1.Analysis of the change mechanism of peel strength with time
No matter how high the surface gloss is, there are many tiny pores that are hard to see with the naked eye. Although the pressure-sensitive adhesive is cross-linked, it still has certain deformation and fluidity, especially the polymer part that does not participate in the cross-linking. With the extension of time, the pressure-sensitive adhesive gradually penetrates into the open space to form an "anchor". In addition, when the pe protective film is attached, although the pressure is large, the contact area between the pressure-sensitive adhesive and the surface of the material is not very large. The force is also gradually improved. Both effects will increase the peel strength with the elongation of time.



2. Analysis of aging mechanism
The main chain of acrylate pressure-sensitive adhesive is a full chain, and it is difficult for the main chain to be broken by ordinary heat energy. The aging mechanism is mainly ultraviolet light aging; the substrate aging is also mainly ultraviolet light aging. Guanrong Adhesive has previously tested the tensile strength of PE film substrates after aging at 80 ℃ and 30W UV light for 1 week. The results show that the usual use temperature has little effect on its aging performance, while the UV The impact is greater. But under the action of heat and ultraviolet light, there is a synergistic aging effect.





3. Analysis of the compatibility mechanism with the protected surface data
Acrylic pressure-sensitive adhesives are classified as materials with high polarity, and are easily compatible with polar materials such as acrylates, polyesters, and polyurethanes, and form a pe protective film that is difficult to remove. Sometimes the small molecules of the pressure-sensitive adhesive that are not cross-linked will be enriched on the surface. If the force between the protected surface material and these small molecules is large, the phenomenon of small molecule migration and residue will appear.


4. Analysis of Viscoelastic Effect Mechanism
Pressure-sensitive adhesives belong to viscoelastic materials, which undergo elastic deformation and plastic deformation under the action of external force. When the force velocity is fast, the elastic deformation takes the lead; when the force velocity is slow, the plastic deformation takes the lead. If the protective film is quickly removed, the pressure-sensitive adhesive will undergo elastic deformation, and the pressure-sensitive adhesive touched by the protective surface will not be able to detach from the surface, resulting in adhesive residue. According to the principle of time-temperature equivalence, the effect of removing the protective film at low temperature is similar to that of quickly removing the protective film