Application Problems of Green Packaging Materials and Corresponding Measures (2)

2. Polylactic acid packaging material

Polylactic acid has become a research and development hotspot worldwide. It is a new type of biodegradable polymer material polymerized by many lactic acid molecules and can be completely decomposed into water and carbon dioxide without any harm to the environment.

In November 2004, the degradable polylactic acid material developed by Shanghai Xinli Industrial Microbial Technology Co., Ltd. and the School of Materials Science and Engineering of Tongji University has been successfully developed and has been listed as a major industrialization project in Shanghai City for Science and Education.

Countries such as the United States, France, and Japan have developed and produced lactic acid from raw materials such as corn, sugar cane, sugar beets, potatoes, and other agricultural and sideline products to produce polylactic acid. The process used by US LLC to make biodegradable plastics from corn is as follows: First, the corn is ground into powder, the starch is separated, and the original glucose is extracted from the starch. Then anaerobic fermentation of Lactobacillus, the fermentation process with liquid caustic soda to generate lactic acid, fermentation broth after purification, using electrodialysis process, made up to 99.5% purity of L-lactic acid. The extracted lactic acid is then made into the final polymer-polylactic acid. The annual global output of 600 million tons of corn makes it the raw material of choice for biodegradable plastics.

The United States CollegeFarm brand candy packaging uses a biodegradable resin polylactic acid film. This film has crystal transparency and excellent kink retention, printability and strength, and is highly barrier to better preserve the aroma of the candy. A German company successfully developed a green food cup with rapid natural decomposition using polylactic acid as a raw material, which has opened up a practical new way to solve the problem of degradation of disposable plastic packaging.

3 natural biological packaging materials

Natural biological packaging materials such as wood, bamboo materials, sawdust, hemp cotton, wicker, reeds, straw, wheat straw, etc., can be easily decomposed in the natural environment, do not pollute the ecological environment, and the resources are renewable and the cost is low. If the bamboo packaging products can be used for the second time, the waste can be burned and utilized; the compost can be used as fertilizer; the waste can be naturally degraded. Bamboo-engraved plywood is an excellent green packaging material because of its high strength, low price, light weight, easy recycling of waste, and no environmental pollution.

4. Food waste green packaging

According to the New Scientist magazine, biochemists at the Hawaii Institute of Natural Energy have made food waste a biodegradable polymer that researchers have humorously called "perfect plastic." This type of plastic, which can be degraded in a short time, is widely used not only for making packages such as bottles and bags but also for making capsules for medicines. According to the biochemist of the Institute of Natural Energy, the raw material of the new biodegradable plastic is a mixture of water and various food wastes, and 22 to 25 kg of biodegradable plastic can be produced per 100 kg of mixture, which greatly reduces the production cost.

Measure

1. Formulate a green packaging material development plan

The development of green packaging materials involves many high-tech, industrial developed countries have been researching fully biodegradable plastics for several years, but so far there are not many real industrial products, which involves many experimental research and industrial production problems. The development of green packaging materials is not only a matter of the packaging industry, but also requires the cooperation of the entire industry; not only industrial enterprises, but also research institutes and universities. Therefore, it is necessary to formulate a five to ten year development plan for green packaging materials, and put forward major research and development projects and objectives, such as high-performance, low-cost pulp molded disposable tableware and packaging products, and honeycomb box instead of wooden box packaging. Production equipment, plant fiber cushioning packaging products, fully biodegradable plastics, edible packaging materials, high-strength thin-walled lightweight glass bottles, high-quality recycling and recycling technologies for waste packaging, especially high-quality recycling technology for waste plastics, waste The green plastic technology of the company concentrates on people's property, organizes elite teams, and has plans and targets to carry out research on collaborations, so that the development of our country's green packaging materials will enter the world's forefront.

2. Formulate and improve the legal system of green packaging

The regulatory content of green packaging materials should include environmental standards for green packaging materials, administrative regulations to control the total amount of emissions, as well as technical regulations for the prevention and elimination of environmental pollutants discharged into the environment, and also the use of used packaging waste. A system for recycling and reuse, and set 5, 10 years to achieve the goal of recycling of packaging materials. Green packaging materials regulations can also be incorporated into green packaging regulations, such as the "Packaging Waste Restriction Act" or "Packaging Law."

In the past decade or so, developed countries have taken measures one after another and have formulated various laws and directives. There are mainly the following types: First, it is stipulated in the form of legislation to prohibit the use of certain packaging materials. For example, legislation prohibits the use of packaging materials that contain lead, mercury, and copper as components; appliances that cannot be reused; packaging materials that do not achieve a specific recycling ratio. The second is to establish a storage return system. Many countries require that alcoholic beverages and soft drinks should use reusable containers. Some countries (such as Denmark) require that they fail to meet this standard and refuse to import it. The third is the implementation of tax incentives or fines. That is, manufacturers who manufacture and use packaging materials are given tax exemption, low tax concessions, or higher taxes based on the safety of the raw materials or packaging used in the packaging they produce, or the use of partially recycled packaging materials. Encourage the use of renewable resources. The fourth is to promote proper packaging. Excessive packaging causes waste of resources and also causes unnecessary environmental pollution. Some developed countries are advocating proper packaging and have introduced some regulations in succession. For example, in the United States, the degree of complexity of product packaging has been regulated to a certain extent according to a certain proportion. If excessive packaging exceeds the requirements, then heavy penalties will be imposed. This will force manufacturers to simplify packaging. Japan even proposes zero packaging.

Although China does not have a green packaging law, it does not mean that there are no laws and regulations that regulate green packaging. As the environmental pollution caused by packaging is a part of environmental issues, green packaging is an important aspect of protecting natural resources and preventing environmental pollution. Therefore, it should be regulated by the Environmental Protection Law. The "Environmental Protection Law" defines the principle of harmonization of environmental protection with economic and social development; the principle of prevention, prevention and control, and comprehensive management; polluter pays, user compensation, developer protection, principles of saboteur recovery, and reliance on The principle of the masses to protect the environment. In addition, the "Environmental Protection Law" also stipulates the basic systems of the environmental impact assessment system, the "three simultaneous" system, the pollutant discharge system, the permit system, and the deadline governance system. Legislation management, as a compulsory measure in environmental management, is an effective measure adopted by all countries in the world. To protect the smooth operation of the green packaging system, a sound and complete legal system must be established, and the production of packaging must be managed through legislation. Circulation and use, with laws and regulations to promote the development of green packaging.

3, research and development of environmental protection production and recycling technology

The environmental performance of packaging materials should be evaluated throughout the life cycle. In fact, the environmental pollution caused by paper, plastics, metal, and glass packaging used mainly in the production process is far greater than the environmental pollution caused by waste disposal. For example, waste paper discharged from paper packaging in pulp and paper, and plastic packaging in petroleum raw materials. Pollution caused by atmospheric pollution in the refining process, noise caused by metal edging, coating process, and body and mind pollution caused by smoke and dust, and dust and carbon dioxide and Z-silicon dioxide emitted by glass packaging during the smelting process. The pollution brought about is very serious. Therefore, in order to make the packaging material have "green" performance throughout its life cycle, clean production must be carried out. Among the three elements of "clean energy and raw materials," "clean production processes," and "clean products," the most important is the development of clean production technology. Clean production processes are "less waste" and "non-waste" processes. It is necessary to establish the production of closed loops to volatilize or precipitate or run off the material lost in the production process through recycling; as a raw material and then reuse, establish a closed production process from raw material input to waste recycling, try to Reducing the amount of wastes discharged from the outside world will not only increase the utilization rate of resources, but also radically eliminate the “three wastes” and prevent the packaging industry from causing harm to the environment. China has formally implemented the "Cleaner Production Promotion Law" from January 1, 2003. Enterprises that are toxic and harmful to the production process and pollute the environment must be subject to compulsory cleaner production audits. Therefore, it is very important for the development of green packaging materials to vigorously develop clean production process technologies for green packaging materials.

Packaging made from a single material is easy to recycle, and multi-layered composites must be considered for ease of separation without hindering reuse. If the aluminum beverage is coated with an organic coating on the surface, the organic coating can be burned without causing difficulties in recycling, and the composite paper-plastic packaging is difficult to separate for purification. However, composite materials are widely used in packaging materials, such as plastic composites, paper-plastic composites, plastic-aluminum composites, paper-plastic aluminum composites, plastic-wood composites, and other composite methods. Their greatest advantage in use is that they have multiple functions. , Such as a variety of barrier functions, moisture permeability, etc., to make it high-performance. The economic benefits are very prominent. The biggest disadvantage of composite materials is that they are difficult to recycle, difficult to separate and separate, and composite materials such as mixed into a single material will cause the recovery quality of a single material to be damaged. For example, aluminum paper and plastic composite materials are mixed into a single cardboard recycling material. , it will destroy the beating performance; composite film such as mixing into a single plastic film, will also make recycled recycled products scrapped. Therefore, when the composite material is recycled, it can only be used as a fuel, and it is burned in the incinerator to recover heat energy. The current solution to the contradiction between high functionality and environmental performance of composite materials. The main directions are: 1 to develop a single high-performance material to replace composite materials; 2 to develop green composite materials that are easy to recycle. Both are difficult to develop.

Luo Guanglin Yang Xinfang

Source: "China Packaging Industry"