Colloid and Polymer Science

, Volume 290, Issue 4, pp 297–306 | Cite as

Characterization of low molecular mass thermosensitive diblock copolymers and their self-assembly by means of analytical ultracentrifugation

  • Alvaro OrtegaEmail author
  • Ramón Pamies
  • Kaizheng Zhu
  • Anna-Lena Kjøniksen
  • Bo Nyström
  • José García de la Torre
Original Contribution


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.


Analytical 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.


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Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  • Alvaro Ortega
    • 1
    Email author
  • Ramón Pamies
    • 1
  • Kaizheng Zhu
    • 2
  • Anna-Lena Kjøniksen
    • 3
  • Bo Nyström
    • 2
  • José García de la Torre
    • 1
  1. 1.Departamento de Química-Física, Facultad de QuímicaUniversidad de MurciaMurciaSpain
  2. 2.Department of ChemistryUniversity of OsloOsloNorway
  3. 3.Department of Pharmaceutics, School of PharmacyUniversity of OsloOsloNorway

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