Plastic packaging material requirements

Plastic is the fastest growing and most widely used material in aseptic packaging. Its low cost, diversified shapes, and strong mechanical adaptability, especially in recent years, the coextrusion of plastic film and the continuous development of container molding technology, promote The development of plastics in the field of aseptic packaging materials.

The requirements for plastic packaging materials mainly include the preservation and preservation of foods, the mechanical strength to adapt to circulation, the adaptability of packaging machines, and the commercial properties. In particular, it requires high barrier properties to oxygen and water vapor. Aseptic plastics used are mainly composite films.

The vast majority of plastic film production enterprises in China have not yet produced such aseptic packaging materials, and also lacked domestic materials with good polyvinylidene chloride barrier properties; in the manufacture of aseptic packaging containers, the lack of strict cleanroom conditions and Sterilization measures. Therefore, to develop aseptic packaging in China, packaging materials manufacturing is a very important part.

Due to poor heat resistance of plastics, the current sterilization methods for plastic packaging materials are often sterilized by hydrogen peroxide, and there are also technologies that combine hydrogen peroxide low concentration solutions with ultraviolet rays and sterile hot air. These methods are reported to be Good sterilization effect. In order to prevent hydrogen peroxide from diffusing in the operating environment, it is advantageous to use a low concentration of hydrogen peroxide.

In addition to the packaging containers and materials listed above, there are special materials involved in aseptic packaging, such as metal composites and containers, paper and metal composite containers. Moreover, with the increasing demand for food quality and the sustainable development of human living environment, packaging materials and containers are gradually going green and green, especially in the food packaging that people consume daily, they need to pay more attention to health and green. Therefore, the development of aseptic packaging containers will be an important issue that needs to be solved for the wide application of aseptic packaging technology, and its development will be mainly non-toxic, green, environmentally friendly, economical and practical as the main goal and direction.

In the use of packaging materials should pay attention to the sterilization of packaging materials (containers), commonly used sterilization methods are: sterilization of chemicals (such as hydrogen peroxide, ethanol, etc.), superheated steam sterilization, UV sterilization and so on. There are different defects in different sterilization methods, and suitable sterilization methods should be selected according to different materials. The kind of packaging material and its corresponding sterilization method determine the type, complexity and stability of the aseptic packaging system to a large extent.

In general, paper and plastic packaging containers can be sterilized by ultraviolet, hydrogen peroxide, ethanol, hydrogen peroxide+ultraviolet, ethanol+ultraviolet and other methods. For heat-sensitive plastic bottles, composite membranes and paper containers, radiation sterilization can also be used. Metals, glass packaging containers, metal lids, etc. are generally sterilized by thermal methods, superheated steam, hydrogen peroxide, heat, and other methods.

Sterilization of packaging materials and containers should be carried out in a reliable manner determined by rigorous testing. Since aseptic packaging containers use soft composite bags, consideration should be given to minimizing the effect of prolonged high temperatures on material quality. This is an important part of aseptic packaging and the key to the success or failure of aseptic packaging.