The UV radiation absorbed by plastics can excite photons, which then create free radicals. Even though pure plastics cannot absorb UV radiation, the presence of catalyst residues and other impurities can act as receptors and cause their degradation. A very small amount of impurity is enough to initiate color instability, for example, traces per billion sodium values in polycarbonate. In the presence of oxygen, free radicals form oxygen hydroperoxides that can break the double bonds of the main chain, leading to a brittle structure.
This process is known as photooxidation. Even in the absence of oxygen, degradation will still occur due to the cross-linking process, which is the effect of the plastics used in the Hubble Space Telescope and the International Space Station. UV resistance comes in three forms: additives, plasticizers, and printed products. By using these three forms, plastic films can better withstand harmful UV rays.
The competition between cracking and homogeneous performance of plastic (associated with macroscopically ductile behavior) depending on material parameters and external variables such as temperature has been one of the main focuses of research on the microdeformation behavior of amorphous and semicrystalline polymers. This research has been driven by the need to understand and control the fracture and impact resistance of plastic components in many applications. Manufacturers can control the UV resistance of plastic films by adding different types of additives such as antioxidants and plasticizers. These additives can help improve the performance of plastic films by increasing their resistance to UV radiation. Additionally, manufacturers can also use printed products that are designed to better withstand UV rays. In conclusion, manufacturers can control the UV resistance of plastic films by adding different types of additives such as antioxidants and plasticizers.
Additionally, they can also use printed products that are designed to better withstand UV rays. By doing so, they can ensure that their plastic films are able to withstand harmful UV radiation.
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