Hier finden Sie wissenschaftliche Publikationen aus den Fraunhofer-Instituten.

Studies on the barrier performance and adhesion strength of novel barrier films for vacuum insulation panels

: Miesbauer, Oliver; Kucukpinar, Esra; Kiese, Sandra; Carmi, Yoash; Noller, Klaus; Langowski, Horst-Christian


Energy and buildings 85 (2014), pp.597-603
ISSN: 0378-7788
Journal Article
Fraunhofer IVV ()

Novel cost efficient high barrier envelopes are developed for vacuum insulation panels. In order to fulfil the required maximum oxygen permeability (at 23 °C and 50% relative humidity (RH)) of 1 × 10−14 m3(STP) m−2 day−1 Pa−1 and water vapour transmission rate (at 23 °C and 85% → 0% RH) of 1 × 10−6 kg m−2 day−1, hybrid polymeric (ORMOCER®) and aluminium barrier layers are combined. Using roll-to-roll processes, these materials are deposited from the liquid or gas phase on top of a poly(ethylene terephthalate) substrate film. The low adhesion strength observed between aluminium and ORMOCER® layers is significantly increased by the deposition of an additional aluminium oxide layer between the two materials. The lamination of a polyethylene or polypropylene sealing film does not weaken the adhesion strength. The resulting barrier structure has reached an oxygen permeability of lower than 5 × 10−14 m3(STP) m−2 day−1 Pa−1 (at 37 °C and 30% RH). Electrochemical impedance spectroscopy gives evidence for a possible penetration of the ORMOCER® lacquer into the aluminium oxide layer (synergistic effect), which explains the improved adhesion and barrier performance due to the aluminium oxide layer.