This study was carried out to evaluate low density polyethylene (LDPE) films,
of 180 microns thickness. when impregnated with potassium sorbate or calcium
propionate (at the concentrations of 1 ,2,3 and 4% w/w) which were processed by the
blown film extrusion process. LOPE films were examined tor their ppysical properties
(i.e. haze, gloss, waler vapor permeability, oxygen permeability, heat seatability and
shrinkability) besides, their mechanical properties (I.e. tensile strength, elongation,
slip, tear Slrength and burst slrength). Mechanical and physical proper1ies were
significantly affected by the inccrpcration of potaSSium sorbate or calcium propionate
up to 4% (wJw) in the films as their haze, Willer vapor permeability, slip and burst
strength increased. while their gloss, heat sealability, shrinkability tensile strength,
e/ongaoon, tear strength and oxygen permeability decreased as th~ concentration of
potassium sorbate or calcium propionate increased in the films. LOPf films were also
tested against some species of microorganisms on agar plate medium, from whICh it
was noticed thai, the inhibitory effect of !he films agajnslthe growth of AspergiHus
nevus, Fusarium oxysporium, Penicillium chrysogenum OSM 844 in a disk test was
higher than thai in case or BaciHus suM/is, E. cO/i and S. eureas as the concentration
of potaSl;ium sorb ate or calcium propionafe Increased up to 4%.