Film preparation
Film formulations were prepared by blending low density
polyethylene with 2% (w/w) chitosan or PEGylated chitosanpowder followed by compression molding. Blending was
performed in a pilot two-screw Brabender extruder machine
(Brabender) operated at 190 8C for 10 min at a torque of 1 kg. PE
and chitosan or PEGylated chitosan were manually mixed and
ground before entering the compounder.
Approximately 4.3 g of compound were inserted into a
12.5 cm 7.5 cm brass mold, heated gradually to 180 8C, and
compressed at a pressure of 20 ton for 5 min, followed by
gradual cooling to room temperature.