The current status of biodegradable plastics in the market

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In recent years, the plastic industry has developed rapidly, with the world’s total plastic production exceeding 170 million tons. Its applications have penetrated all sectors of the national economy as well as various aspects of people’s lives, and it ranks alongside steel, wood, and cement as one of the four key structural materials. However, the drawback of plastic is that it is difficult to degrade in the natural environment or landfills after use, thus becoming waste that pollutes the environment. Data shows that the mass fraction of plastics in urban solid waste has reached over 10%, while the volume fraction is around 30%. Developing biodegradable plastics can reduce white pollution and bring significant economic and social benefits. At present, the research and development of biodegradable plastics are very active, and some have entered industrial production. Overall, current biodegradable plastics still require further in-depth research on their technologies, improvements in performance, cost reduction, expansion of applications, and gradual introduction to the market. Currently, the main countries that produce biodegradable plastics are the United States, Italy, Germany, Canada, Japan, China, and others. The United States is one of the main countries involved in the development of biodegradable plastics. There are over a dozen organizations in this field, such as the Plastic Degradation Research Consortium (PDRC) and the Bio/Environmental Degradable Plastics Research Society (BEOPS). Their goal is to carry out research on the synthesis of such materials, their processing techniques, degradation tests, as well as the establishment of testing technologies and standard systems. In recent years, Japan has successively established a research committee on biodegradable plastics and a review committee for the practical application of such plastics. The Japanese Ministry of International Trade and Industry has classified biodegradable plastics as a \"fourth type of new material\", following metal materials, inorganic materials, and polymer materials. Europe’s Bhre-Eurae has even established a comprehensive degradation assessment system for biodegradable plastics. In recent years, research and development on fully biodegradable plastics have been most active in developed **. It is reported that in 1998, the global annual production of fully biodegradable plastics was around 30,000 tons; by 2001, production in the United States, Western Europe, Japan, and other regions had increased to about 70,000 tons. Currently, the degradable products available abroad are mainly fully biodegradable plastics, and this will remain the direction for industrial development in the medium to long term. Plastics that can be degraded are mainly classified into photodegradable plastics, biodegradable plastics, and photo-biodegradable plastics based on their degradation mechanisms. The photodegradation technologies already used abroad are of two types: synthetic and additive. The former involves introducing photosensitive groups into the main chain of the olefin polymer, while the latter involves adding photosensitive chemical additives to the polymer. At present, the most research has been conducted on ethylene copolymer-based photodegradable polymers. Studies have shown that when polyethylene degrades into oligomers with a molecular weight of less than 500, it can be absorbed and degraded by microorganisms in the soil, resulting in good environmental safety. Companies such as DuPont and Dow Chemical in the United States, Bayer in Germany, as well as the University of Toronto in Canada have all utilized this technology to achieve industrial production. Biodegradable plastics refer to polymer materials that can be rapidly degraded in natural environments through the metabolic activities of microorganisms. Based on their degradation properties, they can be divided into fully biodegradable plastics and bio-degradable plastics. Based on their origin, they can be classified into natural polymer materials, microbially synthesized materials, chemically synthesized materials, and blended materials. Natural polymer-based biodegradable materials are those made from natural polymer substances such as starch, cellulose, chitin, and proteins. Such substances are abundant in source, fully biodegradable, and their products are safe and non-toxic, which has led to an increasing focus on them. The American company Warner-Lambert has developed a new type of resin made up of 70% amylopectin and 30% amylose, which possesses good biodegradability and can replace various biodegradable materials used in agriculture. Japan uses a combination of cellulose derivatives and deacetylated polysaccharides to produce films via the cast process; these films have strength comparable to that of polyethylene films, and they can be completely degraded within about two months. Although natural polymer materials are fully biodegradable, their poor thermal and mechanical properties prevent them from meeting the requirements of engineering materials. Therefore, current research focuses on modifying natural polymers to produce biodegradable plastics with practical utility.