Analysis of the future development prospect of the

Analysis of the future development prospects of degradable plastics (Part 2)

on the other hand, the increasingly stringent environmental protection regulations in various countries have also promoted the application of biodegradable materials. For example, Europe has formulated the standard EN13432 on biodegradable composting plastics, which gives biodegradable plastics a unified detection and evaluation method; Germany has enforced the packaging decree since June, 2005. Plastic packaging must be recycled, but biodegradable composting plastic or packaging made of bioplastics may not be recycled during the transition period from May 28, 2005 to December 31, 2012; France stipulates that biodegradable disposable retail handbags will be used from 2010; The Japanese government also set a goal that by 2020, 20% of all plastic bags consumed in Japan will come from renewable resources

the research and development of biodegradable materials in China has always been synchronized with that in the world. Since 2001, the biodegradable materials working group of the National Center for standardization of plastic products has begun to draft and formulate standards related to biodegradable materials, such as testing methods, definitions and performance requirements of degradable plastics, and degradable plastic sheet products. These standards are formulated with reference to international standards. Up to now, China and major international bioplastics organizations have established a cooperative relationship of detection and identification mutual recognition

in this year's Beijing Olympic Games, 5.7 million garbage bags were all biodegradable plastic bags. This kind of plastic bag can be decomposed into carbon dioxide and water within 72 days after being discarded

in recent years, relevant scientific and technological personnel in China have been committed to the R & D and application of bioplastics. The bio based Corps composed of biodegradable material production and R & D enterprises has become a strong global Corps. For example, the plastic starch biodegradable (PSM) material developed by Wuhan Huali Environmental Protection Technology Co., Ltd. takes plant starch, cellulose, bamboo powder, chitosan, etc. as the main raw materials. Through the modification and plasticization of starch and other materials, it integrates rigidity, toughness and elasticity. It is reported that PSM is the only biodegradable material in China that has passed the EU EN13432 standard testing and certification, and its degradation performance, service performance and health indicators are at the international leading level

like plants storing sugar with starch, many microorganisms in nature use a polyester called PHA to store energy. Taking advantage of the good biocompatibility of PHA, Ningbo Tian'an biomaterials Co., Ltd. not only won a place in the international market, but also became the largest manufacturer of PHA raw materials in the world; With an annual production capacity of 5000 tons of PLA, Zhejiang Haizheng biomaterials Co., Ltd. ranks second in the world in terms of industrial production of polylactic acid

under the banner of circular economy, carbon dioxide copolymers, which are obtained by catalytic synthesis using carbon dioxide waste gas generated in industrial production, are another kind of biodegradable materials. Inner Mongolia Mengxi Group Co., Ltd. cooperates with the Changchun Institute of Applied Chemistry of the Chinese Academy of Sciences to produce carbon dioxide based fully degradable plastics using the carbon dioxide produced in the process of cement production, and has built the world's first continuous and fully enclosed pilot production line with an annual output of 3000 tons of carbon dioxide based fully degradable plastics. The plastics produced are transparent and biodegradable, and the incineration process only produces carbon dioxide and water

degradable plastic refers to a kind of plastic whose properties can meet the use requirements and remain unchanged during the storage period, but can degrade into environmentally friendly substances under natural environmental conditions after use, so as to ensure the accuracy of impact test and prolong the service life of equipment. Therefore, it is also called environmentally degradable plastic

polymer degradation refers to the process of macromolecular chain breaking caused by chemical and physical factors, which is coordinated by energy strategy. The degradation process of macromolecular chain breakage of polymers exposed to oxygen, water, radiation, chemicals, pollutants, mechanical forces, insects and other animals, microorganisms and other environmental conditions is called environmental degradation. Degradation reduces the molecular weight of polymer and the physical properties of polymer materials until polymer materials lose their usability. This phenomenon is also known as aging degradation of polymer materials

the degradation process of environmental degradable plastics mainly involves biodegradation, photodegradation and chemical degradation, which are the three main types. 6. Gb/t 10808 ⑵ 006 determination of tear strength of polymer porous elastic materials. The degradation process has synergistic, synergistic and coherent effects with each other. For example, photodegradation and oxide degradation often occur simultaneously and promote each other; Biodegradation is more likely to occur after photodegradation

the aging degradation of polymer is directly related to the stability of polymer. The aging degradation of polymers shortens the service life of plastics. For this reason, since the advent of plastics and the active support of the Beijing municipal government, scientists have been committed to the research on the anti-aging of such materials, that is, the stabilization, in order to produce high stability polymer materials. At present, scientists from all countries are also competing to develop environmentally degradable plastics by using the aging and degradation behavior of polymers

the main application fields of degradable plastics include agricultural plastic film, various plastic packaging bags, garbage bags, shopping bags in shopping malls, disposable tableware, etc

corn plastic is only one kind of degradable plastics. It is a fully degradable biological environmental protection material, which can completely replace the non degradable traditional chemical plastics such as polystyrene, polyethylene, polyester, etc. it is regarded as the fourth kind of new materials after metal materials, inorganic materials and polymer materials. Corn plastic can be made into building wall panels, packaging materials, textile fabrics, household appliances, agricultural mulch, carpets, daily plastic bags and medical materials according to different needs. Therefore, the development of corn plastics has broad market prospects. More importantly, these items made of corn plastic can be composted and landfilled after being discarded. Under the action of natural microorganisms, they will be completely decomposed into water and carbon dioxide, which not only does not pollute the environment, but also can be applied to farmland as organic fertilizer to become plant nutrients

there is a common problem in the current degradable plastics, whether corn plastics, starch plastics or other biodegradable plastics, that is, the manufacturing cost is too high to be popularized or widely used like the existing polystyrene, polyethylene, polyester, etc. in addition to international events such as the Olympic Games, it is difficult to be widely used in people's daily life. The author believes that the biggest obstacle is the high price. This price is based on the production technology and cost. Therefore, it is indispensable to improve the technical level and reduce the cost of raw materials if we want to have a more far-reaching development and wider application of degradable plastics