可食包装膜与合成包装膜综合性质的对比研究

研究了几种可食包装膜和合成包装膜的综合性质。结果表明:明胶膜、海藻酸钠复合膜和甲基纤维素复合膜综合性质较好。明胶膜的直角撕裂强度和断裂伸长率高于低密度聚乙烯膜(LDPE膜)和高密度聚乙烯膜(HDPE膜),但其抗拉强度稍低于HDPE膜而高于LDPE膜;海藻酸钠复合膜和甲基纤维素复合膜的抗拉强度高于HDPE膜和LDPE膜,海藻酸钠复合膜的直角撕裂强度和断裂伸长率以及甲基纤维素复合膜的断裂伸长率低于LDPE膜和HDPE膜,但甲基纤维素复合膜的直角撕裂强度却高于LDPE膜和HDPE膜;这3种膜都具有热封性,其热封强度接近HDPE膜,并具较高的阻气、阻油和阻湿性能,可以满足一些食品的包装要求。

A Contrast Study on Comprehensive Properties of Edible Packing Film and Synthetical Plastics Film

The comprehensive properties of edible packing film and the synthetical plastics film were investigated in this paper. The results indicated that the comprehensive properties of gelatin film and compound alginate film and compound methylcellulose film were better than those of other edible films. The tangential breaking strength and breaking elongation rate of gelatin film was higher than that of low density polyethylene (LDPE) film and high density polyethylene (HDPE) film, but its tensile strength was lower than that of HDPE film, higher than that of LDPE film. The tensile strength of the compound alginate film and the compound methylcellulose film was stronger than that of LDPE film and HDPE film. The tangential breaking strength and the breaking elongation rate of compound alginate film and the breaking elongation rate of compound methylcellulose film was lower than that of LDPE film and HDPE film. However, the tangential breaking strength of compound methylcellulose film was stronger than that of LDPE film and HDPE film. The three films with heatsealing, whose strength was close to that of HDPE film and with high abilities to inhibit the permeance of air and oil and moisture, could meet the demand for some food packing.