers
This work was supported by grant CTQ-2009-08030 from Ministerio de Educacion y Ciencia, including FEDER funds and Fundacion Seneca-CARM. Grant no. 04531/GERM/06. A. O. is recipient of a Fundacion Cajamurcia research contract. R. P. is recipient of a Universidad de Murcia research contract. The financial support of the Norwegian Research Council through the project 177665/V30 is gratefully acknowledged.
- 3.Minko S (ed) (2006) Responsive polymer materials: design and applications. Blackwell, AmesGoogle Scholar
- 6.Price C (ed) (1982) In: Goodman I (ed) Developments in block copolymers. Applied Science, LondonGoogle Scholar
- 9.Chalal M, Ehrburger-Dolle F, Morfin I, Bley F, Aguilar de Armas MR, López Donaire ML, San Roman J, Bölgen N, Pikin E, Ziane O, Casalegno R (2010) SAXS investigation of the effect of temperature on the multiscale structure of a macroporous poly(n-isopropylacrylamide) gel. Macromolecules 43:2009–2017CrossRefGoogle Scholar
- 14.Elias HG (1977) Macromolecules, vol 1. Structure and properties. Wiley, New YorkGoogle Scholar
- 15.Mächtle W, Börger L (2006) Analytical ultracentrifugation of polymers and nanoparticles. Springer, BerlinGoogle Scholar
- 23.Schuck P (2000) Size distribution analysis of macromolecules by sedimentation velocity ultracentrifugation and Lamm equation modeling. Biophys J 178:105–120Google Scholar
- 29.Fujita H (1962) Mathematical theory of sedimentation analysis. Academic, New YorkGoogle Scholar
- 31.Sundelöf O, Nyström B (1977) Sedimentation velocity measurements in dilute and concentrated solutions of polystyrene in cyclohexane at temperatures close to and far from the consolute temperature. Chem Scr 12:162Google Scholar