What do you know about the tension of plastic film?

How to test the tension of plastic film? What is the tension limit of plastic film? The surface tension of the plastic film depends on the surface free energy of the plastic film, and the free energy on the surface of the agricultural plastic film depends on the molecular structure of the film material itself. Most plastic films such as polyolefin films (LDPE, HDPE, LLDPE, PP) are non-polar polymers, with small surface free energy and low surface wet tension, generally about 30 dyne / cm. Theoretically, if the surface tension of the object is less than 33 dyne/cm, ordinary inks or adhesives cannot adhere firmly, so they must be surface treated. Polyesters (PET, PBT, PEN, PETG) are polar polymers with high surface free energy and a surface wet tension of more than 40 dyne/cm. However, for high-speed color printing or to increase the adhesion between the vacuum aluminized layer and the surface of the BOPET film, the BOPET film also needs to be surface treated to further improve its surface wet tension.