Influence of a hydrophobic core on thermoresponsive behavior of dendrimer-based star-shaped poly(2-isopropyl-2-oxazoline) in aqueous solutions

  • Alina Amirova
  • Serafim Rodchenko
  • Sergey Milenin
  • Elena Tatarinova
  • Mikhail Kurlykin
  • Andrey Tenkovtsev
  • Alexander Filippov


The behavior of eight-arm, star-shaped poly(2-isopropyl-2-oxazoline) (PiPrOx8) with a hydrophobic dendrimer core was studied in aqueous solutions by light scattering and turbidimetry methods. In order to reveal the influence of the star-shaped structure, model linear PiPrOxs were investigated for comparison. The experiments were carried out within a 100-fold concentration interval at temperatures from 15 to 63 °C. Dendrimer core interaction lead to the formation of different types of aggregates at low temperatures as compared to star-shaped PiPrOx with different cores. The temperatures of the phase separation interval were determined and analyzed depending on concentration. It was shown that macromolecule shrinkage and aggregation occur below the phase separation onset which results from the specific chemical nature of macromolecules and their hydrophilic-hydrophobic balance.


Thermosensitive polymer Poly(2-isopropyl-2-oxazolines) Phase separation Star polymers Solution properties 



The financial support was provided by the Russian Foundation for Basic Research (project no. 15-33-20693-mol_a_ved) and the Russian Science Foundation (no. 16-13-10521).

Supplementary material

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Copyright information

© Springer Science+Business Media B.V. 2017

Authors and Affiliations

  1. 1.Institute of Macromolecular Compounds of Russian Academy of SciencesSt. PetersburgRussia
  2. 2.Saint Petersburg National Research University of Information TechnologiesSt. PetersburgRussia
  3. 3.Enikolopov Institute of Synthetic Polymeric Materials of Russian Academy of SciencesMoscowRussia

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