With its good flexibility, self-adhesion and high transparency, film is widely used in the packaging of various products. Its performance is affected by many factors, including raw materials, production process, use of additives and storage environment.

Raw material factors:

The main raw material of the stretch film is polyethylene (PE), including linear low polyethylene (LLDPE), low polyethylene (LDPE) and so on. The molecular structure and molecular weight distribution of different types and grades of polyethylene are different, which will directly affect the tensile strength, elongation at break, self-adhesion and other properties of the stretch film. For example, LLDPE has higher tensile strength and toughness, which makes the stretched film less likely to break during stretching and more tightly wrapped.

Production process factors:

The production process plays a key role in the performance of the stretch film. Extrusion temperature is one of the important parameters, the temperature is too high will lead to material degradation, so that the strength of the stretched film is reduced, the color turns yellow; the temperature is too low will make the material plasticization, affecting the flatness and tensile properties of the film. The cooling rate also affects the crystallinity of the film, which in turn affects its mechanical properties. In addition, the stretching ratio determines the degree of stretching and molecular orientation of the stretched film, and a reasonable stretching ratio can improve the tensile strength and toughness of the film.

Additive factors:

In order to improve the performance of the stretched film, some additives are usually added, such as tackifiers, antistatic agents, anti-aging agents, etc. The tackifier can improve the self-adhesion of the stretched film and make it better to wrap the goods; the antistatic agent can reduce the static electricity generated during the production and use of the stretched film and avoid the adsorption of dust; the anti-aging agent can delay the stretched film The aging speed under the action of light, oxygen, etc., prolongs its service life.

Storage environment factors:

Stretch film should be stored in a dry, ventilated and cool environment, away from direct sunlight and high temperature. Long-term exposure to high temperature environment will cause thermal aging of the stretch film, resulting in performance degradation; while humid environment may cause the stretch film to absorb moisture, affecting its self-adhesion and electrical insulation properties.