Plastics are mainly divided into the following seven categories according to their materials
1. Polyethylene terephthalate (PET)
General mineral water, carbonated drinks and functional beverage bottles are made of this material and can be recycled. Heat resistant to 70 ℃, can not be filled with hot water, in the use of more than 10 months, will release DEHP carcinogen, it is recommended to throw away the drinking water bottle. It is the most widely used beverage packaging nowadays. Tens of billions of PET plastic bottles are produced in China every year. It is estimated that more than 500000 tons of pet will be used in the manufacture of PET plastic bottles by 2005.
2. High density polyethylene (HDPE)
Plastic containers for cleaning products or plastic bags commonly used in shopping malls are made of this material. It can withstand high temperature of 110 ℃. If it is indicated for food, it can be used to hold food. It can be reused after careful cleaning, but it often leaves residues and becomes a hotbed of bacteria, which can be recycled.
3. Polyvinyl chloride (PVC)
Common in raincoat, plastic film. The plastic products made of this material are easy to produce two kinds of toxic and harmful substances. They are easy to separate out when meeting high temperature and grease, and are easy to cause cancer. Therefore, they are rarely used in food packaging. Do not put plastic bottles containing edible oil at high temperature. They are not suitable for recycling.
4.Low density polyethylene (LDPE)
The raw materials of fresh-keeping film and plastic film are not heat-resistant. When the temperature of qualified PE film exceeds 110 ℃, it will melt. When heating food in microwave oven, don't forget to take off the plastic film, otherwise it will leave some plastic preparation which can't be decomposed by human body. The recycling value of this kind of plastic is not high.
5.Polypropylene (PP)
This material can be heated in the microwave oven. It can withstand high temperature of 130 ℃, melting point of 167 ℃, poor transparency, and can be reused after cleaning. It can be recycled, but because of the cumbersome processing process, there are not many recycling plants to do so. But individuals can safely reuse the plastic. Although some take out boxes are PP, if the cover is transparent, it may be made of PS. remember to remove the cover when heating in the microwave oven.
6. Polystyrene (PS)
This is the material used to make the bowl filled instant noodle box and foam fast food box. Can not be used to contain strong acids (such as orange juice), strong alkaline substances, because it will decompose polystyrene (carcinogen). It is not allowed to heat the instant noodle box directly in the microwave oven. It's hard to recycle.
7. Other plastics include acrylic acid, polycarbonate, etc
It is a kind of material which is widely used in the manufacture of milk bottles, space cups and so on. The following methods can be used to avoid toxic bisphenol A: do not heat when using, do not directly in the sun; do not use dishwasher or dishwasher; before the first use, clean with baking soda powder and warm water, and dry naturally at room temperature; if the container is damaged or damaged, stop using immediately to avoid repeated use of aged plastic utensils.
The plastic classification number only indicates the difficulty or frequency of recycling the material. Although most plastics can be recycled, they need to be classified according to the type of polymer they are. Moreover, due to the cost of selection, classification, cleaning and reprocessing, some materials, such as PP, can be purchased directly at a lower price than recycled materials. At present, they can only cope with the recovery of polyethylene terephthalate (PET) and high-density polyethylene (HDPE).
The resource consumption and environmental hazards caused by plastics have attracted extensive attention. Various countries are also exploring the recycling and alternative products of plastic products. The EU, Japan, South Korea and other Northeast Asian markets have provided strong regulatory support for plastic recycling. Some Asian countries (such as Singapore, Malaysia and Thailand) are promoting plastics recycling by strengthening supervision through new laws and National Plastics plans. China fosters a recycling culture through compulsory household waste sorting. Several markets, such as Singapore, Malaysia, Hong Kong, China and Thailand, also provide financial support programs and tax incentives for companies that reduce plastic waste and implement plastic recycling. Some financial institutions, such as UOB, can provide plastic recycling ecosystem financing solutions for plastic recycling, conversion and integration collectors.
Plastics have brought convenience to our lives and made due contributions to the development of science and technology and other fields. However, due to the large amount of discarded waste plastics, they are not easy to degrade, difficult to treat, have a wide range of impacts and serious pollution. Before the invention of new substitutes, the use of plastics has always been the mainstream of our life, so what we can do now is to recycle them reasonably Plastic products at the same time to minimize the use of plastic products.
