UV Absorbers

UV absorbers absorb UV radiation and dissipate it as heat in order to avoid photosensitization of the protected polymer. Chemical structures comprise mainly benzophenones, benzotriazoles, hydroxyphenyltriazines and oxanilides. Depending on their structure, polymer systems show different absorption peak in the UV spectrum; therefore, the UV absorbers should cover as broad a UV range as possible. Furthermore, combinations of various UV absorbers can be used with HALS stabilizers. Commercial grades like UV-326, UV-327, UV-328 and UV-360 provide protection by absorbing energy from UV radiation and, through a chemical mechanism, dissipate the energy to heat.