@article{SchabBalcerzakFlakusJarczykJedrykaetal.2015,
  author    = {Schab-Balcerzak, Ewa and Flakus, Henryk and Jarczyk-Jedryka, Anna and Konieczkowska, Jolanta and Siwy, Mariola and Bijak, Katarzyna and Sobolewska, Anna and Stumpe, Joachim},
  title     = {Photochromic supramolecular azopolyimides based on hydrogen bonds},
  series = {Optical materials : an international journal on the physics and chemistry of optical materials and their applications, including devices},
  volume    = {47},
  journal   = {Optical materials : an international journal on the physics and chemistry of optical materials and their applications, including devices},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0925-3467},
  doi       = {10.1016/j.optmat.2015.06.029},
  pages     = {501 -- 511},
  year      = {2015},
  abstract  = {The approach of deriving new photoresponsive active supramolecular azopolymers based on the hydrogen bonds is described. Polymers with imide rings, i.e., poly(esterimide)s and poly(etherimide)s, with phenolic hydroxyl or carboxylic groups were applied as matrixes for the polymer dye supramolecular systems. Supramolecular films were built on the basis of the hydrogen bonds between the functional groups of the polymers and various azochromophores, that is, 4-phenylazophenol, 4-[4-(6-hydroxyhexy loxy)phenylazo]benzene, 4[4-(6-hexadecaneoxy)phenylazo]pyridine and 4-(4-hydroxyphenylazo)-pyridine. The hydrogen bonding interaction in azo-systems were studied by Fourier transform infrared spectroscopy and for selected assembles by H-1 NMR technique. The obtained polyimide azo-assembles were characterized by X-ray diffraction and DSC measurements. H-bonds allow attaching a chromophore to each repeating unit of the polymer, thereby suppressing the macroscopic phase separation except for the systems based on 4-[4-(6-hydroxyhexyloxy)phenylazo]benzene. H-bonds systems were amorphous and revealed glass transition temperatures lower than for the polyimide matrixes (170-260 degrees C). The photoresponsive behavior of the azo-assemblies was tasted in holographic recording experiment. (C) 2015 Elsevier B.V. All rights reserved.},
  language  = {en}
}
@article{DiFlorioBruendermannYadavallietal.2014,
  author    = {Di Florio, G. and Bruendermann, E. and Yadavalli, Nataraja Sekhar and Santer, Svetlana and Havenith, Martina},
  title     = {Graphene multilayer as nanosized optical strain gauge for polymer surface relief gratings},
  series = {Nano letters : a journal dedicated to nanoscience and nanotechnology},
  volume    = {14},
  journal   = {Nano letters : a journal dedicated to nanoscience and nanotechnology},
  number    = {10},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {1530-6984},
  doi       = {10.1021/nl502631s},
  pages     = {5754 -- 5760},
  year      = {2014},
  abstract  = {In this paper, we show how graphene can be utilized as a nanoscopic probe in order to characterize local opto-mechanical forces generated within photosensitive azobenzene containing polymer films. Upon irradiation with light interference patterns, photosensitive films deform according to the spatial intensity variation, leading to the formation of periodic topographies such as surface relief gratings (SRG). The mechanical driving forces inscribing a pattern into the films are supposedly fairly large, because the deformation takes place without photofluidization; the polymer is in a glassy state throughout. However, until now there has been no attempt to characterize these forces by any means. The challenge here is that the forces vary locally on a nanometer scale. Here, we propose to use Raman analysis of the stretching of the graphene layer adsorbed on top of polymer film under deformation in order to probe the strength of the material transport spatially resolved. With the well-known mechanical properties of graphene, we can obtain lower bounds on the forces acting within the film. Upon the basis of our experimental results, we can deduce that the internal pressure in the film due to grating formation can exceed 1 GPa. The graphene-based nanoscopic gauge opens new possibilities to characterize opto-mechanical forces generated within photosensitive polymer films.},
  language  = {en}
}