The only way for the development of green plastic packaging materials

Over 20 years of development history of plastic packaging materials, the output has reached more than 6 million tons, and it has grown from the original packaging-free, simple packaging to today's fine packaging. With the economic development of the society and the improvement of the material civilization, people’s The packaging concept is changing. Nowadays, more and more people are realizing that establishing environmental awareness and keeping up with the trend of international green packaging is the only way to shorten the gap between China's plastic packaging and the developed countries' industries and meet the demands of the domestic and foreign trade markets.

The greenization of plastic packaging materials includes two aspects: On the one hand, it is necessary to effectively solve the problem of environmental pollution caused by waste plastics in plastic packaging; on the other hand, in light of China's national conditions, it is necessary to attach great importance to the hygiene and safety of food packaging materials. Sex. The main market for plastic packaging materials is food packaging, and current food hygiene and safety have become a topic of concern in the country. At the same time, the safety and hygiene of soft packaging bags and bottles for food and pharmaceutical packaging have also aroused concern. According to the inspection results of the instrument packaging film (bags) announced by the National Quality Inspection Bureau at the end of September last year, the failure rate was as high as 15%. The major quality problems that existed were the inconformity of the hygienic indicators and the poor physical and mechanical properties of the products. Hygiene indicators include evaporation residues (acetic acid, ethanol, n-hexane), consumption of potassium permanganate, heavy metals, and decolorization tests. The composition of food flexible packaging is mainly plastic film or aluminum foil; adhesives and inks, of which plastic film accounts for 70% of the total packaging, adhesives account for 10%, ink accounted for 10%, other accounted for 10%. Currently, solvent-based polyurethane adhesives and toluene inks are commonly used in the domestic market, and there are serious health problems and safety hazards in the applications. First of all, a large amount of harmful substances such as benzene, toluene, etc., which are discharged into the air, cause pollution to the environment and also pose a danger to the health of workers and consumers. Furthermore, organic solvents may remain between the composite membranes and migrate from the membrane to the food over time to deteriorate and taste bad. Second, many companies do not have effective control over the monitoring of solvent residues in the packaging; third, for production The neglect of the transport process can also lead to pollution. Therefore, only when all the links are effectively controlled can companies ensure that the packaging materials produced are safe.

In Europe or the United States, flexible packaging adhesives have gradually shifted to water-based or solvent-free products (Rohm and Haas, USA is the world's largest supplier of water-based adhesives. In the Chinese food and pharmaceutical flexible packaging market, Rohm and Haas has introduced The US market has matured environmental friendly water-based adhesives. The company's water-based adhesive series does not contain TDI and organic solvents, and its performance can fully meet the requirements of films and films, films, and aluminized films used in general snack food packaging. The inter-process dry compounding requirement, which replaces solvent-based polyurethane adhesives, and can be used on solvent-based dry scrubbers; and alcohol-soluble inks replace toluene inks in Europe and the United States; Japan and South Korea become the main trend (Sikiba, Switzerland ( Shanghai) Ink Co., Ltd. manufactures alcohol-soluble inks for pharmaceuticals and food packaging. Its products do not contain toluene and heavy metals, and do not contain migrating small molecule solubilizers.

In terms of laws and regulations, foreign countries have long paid attention to the environmental protection issue of flexible packaging. Many countries and regions have established laws and regulations accordingly, such as the US Food and Drug Administration (FDA); the European Union’s EU, and Germany’s BgVV, which are clearly stipulated for use. Food and pharmaceutical packaging adhesives and ink types, as long as they are chemical crystals not mentioned in the regulations, are strictly prohibited. In developed countries such as Europe and the United States, water-based adhesives and insoluble adhesives account for 50% of the amount of products used, and the use of solvent-based adhesives also requires a recovery solvent device.

At present, China's flexible packaging industry is facing a number of primary products, high proportion of small businesses. From the perspective of long-term development, we need domestic and international famous brands to drive the development of the entire industry, and eliminate backward companies through the market; national government regulatory authorities must strengthen legislation, especially the Food and Drug Administration to establish laws and regulations as soon as possible, and flexible packaging companies must truly Self-discipline; More and more green foods are on the market today, but many green foods lack green packaging. Green packaging should use environmentally friendly packaging materials, printing inks and adhesives. As China's packaging industry grows rapidly, it must pay attention to hygiene and environmental protection, allowing consumers to be assured of the food itself and also have confidence in the health status of food packaging. Accelerating the overall improvement of the quality and hygiene requirements of the soft plastic packaging industry is to meet the new requirements of the soft plastic packaging industry in line with China's integration with international standards.

At present, China's production of water solvents, alcohol solvent adhesives are also rising, the production of benzene-free alcohol ink is also in development, Shanghai Lianyin Company, Zhejiang New Oriental Ink Group, Huangyan Huaguang Resin Company, Beijing Gaomeng Chemical Company All will undertake the drafting of the polyurethane adhesives industry for food composite packaging, which will promote the progress of industry standardization.
The consumption of plastic packaging materials has exceeded 6 million tons, and the environmental pollution and environmental protection of waste is particularly significant. The recycling of waste materials and the development of new green packaging materials are an urgent task. Caused by the plastic packaging materials production enterprises attach great importance. At present, there are new breakthroughs in this area at home and abroad.

1. Degradable plastics have been completely degraded from incomplete degradation to biological development

The degradation caused by the addition of starch to the original polyolefin is an incomplete solution, and polylactic acid is a new type of degradable plastic that has risen in recent years. It is recognized internationally as a new type of packaging material with promising development, and is an obvious environmental protection material. It is stable at room temperature, but above 55°C, it will be decomposed automatically under the influence of oxygen and microorganisms. After use, the waste can be completely degraded by microorganisms and will not cause pollution to the environment, which is very beneficial to the protection of the environment. In 2004, 13 Asahi Kasei companies, the United States, France, and German companies all made polylactic acid and obtained polylactic acid films and boxes. In June 2004, China's Taizhou Hisun Group developed polylactic acid (PLA) to enter the industrialization stage. In July 2004, Toray announced the successful development of a biaxially stretched polylactic acid film. These all show new breakthroughs in new environmentally friendly materials and packaging technologies. However, the current high cost of polylactic acid constrains development.

2. Development of degraded foams using carbon dioxide

At present, the total amount of carbon dioxide produced and discharged by industrial production processes in the world exceeds 24 billion tons each year, of which 15 billion tons are absorbed by plants, while a net increase of 9 billion tons has become the main waste gas polluting the environment and endangering human living space. Global climate anomalies caused by carbon dioxide-based greenhouse gases, such as El Niño, and the resulting reduction in grain production and desertification in the world have attracted widespread attention. The comprehensive utilization of carbon dioxide has thus become a global research and development hotspot, and the utilization of carbon and oxygen elements in carbon dioxide to make plastics has become one of the most concerned technologies. Jiangsu Jinlong Green Chemical Co., Ltd. uses the patented technology of the Guangzhou Institute of Chemistry of the Chinese Academy of Sciences, and uses carbon dioxide as raw material to produce 2,000 tons of aliphatic polyethylene carbonate and a biodegradable polyurethane foam industrialization project based on the resin. It passed the country in Taixing. SEPA organizes the appraisal. This technology has independent intellectual property rights. Experts believe that the catalytic activation technology of carbon dioxide and the high biodegradability of polyurethane foam have reached the international advanced level.

The use of technology can produce about 3 tons of aliphatic polyethylene carbonate resin per ton of carbon dioxide consumed, and produces about 6 tons of degradable polyurethane foam. The product has excellent performance; it can not only replace ordinary packaging materials and heat insulation materials for construction in the market, but also can be used as a packaging material with high electrical and environmental protection requirements.

3. Develop water-soluble film

The main raw materials of water-soluble packaging films are low alcohol alcohols and polyvinyl alcohol, which have good film-forming and water-soluble properties. The final products of PVA film degradation are co2 and H2o, which can solve the problem of packaging waste disposal. Due to the environmental protection of water-soluble packaging films, it has received wide attention from countries around the world.

Cai Mingchi Source: "New Chinese Packaging"