Plastics are widely used in all walks of life, especially packaging. Because of the inability or difficulty of self-decomposition, waste plastics not only affect health, but also cause harm to the natural ecology.
At present, recycling is an important way for countries to solve environmental problems caused by plastic waste. Plastic waste that is easy to recycle and has material recovery value should be recycled as much as possible. However, disposable plastic wastes that are difficult to recycle or have no recycling value should be degraded.
Degradable plastics as high-tech products and environmentally-friendly products have become the focus of research and development in the world today, and among them, biodegradable plastics can maintain the characteristics of plastics, namely, stability in use, various applications, ease of handling, and economy. There is a broad prospect in the field of plastic materials.
According to the forecast of related departments, by 2005, China will need 5 million tons of plastic packaging materials, and plastic packaging waste will reach 1.5 million tons; China's area of ​​covering film is 500 million acres, with nursery ladders, agricultural and sideline products preservation Expected demand for materials, etc. will reach 1 million tons, and part of the disposable sundry goods and medical materials are also difficult to collect or not suitable for recycling. It is expected that the demand will reach 1 million tons.
As a result, plastic waste that is difficult to recycle will reach 3.5 million tons, which will lead to increasingly serious environmental problems. If 50% of them are replaced by biodegradable plastics, the demand for biodegradable plastics will reach 1.75 million tons, so the degradable plastics have a large market potential in China. In recent years, domestic packaging plastics have exceeded 4 million tons, among which disposable plastic packaging that is difficult to recycle accounts for about 30%. The annual amount of plastic packaging waste is 1.2 million tons, and plastic plastic film is more than 400,000 tons. Because the plastic film is thin, it is difficult to recycle the plastic film after being broken into the farmland and mixed with a large amount of sand. It is difficult to recycle disposable plastic disposables and medical supplies that are not suitable for recycling, and about 400,000 tons.
In response to disposable lunch boxes and plastic packaging, in 1996 the relevant national departments promulgated the "Law of the People's Republic of China on the Treatment of Solid Wastes", which clearly stipulates that disposable plastic products should be packaged, and should be easily recycled, easy to dispose or easily eliminated in the environment. Nano products. So far, more than 20 provinces and cities across the country have issued banned or restricted ordinary polystyrene plastic foam tableware and ordinary polyethylene packaging bags below 25 microns; in 1998, the State Environmental Protection Administration, the Ministry of Construction, the Ministry of Railways Co-published "Some Provisions Opinions on Strengthening the Management of Waste Plastic Packaging Waste in Key Traffic Routes, Watersheds and Scenic Spots", the main content of which is that EPS cutlery is not allowed on traffic trunks; Emergency notifications for disposable foam plastic tableware, and major cities such as Beijing, Shanghai and Guangzhou introduced the principle of “source control, recycling, step-by-step prohibition, and encourage substitution†after enacting ordinances prohibiting or restricting EPS cutlery and ultra-thin plastic bags. .
The prospect of degradable plastics as high-tech products and environmental protection products is optimistic. Its development not only broadens the function of plastics, but also alleviates the environmental problems to a certain extent. Therefore, all countries are strengthening the research and development of degradable plastics and accelerating their use. Process.