Reasons for poor viscosity of polymer protective film

When a polymer protective film is used, it may be difficult to adhere. From the analysis of the protective film material itself, there are four reasons why it is difficult to adhere. 1. Crystalline polymers have high crystallinity and good chemical stability. Compared with amorphous polymers, they are difficult to swell and dissolve. When the solvent-based adhesive is pasted on the surface of difficult-to-bond materials, it is difficult to polymerize the polymer chains. Chain formation, mutual diffusion and entanglement cannot form strong adhesion. 2. The polyolefin resin itself contains low-molecular-weight materials, and additives are added during processing. Such low-molecular-weight materials are very easy to precipitate and aggregate on the surface of the resin, forming a weak interface layer with low strength, resulting in poor adhesion. Post-processing, such as printing, laminating and bonding. 3. The surface energy is low, and the critical surface tension is generally 31 to 34 cm. Due to the low surface energy and large contact angle, the polymer film cannot fully wet the substrate and therefore cannot adhere well to the substrate. 4. Polyolefins, fluororesins, etc. are all non-polar polymer materials, and polyethylene molecules are basically non-polar polymers and non-polar polymers. For the surface of the non-polar polymer material, the conditions for the formation of orientation force and induction force are not provided, but only weak dispersion force is formed, so the adhesion is poor. Starting from the material itself, the continuous improvement of development technology can avoid the difficulty of adhesion of the adhesive film. When buying on the market, you need to carefully choose a high-quality polymer protective film. Next: Understand the role of electrostatic protective film Previous: Advantages of PE heat shrinkable film