The ever-increasing upgrade of commodity packaging around the world has caused a tremendous amount of wasted resources. The abuse of plastic products has also placed a tremendous burden on waste disposal. In the United States, waste plastic accounts for 20% of domestic waste, mainly bags and containers. It takes more than a century for plastic bags and packaging boxes to decompose, causing serious environmental pollution. At the same time harmful ingredients in some food packaging materials can also cause harm as food enters the body. For this reason, in order to save resources and protect the environment, some countries have begun to study various methods to solve the packaging problem. The ideal that they hope to achieve is zero packaging, that is, packaging methods that do not produce any rubbish.

Research institutes around the world, especially some large companies, have started to research packaging materials that can be recycled or that can be rapidly decomposed under natural conditions. For example, Bayer, a well-known German chemical scientist in the chemical industry, has successfully developed a decomposable plastic that can be converted into compost. All kinds of packaging products made of this plastic can be quickly disintegrated after being thrown away, return to nature, and do not cause any pollution to the environment. The scientists mixed a tough and not easily stretchable polyurethane with a synthetic leather to make a new plastic material. When this cellulose-containing decomposable plastic material is disposed of and buried in human soil, it becomes a delicious food for the microorganisms in the soil. Microbes multiply and rapidly ingest plastics and turn it into humus in just 10 days. No adverse effects on the soil, microorganisms, algae, fish, etc. This decomposable plastic can be used in garbage bags, medical containers and various types of packaging, even children's diapers and burial wreaths. The pots made in the buried soil can even act as compost after the decay, so that the planted seedlings grow twice as long as the flowers in the traditional pots, and the blooms are more beautiful.

The Latham Company of France uses biological effects from plant and animal sources to form a 100% biodegradable plastic. The polymer costs 20 francs to 25 francs per kilogram, which is 10 times cheaper than the best materials available today. This biodegradable packaging material is buried underground or in lakes and can be completely transformed into carbon dioxide, water and humus.

Another type of zero-degree packaging material is made from starch as a raw material, such as a German invented starch packaging cup that will not melt liquid, can hold beverages, dairy products and other foods, after the food can be cups together Eat it. This invention has enabled Germany to save an annual 4 billion plastic cups of materials and the corresponding disposal costs. The fast food box that Norway introduced at the 1994 Lillehammer Winter Olympic Games is also a starch package that can be eaten together with food. A film invented in the United Kingdom for food and fruit preservation can dissolve in water within 10 minutes. The United States has also succeeded in developing a plastic bag made of starch and synthetic fiber, which can be decomposed into water and carbon dioxide in nature.

All kinds of zero-degree packaging materials mentioned above have strict requirements and goals during the test, that is, the materials and additives as well as the decomposed products must be harmless to the environment, and can even meet the edible standards that do not harm human health. Contains water, carbon dioxide and humus; the product is of good quality and reasonable price, and it is easy to realize commercial production.

At present, the new fashion in the international commodity packaging market is the substitution of paper for plastic packaging products instead of bag packaging products. In particular, paper packaging made of recycled paper, which is known as “green packaging”, has become the leading product in the daily-use packaging market, and it has gradually covered the packaging industry. According to the food packaging industry, paper packaging bags will gradually replace traditional packaging bags, sacks, and plastic bags. The material used to make paper bags is a kind of stretch paper bag. Compared with plain paper, the strength is 15 times higher. A bag full of 25 kilograms of flour is composed of four layers of stretch paper, free from a height of 15 meters. Falling 15 times is still not broken. The prominent advantages of paper bag packaging foods are non-toxic, odorless, non-polluting, and meet food hygiene standards. The tightness of the paper bag is better than that of the cloth bag, which can prevent extravasation of flour and prevent the intrusion of dust. Under the same conditions, the shelf life of flour in paper bags can be extended by 2 months to 3 months compared to cloth bags.

Xue Fulian

Source: China Packaging Industry