effect of moisture content on the physical properties

Povzetek

Regenerated cellulose-based films combined with glycerol and polyvinyl alcohol (PVOH) show interesting UV- light barrier properties, with potential application in food packaging to prevent oxidative deterioration. How- ever, these materials are sensitive to moisture, and their properties could be modified as a function of the relative humidity. Hence, the objective of the present work was to evaluate the changes in the main properties of re- generated cellulose-glycerol-PVOH films depending on the relative humidity. Using the GAB adsorption iso- therms, the moisture content was related with the water activity of the films at several relative humidity conditions. According to the obtained results, water molecules manifested a plasticizing effect modifying the mechanical, water vapour permeability and optical properties of the developed films. Tensile strength and Young’s modulus values ranged from 92.65 to 17.57 MPa and from 3639.09 to 227.89 MPa, respectively. Both of them decreased when the moisture content increased. The mechanical resistance to deformation of films enhanced at high moisture content, changing from 5.88 to 15.97% and from 0.59 to 2.97 mm in the tensile and puncture test, respectively. This effect was also observed for the burst strength. Water vapour permeability increased from 5.15⋅10?10 to 5.44⋅10?9 g/ms Pa when the moisture content increased, being more significative at higher values. No significant variations were observed in the UV-VIS transmittance at different moisture contents. The obtained results allow expanding the knowledge of the behavior of films based on regenerated cellulose.

Ključne besede

adsorption isotherms;plasticization;regenerated cellulose;water vapour permeability;

Podatki

Jezik: Angleški jezik
Leto izida:
Tipologija: 1.01 - Izvirni znanstveni članek
Organizacija: UNG - Univerza v Novi Gorici
UDK: 54
COBISS: 41885443 Povezava se bo odprla v novem oknu
ISSN: 0268-005X
Št. ogledov: 1783
Št. prenosov: 0
Ocena: 0 (0 glasov)
Metapodatki: JSON JSON-RDF JSON-LD TURTLE N-TRIPLES XML RDFA MICRODATA DC-XML DC-RDF RDF

Ostali podatki

URN: URN:SI:UNG
Vrsta dela (COBISS): Delo ni kategorizirano
Strani: str. 1-10
Zvezek: ǂVol. ǂ103
Čas izdaje: Jun. 2020
DOI: 10.1016/j.foodhyd.2020.105657
ID: 12238552
Priporočena dela:
, effect of moisture content on the physical properties
, effect of the moisture content on the barrier, mechanical and optical properties
, effect of water activity on barrier, mechanical and optical properties