including tensile strength, break elongation, it is reflected in the use of the product in the process of tensile capacity, if this is not qualified, in the use of food packaging bags are prone to rupture, damage phenomenon.
It also includes gas barrier indexes such as gas permeation, resistance to oil, heat, cold and dielectric, sealing and peeling of bags, pressure and fall resistance of bags, these indicators reflect the reliability of packaging protection in food packaging bags.
Plastic film bag processing must be heated this way, and plastic in the heat when there is cracking, oxidation, degradation, deterioration of the problem, therefore, in the resin processing plastic film or bag, in the resin to add antioxidants, heat stabilizer and other auxiliaries. Some packaging film bags due to the packaging process and mechanical or content requirements also require anti-static, dew-proof, Gao slippery, so also add antistatic agent, aerosol, lubricant, opening agent and other additives. All these auxiliaries, the first to be GB15139 "Food Safety Toxicology Evaluation Program" Test, proved that non-toxic can be used, but there is also a limit to add. Therefore, in the product, these can be extracted from the low molecular weight of the material, that is, evaporation residue, or can be oxidized to degenerate things, that is, potassium permanganate consumption, can not exceed the prescribed amount, more than can not be used. Therefore, the molding products also have the corresponding hygienic standards, its purpose is to prevent misuse and abuse of additives, is to better protect the direct packaging and exposure of food materials with high health and safety performance.