First, plastic packaging materials
1. It has the characteristics of light weight, convenient use, good barrier property, permeability, heat resistance, cold resistance and corrosion resistance, as well as colorful appearance and beautiful appearance. Because of its abundant raw materials, low cost and excellent performance, it has been widely used in food packaging, and has gradually replaced traditional packaging materials such as glass, metal and paper, which has greatly changed the appearance of food packaging. It is worth noting that plastic packaging materials have a prominent shortcoming that is not easily degraded, and incineration produces toxic gases. Moreover, plastic packaging materials belong to the shortest period of use in plastic products, generally 1 month to 3 months, the longest one year. After that, most of them become urban solid waste into the garbage disposal system, and some are randomly discarded, resulting in "white." Pollution".
2. Plastic packaging materials account for the largest proportion of waste, and the pollution caused by the environment is also the most serious among various packaging materials. The current treatment scheme combines recycling and development of degradable plastics. In addition, due to the defects of plastic products, their moisture resistance and barrier properties are not as good as metal and glass containers. Therefore, the performance of existing plastics is improved, new varieties are developed, strength and barrier properties are improved, dosage is reduced, and reuse and sorting are recycled. It is very important.
Second, paper packaging materials
1. In the modern packaging industry system, paper and paper packaging containers occupy a very important position, accounting for 40% to 50% of the total packaging materials. Compared with other materials, it has a series of unique advantages: good processing performance, excellent printing performance, certain mechanical properties, easy compound processing, good lineability, good health and safety, and wide range of raw materials, variety, and low cost. It is easy to form large-scale production. The paper packaging container is light in weight, good in cushioning, widely used, and waste can be recycled and used without white pollution. With the enhancement of environmental awareness and the actual needs of life, the development of plant fiber snack boxes and the development of natural green packaging materials will be the future trend of paper packaging materials.
Two. In addition, with the rapid development of packaging technology, edible packaging paper is an important development direction of modern food packaging. This packaging has important environmental and economic value. At present, there are two kinds of edible papers abroad, one is to use vegetables as the main raw material, and the vegetables are shaped and dried; the other is to gelatinize starch and sugar, add other food additives, and strive to form a similar method to papermaking. From the perspective of application and development, green products based on vegetables have more potential for development.
Third, metal packaging materials
The excellent performance of metal packaging materials includes: high barrier property, excellent mechanical properties, good processability of container molding, good high and low temperature resistance, thermal conductivity and thermal shock resistance, good surface decoration and easy packaging waste. Recycling treatment. Canned foods, as well as some liquid, paste, powder or high-grade foods. Commonly used metal packaging materials are tinplate and aluminum, which are widely used in the manufacture of food and beverage packaging cans.
