• Medientyp: E-Artikel
  • Titel: Nanostructural changes in crystallizable controlling units determine the temperature-memory of polymers
  • Beteiligte: Nöchel, Ulrich [VerfasserIn]; Reddy, Chaganti Srinivase [VerfasserIn]; Wang, Ke [VerfasserIn]; Cui, Jing [VerfasserIn]; Zizak, Ivo [VerfasserIn]; Behl, Marc [VerfasserIn]; Kratz, Karl [VerfasserIn]; Lendlein, Andreas [VerfasserIn]
  • Körperschaft: Technische Universität Hamburg-Harburg ; Technische Universität Hamburg-Harburg, Institut für Werkstoffphysik und -technologie
  • Erschienen: 2015
  • Erschienen in: Journal of materials chemistry / A ; 3(2015), 16, Seite 8284-8293
  • Sprache: Englisch
  • DOI: 10.15480/882.2352; 10.1039%2Fc4ta06586g
  • ISSN: 2050-7496
  • Identifikator:
  • Entstehung:
  • Anmerkungen: Sonstige Körperschaft: Technische Universität Hamburg-Harburg
    Sonstige Körperschaft: Institut für Werkstoffphysik und Technologie
  • Beschreibung: Temperature-memory polymers remember the temperature, where they were deformed recently, enabled by broad thermal transitions. In this study, we explored a series of crosslinked poly[ethylene-co-(vinyl acetate)] networks (cPEVAs) comprising crystallizable polyethylene (PE) controlling units exhibiting a pronounced temperature-memory effect (TME) between 16 and 99 °C related to a broad melting transition (∼100 °C). The nanostructural changes in such cPEVAs during programming and activation of the TME were analyzed via in situ X-ray scattering and specific annealing experiments. Different contributions to the mechanism of memorizing high or low deformation temperatures (T<inf>deform</inf>) were observed in cPEVA, which can be associated to the average PE crystal sizes. At high deformation temperatures (>50 °C), newly formed PE crystals, which are established during cooling when fixing the temporary shape, dominated the TME mechanism. In contrast, at low T<inf>deform</inf> (<50 °C), corresponding to a cold drawing scenario, the deformation led preferably to a disruption of existing large crystals into smaller ones, which then fix the temporary shape upon cooling. The observed mechanism of memorizing a deformation temperature might enable the prediction of the TME behavior and the knowledge based design of other TMPs with crystallizable controlling units.
  • Zugangsstatus: Freier Zugang