![]() The demand for plastic has extensively increased due to its unique mechanical and physical properties (e.g., light weight, strength, resistance to corrosion and chemicals) and low manufacturing cost. Polycarbonate plastic has a low thermal conductivity (k) and, therefore, is better than conventional glazing agents. They are used in construction materials (e.g., windows, panels, glazing, coatings, siding, roofing, flooring, fencing, and decoration), furniture, offices, agriculture (e.g., mulch film, materials for greenhouses, and production of sacks), transportation (e.g., bodywork and production of protective coatings), flame and smoke retardants (high content of chlorine 57% by weight), insulators, and others. ![]() Plastics are highly involved in our daily lives, from household items to very complex medical equipment. Ultraviolet absorbers are cheap to produce, can be used in low concentrations, mix well with polymers to produce a homogenous matrix, and do not alter the color of polymers. Plastic ultraviolet photostabilizers act as efficient light screeners (absorbers or pigments), excited-state deactivators (quenchers), hydroperoxide decomposers, and radical scavengers. Therefore, attention is paid to the design and use of safe, plastic, ultraviolet stabilizers that do not pose a danger to the environment if released. Plastics have many benefits, while on the other hand, they have numerous disadvantages, such as photodegradation and photooxidation in harsh environments and the release of toxic substances due to the leaching of some components, which have a negative effect on living organisms. Photodegradation deteriorates both the mechanical and physical properties of plastics and affects their predicted life use, in particular for applications in harsh environments. The photooxidative degradation process of plastics caused by ultraviolet irradiation leads to bond breaking, crosslinking, the elimination of volatiles, formation of free radicals, and decreases in weight and molecular weight.
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