This little recycling logo on the bottom of plastic products is like a small ID card for each plastic container. They are made of different materials and have different uses.
"01"-pet (polyethylene terephthalate)
Mineral water bottles and carbonated beverage bottles are made of this material. Beverage bottles cannot be recycled with hot water. This material is heat-resistant to 70℃ and is only suitable for warm or frozen drinks. When filled with high-temperature liquid or heated, it is easy to deform, and some harmful substances are dissolved out. Moreover, scientists have found that this plastic product may release carcinogens after 10 months, which is toxic to human body. Therefore, drink bottles should be discarded when they are used up. They should not be used as drinking cups or as storage containers for other items, so as not to cause health problems.
PET was originally used as man-made fiber, film, adhesive tape, etc. , only used for beverage bottles in 1976. PET is used as a filling container, commonly known as "Potter bottle". Baote bottle has excellent hardness and toughness, light weight (only1/9 ~115 of the glass bottle), convenient to carry and use, low energy consumption in production, airtight, nonvolatile, acid and alkali resistant, and is a good packaging material for carbonated drinks. In recent years, it has become an important filling container for carbonated drinks, tea, fruit juice, packaged drinking water, wine and soy sauce. In addition, Bote bottles have been widely used in packaging bottles of detergents, shampoos, edible oils, condiments, sweets, medicines, cosmetics and alcoholic beverages.
"02"-HDPE (high density polyethylene)
Plastic containers for cleaning products and bath products. At present, most plastic bags used in supermarkets and shopping malls are made of this material, which can withstand the high temperature of 1 10℃, indicating that plastic bags for food can be used to hold food. Plastic containers containing cleaning products and bath products can be reused after careful cleaning, but these containers are usually not easy to clean, making the original cleaning products a hotbed of bacteria, and it is best not to recycle them if they are not thoroughly cleaned.
PE is the most widely used plastic in industry and life, which is generally divided into high density polyethylene (HDPE) and low density polyethylene (LDPE). PE has excellent acid and alkali resistance. Compared with LDPE, HDPE has higher melting point, higher hardness and better liquid corrosion resistance. At present, plastic bags and all kinds of translucent or opaque plastic bottles on the market are almost made of PE, such as detergents, shampoos, bath milk, cooking oil and pesticides. And most of them are bottled in HDPE. LDPE is everywhere in modern life, but not because of its container, but because of the plastic bags you can see everywhere. Most plastic bags and plastic films are made of low density polyethylene.
"03"-PVC (polyvinyl chloride)
According to reports, plastic products made of this material are prone to produce toxic and harmful substances from two aspects, one is monomolecular vinyl chloride that is not fully polymerized in the production process, and the other is harmful substances in plasticizers. These two substances are easy to precipitate when they encounter high temperature and oil, and toxic substances are easy to cause cancer after entering the human body with food. At present, containers made of this material are rarely used for packaging food. If it is in use, don't let it get hot.
PVC material was invented quite early and widely used in industrial products. Because PVC also has the advantages of other plastic materials, and its processability and plasticity are excellent, and its price is cheap, it is widely used, but it is mostly used in non-food aspects, such as water pipes, raincoats, schoolbags, building materials, plastic films, plastic boxes and so on. In the use of containers, it is mostly used to hold vegetable oil, detergent, cake boxes and packaged drinking water. Because this substance contains chlorine, it is suspected that VCM monomer is easily released during bottle making, filling, recycling and reprocessing, which may be harmful to human health. In addition, in recent years, the awareness of environmental protection has risen, and manufacturers have gradually switched to other materials to fill products for filling containers.
"04"-LDPE (low density polyethylene)
Plastic wrap and plastic film are both made of this material. Heat resistance is not strong. Generally qualified PE plastic wrap will melt when the temperature exceeds 1 10℃, leaving some plastic preparations that cannot be decomposed by human body. Moreover, food is wrapped and heated with plastic wrap, and the oil in food can easily dissolve the harmful substances in plastic wrap. Therefore, before putting food into the microwave oven, you must first remove the wrapped plastic wrap.
"05"-PP (polypropylene)
The microwave lunch box is made of this material, which is resistant to high temperature 130℃ and has poor transparency. It is the only plastic box that can be put into the microwave oven and reused after careful cleaning. It should be noted that some microwave lunch boxes are made of PP 05, but the lid is PS 06. PS has good transparency, but it is not resistant to high temperature, so it can't be put in the microwave oven with the box. To be on the safe side, open the lid before putting the container in the microwave oven.
PP and PE can be said to be two brothers, but some physical and mechanical properties are better than PE, so bottle makers often use PE to make bottles, and the caps and handles are made of PP with greater hardness and strength. The melting point of PP is as high as 167℃, which is heat-resistant and the product can be steam sterilized. The most common bottles made of PP are soybean milk and rice milk bottles, as well as 100% pure juice, yogurt, juice drinks and dairy products (such as pudding). Larger containers, such as buckets, trash cans, laundry vats, laundry baskets, baskets, etc., are mostly made of PP, and in recent years, they are also widely used to make disposable tableware or disposable cups (containers used by fast food restaurants to hold ice products, such as the popular "Kuaikeli" chain stores in the market). The container made of this material is opaque or translucent, and has the advantages of acid and alkali resistance, chemical resistance, collision resistance and high temperature resistance (about 20℃~ 120℃).
"06"-PS (polystyrene)
This is the material used to make instant noodle boxes in bowls and foamed fast food boxes. Heat-resistant and cold-resistant, but it can't be put into the microwave oven to avoid releasing chemicals when the temperature is too high. Moreover, it cannot be used to hold strong acids (such as orange juice) and strong alkaline substances, because it will decompose polystyrene that is not good for human body. Therefore, you should try to avoid packing hot food in fast food boxes.
PS has low water absorption and good dimensional stability, and can be processed by injection molding, compression molding, extrusion and thermoforming. Generally, it is divided into foamed type and unfoamed type according to whether it has undergone foaming process or not. Unfoamed PS is mainly used in building materials, toys, stationery and so on. Can also be made into containers filled with fermented dairy products (such as Yakult, Fitness, Duoduo and other dairy products or lactic acid products). In recent years, it has also been widely used to make disposable tableware. Foamed PS (commonly known as styrofoam) is foamed by foaming agent 20 times to 100 times in the process, which is used as a buffer material for packaging household appliances or information articles or an ice cream box or fish box with heat insulation effect, and is generally called EPS (foamed styrene); It is also used to make disposable tableware. This kind of polystyrene foam is usually made into a flat plate, called PSP (expanded polystyrene paper), and then molded into various containers. There are also food-grade EPS-shaped styrofoam, such as coffee cups and grass cups.
"07"-PC and other classes
PC is a widely used material, especially for making bottles and space cups. This is controversial because it contains bisphenol A. Experts point out that in theory, as long as bisphenol A is completely converted into plastic structure in the process of manufacturing PC, it means that the product has no bisphenol A at all, let alone released it. However, if a small amount of bisphenol A is not converted into the plastic structure of PC, it may be released into food or drink. Therefore, special attention should be paid when using this plastic container.
The higher the temperature, the more bisphenol A remaining in PC is released and the faster it is. So PC water bottles should not be used to hold hot water. If your kettle number is 07, the following methods can reduce the risk: don't heat it when using it, and don't direct it in the sun. No dishwasher or bowl dryer is needed to clean the kettle. Before the first use, wash it with baking soda powder and warm water, and dry it naturally at room temperature. If the container is injured or damaged, it is recommended to stop using it, because it is easy to hide bacteria if there are tiny pits on the surface of plastic products. Avoid reusing aging plastic appliances.