Factors that affect the elongation of stretch film

The main function of stretch film is to stabilize, conceal and maintain goods, is a very common packaging method in the world, it has outstanding transparency, shortening and certain shortening stress, can allow customers to directly see the packaged goods, convenient for customers to choose goods, in the production of its stretch rate affected by what?
Stretch film generally does not use longitudinal stretching, its elongation is limited by the polymer through the use of copolymer or mixed with some metallocene PE, because the wide molecular weight distribution makes it tensile strength is relatively poor, the structure of the polymer will change, such a limit elongation rate, thereby enhancing its performance, longitudinal stretching can open the pores that give the product air permeability, these stretch films are filled with calcium carbonate and other minerals, through a cooling roller to cool it quickly, after longitudinal stretching, This is followed by a greater degree of longitudinal stretching, which separates the polymer from the filled mineral particles to open the vents.