@article{DiehlCernochZenkeetal.2010,
  author    = {Diehl, Christina and Cernoch, Peter and Zenke, Ingrid and Runge, Heike and Pitschke, Rona and Hartmann, Juergen and Tiersch, Brigitte and Schlaad, Helmut},
  title     = {Mechanistic study of the phase separation/crystallization process of poly(2-isopropyl-2-oxazoline) in hot water},
  issn      = {1744-683X},
  doi       = {10.1039/C0sm00114g},
  year      = {2010},
  abstract  = {The kinetics of the crystallization of thermoresponsive poly(2-isopropyl-2-oxazoline) in water and the time- dependent evolution of the morphology were examined using wide-angle X-ray scattering and conventional and cryogenic scanning electron microscopy. Results indicate that a temperature-induced phase separation produces a bicontinuous polymer network-like structure, which with the onset of crystallization collapses into individual particles (1-2 mu m in diameter) composed of a porous fiber mesh. Nanofibers then preferentially form at the particle surface, thus wrapping the microspheres like a ball of wool. The particle morphology is severely affected by changes in temperature and less by the initial polymer concentration.},
  language  = {en}
}
@article{ShkilnyyGraefHiebletal.2009,
  author    = {Shkilnyy, Andriy and Gr{\"a}f, Ralph and Hiebl, Bernhard and Neffe, Axel T. and Friedrich, Alwin and Hartmann, Juergen and Taubert, Andreas},
  title     = {Unprecedented, low cytotoxicity of spongelike calcium phosphate/poly(ethylene imine) hydrogel composites},
  issn      = {1616-5187},
  doi       = {10.1002/mabi.200800266},
  year      = {2009},
  abstract  = {Covalently crosslinked PEI hydrogels are efficient templates for calcium phosphate mineralization in SBF. In contrast to the PEI hydrogels, non-crosslinked PEI does not lead to calcium phosphate nucleation and growth in SBF. The precipitate is a mixture of brushite and hydroxyapatite. The PEI/calcium phosphate composite material exhibits a sponge like morphology and a chemical composition that is interesting for implants. Cytotoxicity tests using Dictyostelium discoideum amoebae show that both the non-mineralized and mineralized hydrogels have a very low cytotoxicity. This suggests that next generation PEI hydrogels, where also the degradation products are non-toxic, could be interesting for biomedical applications.},
  language  = {en}
}