Several grades of plastic bottles


The bottom of the plastic bottle has the secret number […]

The bottom of the plastic bottle has the secret number 0-7. The implied toxicity level. The Society of Plastics Industry (SPI) has developed the symbol bai code of the type of plastic used in plastic products, which is represented by a cycle composed of three arrows. In the middle of the triangle, a number sign is added. They attach the triangle recycling mark to the plastic product and use numbers 1 to 7 and English abbreviations to refer to the type of resin used in the plastic. In this way, the identification of plastic varieties becomes simple and easy, and recycling costs are greatly reduced. Many countries in the world have adopted this set of SPI marking schemes. China formulated almost the same labeling standards in 1996.

The first goal of plastic packaging waste treatment is to recycle containers, etc., as resources, so as to protect limited resources and complete the recycling of packaging containers. Among them, 28% of PET (polyethylene terephthalate) bottles for carbonated beverages can be recycled, and PE-HD (high-density polyethylene) (high-density polyethylene) for milk bottles and PE-HD for soda bottles can also be effectively recycled.
In order to facilitate the recycling of various post-consumer plastic products, various plastics need to be sorted. Due to the many and complicated plastic consumption channels, some post-consumer plastics are difficult to distinguish simply by appearance. Therefore, it is best It can indicate the material variety on the plastic products. What are the uses, advantages and disadvantages of different codes? The following content will help you understand these:

Plastic name--------code and corresponding abbreviation code are as follows:

Polyester ——— 01—PET (Pote Bottle) such as: mineral water bottle, carbonated beverage bottle

Do not recycle beverage bottles for hot water
Use: It is heat-resistant to 70℃, only suitable for warm or frozen drinks. It is easy to deform when it is filled with high-temperature liquid or heated, and substances harmful to the human body will melt. In addition, scientists discovered that after 10 months of use for No. 1 plastic, it may release the carcinogen DEHP, which is toxic to the testis.
Therefore, throw away the beverage bottle when it is used up, and don't use it as a water cup, or as a storage container to carry other items, so as not to cause health problems.

High-density polyethylene-02-HDPE such as: cleaning products, bath products

It is recommended not to recycle if cleaning is not thorough
Use: It can be reused after careful cleaning, but these containers are usually not easy to clean. The original cleaning supplies remain and become a hotbed of bacteria. You'd better not recycle them.

Polyvinyl Chloride———— 03—PVC Such as: some decorative materials

Use: This material is prone to produce harmful substances when it is high temperature, and it will even be released during the manufacturing process. After the toxic substances enter the human body with food, it may cause breast cancer, birth defects and other diseases. At present, containers of this material are less used for packaging food. If it is in use, do not let it heat up.

Low density polyethylene——04—LDPE such as: cling film, plastic film, etc.

Do not wrap the food in the microwave oven
Use: The heat resistance is not strong. Generally, qualified PE cling film will melt when the temperature exceeds 110°C, leaving some plastic preparations that cannot be decomposed by the human body. In addition, when food is wrapped with plastic wrap and heated, the fat in the food can easily dissolve harmful substances in the plastic wrap. Therefore, when food is put into the microwave oven, the wrapped plastic wrap must be removed first.

Polypropylene—————— 05—PP (Can withstand temperatures above 100 degrees) Such as: microwave oven lunch box

When putting it in the microwave, remove the lid
Use: The only plastic box that can be put in a microwave oven, can be reused after careful cleaning. Special attention should be paid to some microwave lunch boxes. The box body is indeed made of No. 5 PP, but the lid is made of No. 1 PE. Because PE cannot withstand high temperatures, it cannot be placed in the microwave together with the box. To be safe, remove the lid before placing the container in the microwave.

Polystyrene———— 06—PS (heat resistance 60-70 degrees, hot beverages will produce toxins, and styrene will be released when burned) such as: bowls of instant noodle boxes, fast food boxes

Don't use the microwave to cook instant noodles
Use: It is heat-resistant and cold-resistant, but cannot be placed in a microwave oven to avoid the release of chemicals due to high temperature. And it cannot be used to carry strong acids (such as orange juice) and strong alkaline substances, because it will decompose polystyrene, which is not good for the human body, and is easy to cause cancer. Therefore, you should try to avoid using fast food boxes to pack hot food.

Other plastic codes-07—Others such as: water bottle, water cup, milk bottle

PC glue meets heat to release bisphenol A
Use: A material that is used in large quantities, especially in milk bottles, and is controversial because it contains BPA. Lin Hanhua, an associate professor in the Department of Biology and Chemistry of the City University of Hong Kong, said that in theory, as long as 100% of BPA is converted into a plastic structure during the production of PC, it means that the product is completely free of BPA, let alone released. 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, be careful, and pay special attention when using this plastic container.

Cleaning measures to deal with bisphenol A:
The residual bisphenol A in PC, the higher the temperature, the more release and the faster the speed. Therefore, the PC water bottle should not be used to hold hot water, so as not to increase the release rate and concentration of bisphenol A (if any). If your kettle has a number 7, the following methods can reduce the risk:
●Do not heat during use.
●Do not use dishwasher or dish dryer to clean the kettle.
●Do not expose the kettle to direct sunlight.
●Before using for the first time, wash with baking soda powder and warm water and dry naturally at room temperature. Because bisphenol A will release more in the first use and long-term use.
●If the container has any fall or damage, it is recommended to stop using it, because if the surface of the plastic product has fine pits, it is easy to hide bacteria.
● Avoid repeated use of aging plastic appliances.

Among them, PP, PE, PVC are the abbreviations of English names. The Chinese names are polypropylene, polyethylene, and polyvinyl chloride. The full English names are polypropylene, polyethylene, and polyvinyl chloride.

Some of our common old-fashioned slippers are made of PVC. They become very hard in summer and winter, which has a lot to do with the temperature sensitivity of PVC. PVC will decompose toxic gas-chlorine at high temperature. Among the three, PVC has the highest density.

Ordinary plastic bags are made of PE, which has better toughness. PE is also divided into HDPE (high-density polyethylene) and LDPE (low-density polyethylene). The difference in density results in some of its properties. difference.

PP is a relatively safe plastic among plastics. General food packaging bags are made of it. Of course, PP also has grades. Food grade packaging must be used. PP has the smallest density among the three and can float on water.

Generally, these polymer materials can be modified by adding some other materials to make them superior in overall performance or in a certain aspect for special purposes. Of course, the price will increase greatly after modification.

The following methods can be used to detect toxic and non-toxic plastic bags:

Sensory testing method: non-toxic plastic bags are milky white, translucent, or colorless and transparent, flexible, smooth to the touch, and waxy on the surface; toxic plastic bags are cloudy or light yellow in color and sticky to the touch.

Water testing method: Put the plastic bag in the water and press it into the bottom of the water. The non-toxic plastic bag has a small specific gravity and can surface. The toxic plastic bag has a large specific gravity and sinks.

Shake detection method: grab one end of the plastic bag with your hand and shake it vigorously. Those with a crisp sound are non-toxic; those with a dull sound are poisonous.

Fire detection method: non-toxic polyethylene plastic bag is flammable, the flame is blue, the upper end is yellow, and it drips like candle tears when it burns, has a paraffin smell, and has less smoke; toxic PVC plastic bags are not flammable and leave the fire When it is extinguished, the flame is yellow, the bottom is green, it can be softened, and it has a pungent smell of hydrochloric acid.

The bottom of the plastic bottle has a secret number implied toxicity level
When using plastic containers, be sure to read the numbers marked in the triangle at the bottom of the bottle. Only when you understand the properties of the material can you use it in a suitable environment.

"The triangle composed of three arrows is usually printed on the bottom of the plastic bottle, and there is a number in it, ranging from 1 to 7. For example, the number "1" is marked with "PET", which is a chemical name It is a substance of'polyethylene terephthalate', which is commonly used in mineral water bottles, carbonated beverage bottles, etc. When PET heats up to 70°C and is easily deformed, substances harmful to the human body will leach out. At the same time, it cannot Keep it in the car and do not put alcohol or oil in it."