Plastics are macromolecular compounds (macromolecules) polymerized by addition polymerization or polycondensation with monomers as raw materials. They have moderate deformation resistance, intermediate between fibers and rubber, and are composed of synthetic resins, fillers, plasticizers, and stabilizers. Additives, lubricants, colorants and other additives.
[sù liào] Come on!
Plastic is
"The rapid biodegradation of plastic in the intestinal tract of Tenebrio molitor has revealed a new fate of plastic waste discarded in the environment," said Professor Yang Jun of Beijing University of Aeronautics and Astronautics.
Plastic is difficult to degrade naturally in the environment, and polystyrene is the most. Due to its high molecular weight and high stability, it is generally believed that microorganisms cannot degrade polystyrene plastics. In 2015, the research group of Professor Yang Jun of Beijing University of Aeronautics and Astronautics, Dr. Zhao Yan of Shenzhen Huada Gene Co., Ltd. jointly published two sister research papers in the authoritative journal Environmental Science & Technology in the field of environmental science, which proved that
The development of plastic technology is changing rapidly. The development of new materials for new applications, the performance improvement of existing material markets, and the improvement of performance for special applications can be described as several important directions for new material development and application innovation.
New high thermal conductivity bioplastic
Plastic varieties
Softening or melting range / ° c
Plastic varieties
Softening or melting range / ° c
Polyvinyl acetate
35 ~ 85
Polyoxymethylene
165 ~ 185
Polystyrene
70 ~ 115
Polypropylene
160 ~ 170
PVC
75 ~ 90
Nylon 12
170 ~ 180
Polyethylene (density 0.92g / cm ^ 3)
110
Nylon 11
180 ~ 190
Polyethylene (density 0.94g / cm ^ 3)
About 120
Before various plastic recycling methods are used to recycle waste plastic, most of them need to be sorted. Because plastic consumption channels are numerous and complicated, and some post-consumer plastics are difficult to distinguish by appearance, it is best to indicate the type of material on the plastic product. China has formulated GB / T162882008 "Plastic Packaging Products" with reference to the material variety mark proposed and implemented by the American Plastics Association (SPE).
Health hazards of plastics
Plastic packaging materials have the advantages of light weight, high strength, good impact resistance, transparency, moisture resistance, aesthetics, stable chemical properties, good toughness and corrosion resistance. They have widely replaced metal, wood, paper, glass, leather, etc. in the packaging field. Therefore, plastic packaging has played an irreplaceable role in reducing China's pressure on resources and energy. However, plastic packaging materials have a fatal weakness, that is, their natural degradation time is long, some as long as more than 100 years. The non-degradable nature of plastics results in long-lasting waste. Moreover, it is often discarded once consumed, so plastic packaging waste has become an increasingly prominent environmental problem, forming the so-called "white pollution", which has put a lot of pressure on the human living environment. Recycling is imminent.
Plastic Health Tips
Plastic cups are safer than paper cups
The plastic product code 5 can withstand temperatures up to 130 degrees, which can be filled with hot water and heated by microwave
The darker the straw, the less safe it is
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Do not use plastic straws for hot drinks
Reduce the use of plastic bowls and melamine bowls
Don't use dark colored plastic bowls
Melamine tableware cannot hold acid
Mineral water bottle and pure bucket code "1"
Plastic bottles can store dry items
Water bottle code 5 is resistant to high temperatures and can be reused
Qualified plastic lunch boxes are marked with "5" pp, and there is a vent hole on the lid. As plastic will add certain additives, the darker the color of the plastic, the deeper the additives are added, or the more harmful substances remain , Is not safe, and pp stands for polypropylene, which is not suitable for plastic lunch boxes, which is not environmentally friendly.
