The Properties Of Stretch Wrapping Film

When the stretch film is stretched, the load increases rapidly, and when the yield point is exceeded, the film is permanently deformed. In this plastic range, the stress-strain curve is generally flat. The final tensile load continues to increase until the breaking point is reached. At this point the load drops to zero. It should be said that the theoretical stress-strain curve of the wrapping film is similar to that of a stretched rubber ring. The yield point of the latter coincides with the rupture point. In this way, from the fact that the rubber ring can fasten the package, it can be inferred that the wrapping film can also tightly wrap the package after stretching.

When wrapping the goods with the wrapping film, the wrapping film is generally stretched in advance before contacting the goods, so that the film is subjected to a constant stretching force before wrapping the goods. And make the stretching force evenly distributed over the entire width of the film. Its pre-stretch rate can reach 200-300%. Therefore, the strength of the film is improved, the creep resistance at room temperature is also greatly improved, and it can also be stretched at the edges and corners of the goods. For different brands of stretch film, users can freely adjust the stretching force.