Colloid and Polymer Science

, Volume 289, Issue 5–6, pp 699–709 | Cite as

Well defined hybrid PNIPAM core-shell microgels: size variation of the silica nanoparticle core

  • Matthias Karg
  • Stefan Wellert
  • Sylvain Prevost
  • Ralf Schweins
  • Charles Dewhurst
  • Luis M. Liz-Marzán
  • Thomas HellwegEmail author
Original Contribution


Thermoresponsive core-shell hybrid microgels with different core sizes were prepared by radical precipitation polymerization of the monomer N-isopropylacrylamide (NIPAM) in the presence of functionalized silica cores. The size of the cores was varied in a range of 70–170 nm in diameter. Characterization of the hybrid microgels was done by means of imaging techniques such as transmission electron microscopy (TEM) and atomic force microscopy (AFM). In addition, scattering techniques were used to study the swelling behavior and network structure of the responsive polymer shells. While dynamic light scattering (DLS) was employed to investigate the overall particle dimensions, SANS allowed to determine the correlation length ξ of the polymer network. Additionally, SANS also provides the average core size and the polydispersity of the cores in-situ using the method of contrast variation.


Microgel Hybrid Core-shell Silica Dynamic light scattering Small angle neutron scattering Contrast variation 



This work has been supported by the Deutsche Forschungsgemeinschaft through the priority program SPP 1259 and within the framework of the SFB840 (TP A4). M.K. is grateful to the Alexander von Humboldt foundation for a Feodor Lynen research fellowship.


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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Matthias Karg
    • 1
  • Stefan Wellert
    • 2
  • Sylvain Prevost
    • 2
  • Ralf Schweins
    • 3
  • Charles Dewhurst
    • 3
  • Luis M. Liz-Marzán
    • 4
  • Thomas Hellweg
    • 5
    Email author
  1. 1.School of Chemistry & Bio21 InstituteUniversity of MelbourneVictoriaAustralia
  2. 2.Helmholtz-Zentrum Berlin für Materialien und Energie GmbHBerlinGermany
  3. 3.Institut Laue-LangevinGrenobleFrance
  4. 4.Departamento de Quimica FisicaUniversidade de VigoVigoSpain
  5. 5.Physikalische und Biophysikalische ChemieUniversität BielefeldBielefeldGermany

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