% IMPORTANT: The following is UTF-8 encoded.  This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.

@ARTICLE{Virtanen:860974,
      author       = {Virtanen, Otto L. J. and Kather, Michael and
                      Meyer-Kirschner, Julian and Melle, Andrea and Radulescu,
                      Aurel and Viell, Jörn and Mitsos, Alexander and Pich,
                      Andrij and Richtering, Walter},
      title        = {{D}irect {M}onitoring of {M}icrogel {F}ormation during
                      {P}recipitation {P}olymerization of {N}
                      -{I}sopropylacrylamide {U}sing in {S}itu {SANS}},
      journal      = {ACS omega},
      volume       = {4},
      number       = {2},
      issn         = {2470-1343},
      address      = {Washington, DC},
      publisher    = {ACS Publications},
      reportid     = {FZJ-2019-01607},
      pages        = {3690 - 3699},
      year         = {2019},
      abstract     = {Poly(N-isopropylacrylamide) microgels have found various
                      uses in fundamental polymer and colloid science as well as
                      in different applications. They are conveniently prepared by
                      precipitation polymerization. In this reaction, radical
                      polymerization and colloidal stabilization interact with
                      each other to produce well-defined thermosensitive particles
                      of narrow size distribution. However, the underlying
                      mechanism of precipitation polymerization has not been fully
                      understood. In particular, the crucial early stages of
                      microgel formation have been poorly investigated so far. In
                      this contribution, we have used small-angle neutron
                      scattering in conjunction with a stopped-flow device to
                      monitor the particle growth during precipitation
                      polymerization in situ. The average particle volume growth
                      is found to follow pseudo-first order kinetics, indicating
                      that the polymerization rate is determined by the
                      availability of the unreacted monomer, as the initiator
                      concentration does not change considerably during the
                      reaction. This is confirmed by calorimetric investigation of
                      the polymerization process. Peroxide initiator-induced
                      self-crosslinking of N-isopropylacrylamide and the use of
                      the bifunctional crosslinker N,N′-methylenebisacrylamide
                      are shown to decrease the particle number density in the
                      batch. The results of the in situ small-angle neutron
                      scattering measurements indicate that the particles form at
                      an early stage in the reaction and their number density
                      remains approximately the same thereafter. The overall
                      reaction rate is found to be sensitive to monomer and
                      initiator concentration in accordance with a radical
                      solution polymerization mechanism, supporting the results
                      from our earlier studies.},
      cin          = {JCNS-FRM-II / Neutronenstreuung ; JCNS-1 / IEK-10},
      ddc          = {660},
      cid          = {I:(DE-Juel1)JCNS-FRM-II-20110218 /
                      I:(DE-Juel1)JCNS-1-20110106 / I:(DE-Juel1)IEK-10-20170217},
      pnm          = {6G15 - FRM II / MLZ (POF3-6G15) / 6G4 - Jülich Centre for
                      Neutron Research (JCNS) (POF3-623)},
      pid          = {G:(DE-HGF)POF3-6G15 / G:(DE-HGF)POF3-6G4},
      experiment   = {EXP:(DE-MLZ)KWS2-20140101},
      typ          = {PUB:(DE-HGF)16},
      UT           = {WOS:000460237300134},
      doi          = {10.1021/acsomega.8b03461},
      url          = {https://juser.fz-juelich.de/record/860974},
}