Principle of air permeability of stretch wrapping film

 The air permeability of the stretch wrapping film is one of the important properties of the stretched film. The correct adjustment method is to adjust the amount of LLDPE to a suitable viscosity, and you can also add PIB or other master batches. It takes a period of time to move out, but it is also affected by temperature.


When the temperature is high, the viscosity is strong, when the temperature is low, the stretch and viscosity are low. The viscosity of the stretch film is greatly reduced after stretching, so a certain temperature needs to be controlled, and the air permeability of the stretch film also determines its quality Important indicators.


How to improve the breathability of stretch wrapping film?


Generally speaking, the gas permeability and gas permeability coefficient are the main indicators to measure the permeability. The gas permeability at a constant temperature determines the air permeability of the film. You can also use the test to set a high-pressure chamber and a low-pressure chamber, test and seal them separately, and then use the pressure change in the low-pressure chamber on the manometer side.


Among them, pay attention to the pressure difference between high pressure and low pressure. The inspection process is carried out under the pressure difference condition of the low pressure chamber. To check the accuracy of the test data, how to maintain the air permeability of the stretched film must pay attention to the sealing of each system in the process instrument Sex.


If you want to know more about stretch film, please feel free to contact us, we will get back to you as soon as possible.

stretch wrapping film

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