Introduction to a new class of high performance light stabilizers and the influence of light stabilizers structure on the polymer's life time

The mode of action of two classes of UV absorbers (2-(hydroxyphenyl)benzotriazoles and 2-(2'-hydroxyphenyl)-1,3,5-triazines) is discussed. Theoretical explanations for the superior light stability of the latter are given and confirmed by measured half life times in polycarbonate and solution. A mathematical model for the quantitative prediction of light protection factors is proposed.