Analysis of environmental protection problems in p

in recent years, with the continuous improvement of China's material processing technology, flexible packaging has been widely used in food packaging, seafood packaging, industrial packaging, commodity packaging, drug packaging, clothing packaging, etc. flexible packaging has become one of the fastest growing industries in China's plastic industry. The domestic demand for plastic film in flexible packaging has increased at a rate of 9% per year, and the annual growth rate has been maintained at about 15%. In 2007, The amount of plastic flexible packaging in China is about 4.5 million tons. In addition, China has a great demand for sterile flexible packaging, and many new types of flexible packaging have not yet been developed. For example, fresh meat preservation packaging and low-temperature preservation have not been popularized in China, nor has an industrial chain been formed, and the preservation of vegetables and fruits is almost blank. According to the prediction of relevant departments and experts, the packaging of dairy products, fresh meat, vegetables, fruit juice, beverages and seasonings in China will have a great development in the next 5 ~ 10 years. The best packaging for this kind of products is sterile packaging. In addition, aseptic flexible packaging for vegetables, alcohol and other products also needs to be developed, which indicates that the demand for flexible packaging will grow rapidly. It is estimated that the annual demand for all kinds of plastic flexible packaging films in China will reach 5.4 million tons by 2010

in January 2008, the State Council issued the notice of the general office of the State Council on restricting the production, sale and use of plastic shopping bags, which stipulates that from June 1 this year, the production, sale and use of plastic shopping bags with a thickness of less than 0.025 mm will be prohibited nationwide. This measure is of great significance to reduce the waste pollution of thin plastic bags. At present, this measure has been implemented in major cities. The author believes that the countermeasures against pollution caused by plastic flexible packaging printing can also be considered from the following aspects:

1. Actively develop and apply green gravure printing ink with compound environmental protection requirements

water based ink with water as solvent is a world recognized environmental protection ink, and it is also the only ink recognized by the American food and drug association among all printing inks at present. In the United States, 80% of gravure prints use water-based ink, and other economically developed countries (such as Japan, Germany, France, etc.) use more and more water-based ink in plastic films. Compared with solvent based gravure printing ink, water-based ink has the advantages of environmental protection, safety, low ink consumption and low cost. The amount of water-based ink used in China is still very small. If the comparison voltage of the two operational amplifiers is abnormally small, the annual demand is about 100000 tons, but the amount of water-based ink used for packaging and printing products is increasing every year

the new alcohol soluble gravure printing ink uses edible alcohol as the solvent, which is safe, non-toxic, environmental friendly and hygienic. It is an ideal substitute for traditional plastic gravure printing ink. Under the condition that the technical conditions of water-based ink are not particularly mature at present, the selection of alcohol soluble ink is the first choice of many plastic printing factories. Although alcohol soluble inks more or less use some lipids or other types of solvents as diluents, which is not really environmentally friendly inks, it is an important transitional product for gravure inks to transition from traditional solvent based inks to water-based inks. At present, many domestic enterprises are developing and applying new alcohol soluble inks

in addition, UV gravure ink and soybean ink are also relatively environmentally friendly inks. At present, UV gravure decorative inks with fast curing speed, good consistency of prints and thick ink layer have been produced in China, but the high cost of UV gravure inks limits their large application in plastic gravure printing. In short, alcohol soluble inks and water-based inks with low VOC emissions will become more and more popular in plastic gravure printing, and have a broad market prospect

2. Actively develop and apply degradable green packaging film

edible packaging film, such as chitosan edible packaging film, corn protein packaging film, modified cellulose edible packaging film and composite edible packaging film, which can be used for the inner packaging of various foods, such as the packing of candy and sticky cakes, or making casings Guoyi Clariant said that its cooperation with SABIC in high-performance materials business will significantly improve profits and capsules. It caters to the fast and convenient trend of modern consumption and has a large market in the food industry. In recent years, countries all over the world have made great progress in the research of edible film, and the application of edible film is more and more extensive. However, at present, edible film still has some shortcomings, such as poor processability, mechanical strength, protective function and high cost, compared with plastic film

degradable films not only have the functions and characteristics of traditional plastics, but also can be split and degraded in the natural environment through the action of microorganisms in soil and water or through the action of ultraviolet rays in sunlight after reaching the service life, and finally re-enter the ecological environment in the form of reduction and return to nature. The varieties developed in China have covered photodegradation, photodegradation, photooxidative biodegradation, high starch content biodegradation, high calcium carbonate filled photodegradation, full biodegradation, etc

water soluble film refers to the film that can be dissolved in water at room temperature. As a new green packaging material, it is widely used in the packaging of various products in Europe, America, Japan and other countries, such as pesticides, fertilizers, pigments, dyes, detergents, water treatment agents, mineral additives, detergents, concrete additives, photographic chemicals and gardening care chemicals. Water soluble films have been widely valued by developed countries in the world because of their environmental protection characteristics, such as complete degradation, safety and convenience. Among them, polyethylene oxide film is the most soluble water-soluble film

3. Establish and improve an effective recycling system

Plastic packaging recycling is the most active way to promote the recycling of materials, and it is an important means to effectively save raw material resources and energy and reduce the amount of packaging waste. At present, the recycling and reuse of plastic flexible packaging waste in China is very poor, showing the coexistence of weak recycling awareness, low recycling technology, disjointed recycling, high recycling difficulty and low recycling rate (less than 5%). Therefore, it is very necessary to establish a complete set of perfect and effective recycling channels and systems to enhance the recycling awareness of large consumers, which makes the original high-efficiency and energy-saving advantages of thermal insulation materials disappear