F. Debeaufort et A. Voilley, METHYLCELLULOSE-BASED EDIBLE FILMS AND COATINGS .1. MECHANICAL AND THERMAL-PROPERTIES AS A FUNCTION OF PLASTICIZER CONTENT, Journal of agricultural and food chemistry, 45(3), 1997, pp. 685-689
Several edible films based on methylcellulose and polyethylene glycol
400 (PEG400) were prepared and stored until equilibration at different
relative humidities. Tensile stress-strain curves show very different
behaviors as a function of PEG400 and relative humidity. Tensile stre
ngth strongly depends on relative humidity and then on water content,
more than on PEG400 content. On the contrary, elongation is dependent
both on water and PEG400. These differences correspond to the glass tr
ansition of the polymer, which affects the elongation more than the te
nsile strength. However, from DSC measurements, it appears that the PE
G400 has no or a very low compatibility with the methylcellulose matri
x.