| In this paper, the edible packaging films were made from pullulan as main material and with sodium alginate and sodium carboxymethylcellulose as auxiliary material.The films were determinated with thickness, tensile strength, water vapor permeability, water solubility and oxygen barrier as index. And the conditions of preparing the edible films were optimized as following: pullulan content 0.6g/25mL, sodium alginate content 0.1g/25mL, and sodium carboxymethylcellulose content 0.15/25mL, drying temperature 60℃, The physical characteristics of the edible films were tested: tensile strength 75.15MPa, elongation at break 3.46%, water vapor permeability of 1.3455×10-12g·m·(m2·s·Pa)-1, water solubility(results were expressed by solubilization time of edible films) 111s, and oxygen barrier(results were expressed by peroxide value of oil )1.41 g/100g.The compatibility of pullulan/sodium alginate/sodium carboxymethylcellulose blend films characterized by FT-IR, SEM, XRD, and ultraviolet spectrophotometer. The results indicated that there was a strong interaction and no obvious separation phenomenon between three components, so the blend films had good compatibility.Edible films needed to be sealed when used as a packaging bag. The main influence factors of sealing characteristics of pullulan/sodium alginate/sodium carboxymethylcellulose composite films were studied:sealing temperature, sealing pressure, adhesive concentration, sealing time, thickness, sealing width ect. The results indicated that the optimum preparation parameters were: sealing temperature 132℃, sealing pressure 0.4MPa, adhesive concentration 25% and sealing time 1.5s. Under these optimal conditions, the sealing strength was up to 18.09N/15mm .
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