Atomic scale investigation of the volume phase transition in concentrated PNIPAM microgels.

@article{Zanatta2020AtomicSI,
  title={Atomic scale investigation of the volume phase transition in concentrated PNIPAM microgels.},
  author={Marco Zanatta and Letizia Tavagnacco and Elena Buratti and Ester Chiessi and Francesca Natali and Monica Bertoldo and Andrea Orecchini and Emanuela Zaccarelli},
  journal={The Journal of chemical physics},
  year={2020},
  volume={152 20},
  pages={
          204904
        }
}
Combining elastic incoherent neutron scattering and differential scanning calorimetry, we investigate the occurrence of the volume phase transition (VPT) in very concentrated poly-(N-isopropyl-acrylamide) (PNIPAM) microgel suspensions, from a polymer weight fraction of 30 wt. % up to dry conditions. Although samples are arrested at the macroscopic scale, atomic degrees of freedom are equilibrated and can be probed in a reproducible way. A clear signature of the VPT is present as a sharp drop in… 
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