UV stabilizers in plastics

UV stabilizers are used frequently in plastics, including cosmetics and films. The primary function is to protect the substance from the long-term UV degradation effects from ultraviolet radiation. Different UV stabilizers are utilized depending upon the substrate, intended functional life, and sensitivity to UV degradation.

UV stabilizers, such as benzophenones, work by absorbing the UV radiation and preventing the formation of free radicals. Depending upon substitution, the UV absorption spectrum is changed to match the application. Concentrations normally range from 0.05% to 2%, with some applications up to 5%.

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