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Resources and environment are major issues facing human beings in achieving sustainable development in the 21st century, and biotechnology will become one of the key technologies to solve this problem. Among the many factors that cause environmental pollution, the public hazards caused by plastic waste have aroused widespread concern in society.

　　 At present, the countries that mainly produce degradable plastics in the world include the United States, Japan, Germany, Italy, Canada, and Israel. The varieties are photodegradable, photo-biodegradable, collapsible biodegradable, and completely biodegradable.

Biodegradable plastics refer to plastics that can be decomposed by microorganisms in the soil. With the help of bacteria or hydrolytic enzymes, the materials can be decomposed into carbon dioxide, water, honeycomb porous materials and salts. They can be completely decomposed after the action of microorganisms and re-enter. The biosphere is currently a hotspot of research and development in various countries. Therefore, biodegradable plastic generally refers to a new type of plastic that has a certain mechanical strength and can be decomposed completely or partially (microorganisms such as bacteria, mold and algae) in the natural environment without causing environmental pollution. The mechanism of biodegradation is mainly by bacteria or their hydrolase decomposing high molecular weight polymers into small molecular weight fragments, which are then further decomposed by bacteria into carbon dioxide and water.

　　 Regarding the fully biodegradable garbage bags, a variety of products have been developed and produced:

　　One, degradable resins and masterbatches include fully biodegradable resins, photo-biodegradable masterbatches and composite degradable masterbatches.

　　Second, degradable plastic products include compost bags, garbage bags, shopping bags, electronic packaging bags, mulching films, dining utensils, golf studs and foam materials.

　　 Third, ordinary plastic products include shopping bags, garbage bags and office supplies.

　　 my country’s biodegradable plastics are mainly used in agriculture, food packaging, degradable foam nets and disposable fast food boxes.

　　Agricultural plastic film agricultural film belongs to the three pillar products of agricultural production (fertilizer, pesticide, agricultural film). It was originally a state-controlled product, and it has been relatively hot on the market. Since 1979, agricultural film mulching cultivation technology has been vigorously promoted in my country. In 1980, the area covered by agricultural film was only 25,000 mu, and by 1992 it reached 50 million mu. The application fields of agricultural film have grown from cotton and vegetables to economic crops, such as peanuts, fruits, sugar beets, sugar cane, tobacco, fruits and food crops such as rice, early rice, wheat, and corn. The promotion and popularization of agricultural film has achieved obvious economic benefits. According to statistics, the increase in output brought by agricultural film from 1982 to 1987 was 7.1 billion yuan; from 1978 to 1989, the cumulative production of plastic film mulching technology increased by 28 billion kilograms of grain and economy. The growth of crops can be seen from the above statistics, the promotion and application of agricultural film bring very significant economic benefits.

　　 In short, the most prominent advantage of degradable plastics is that they are degradable and do not pollute the environment. It is an inevitable development trend to replace polyethylene and other plastics, and the upgrading of plastic film products is also imperative. According to forecasts, the current market size is 30 billion yuan, and it is growing at a rate of 30%-50% every year.