Naslov
Gas Permeability of Uniaxially Deformed Polyethylene and Polypropylene Films

Autori
Klepac, Damir ; Galić, Kata ; Valić, Srećko

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Book of Abstracts / - Prag : International Life Sciences Institute - ILSI Europe, 2008, 187-187

Skup
4th International Symposium on Food Packaging - Scientific Developments Supporting Safety and Quality

Mjesto i datum
Prag, Češka Republika, 19.11.2008. - 21.11.2008

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
polyethylene; polypropylene; deformation; permeability; DSC; ESR

Sažetak
Polyethylene (PE) and polypropylene (PP) films were mechanically deformed at room temperature in both parallel and perpendicular directions to their initial orientations obtained during manufacturing process. The degree of deformation (λ ), defined as λ =l/lo, l and lo being the length of the deformed and relaxed sample, respectively, was varied from 1.0 to 1.4 for polyethylene and from 1.0 to 1.9 for polypropylene. Oxygen transport was investigated by manometric method and the change in the degree of crystallinity was monitored by differential scanning calorimetry (DSC). Results of manometric and DSC measurements were compared with the free volume measurements carried out by electron spin resonance (ESR). Perpendicular deformation induces a significant increase in the oxygen permeability for both PE and PP. Contrary, parallel deformation decreases the oxygen permeability through PE for λ >1.3 and does not significantly affect the oxygen permeability through PP. The degree of crystallinity increases during perpendicular deformation of PE but does not significantly change during deformation of PP. The results obtained by ESR are in good agreement with the permeability measurements.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

POVEZANOST RADA