Polycarbonate bottles can be used for the packaging of goods (if juice) filled at high temperatures, but polycarbonate bottles are used to hold carbonated drinks that require good barrier properties (to prevent the escape of carbon dioxide in beverages) or edible oils ( To prevent oxygen from entering the bottle so as to avoid oxidation and rancidity of the edible oil, the product cannot be well protected and the desired packaging effect cannot be obtained; and using ordinary polyester stretch bottles for packaging carbonated drinks can effectively prevent the beverage from being Carbon dioxide escape (excellent barrier properties of PET stretch bottles), which can be used in the packaging of edible oils, can delay the oxidative deterioration of edible oils and prolong their shelf life (Oxygen stretch bottles have good oxygen barrier performance and can effectively prevent The oxygen in the upper atmosphere enters the bottle through the container wall, but it is used to package goods such as high-temperature-filled fruit juices. When filled at high temperatures, the polyester stretch bottle will undergo severe deterioration and lose its use value. Polycarbonate blown bottles and ordinary polyester stretch blow molded bottles, both with extremely good transparency and gloss, are very similar in appearance, but the high temperature performance of polycarbonate bottles stands out (standing up to 120 High-temperature sterilization above °C), but poor barrier properties; while ordinary polyester stretch blow-molded bottles have good barrier properties but poor heat resistance (usually recommended at temperatures below 60°C). Another example is that polyethylene containers are resistant to acids and alkalis, but they are not resistant to many organic solvents, and nylon containers are resistant to hydrocarbons and organic solvents, but have poor acid and alkali resistance (especially poor acid resistance). Polyethylene bottles can contain substances such as acids and bases and are not suitable for containing organic solvents such as benzene and toluene (the polyethylene bottle's swelling strength is significantly reduced or organic solvents escape through the container walls), while nylon containers are not suitable for storing acids and alkalis. But it is very suitable for containing organic solvents such as benzene and xylene. The multi-layer composite container PE/PA/PE and PE single-layer containers are almost identical in appearance, and even if it is an expert in the plastics industry, it is difficult to separate them in terms of appearance, but the two containers are The difference in performance is indeed very large, especially in the barrier properties of oxygen, carbon dioxide, nitrogen, and organic solvents, can be dozens or even hundreds of times, so it must not be judged only from the appearance of plastic containers to determine its adaptability , And to grasp the basic characteristics of plastic containers, otherwise often due to improper selection of plastic containers and cause huge losses.