MONO- AND BIS- BENZOTRIAZOLYLDIHYDROXYBIARYL UV ABSORBERS

摘要

Provided is a composition which contains a mono- or bis-benzotriazole compound, an N-oxide thereof, or a mixture of at least two of the preceding compounds. Representative bisbenzotriazole compounds include 3,3'-bis-(2H-benzotriazol-2-yl)-5,5'-di-tert-octyl-1,1'-biphenyl-2,2'-diols. Representative mono-benzotriazole compounds include 3-(2H-benzotriazol-2-yl)-5,5'-di-tert-octyl-1,1'-biphenyl-2,2'-diols. These mono- and bis-benzotriazole compounds are useful as stabilizers of degradable polymers against the degradative action of ultraviolet light. Also provided is a method of making these benzotriazole compounds by oxidative dimerization of the corresponding monomeric benzotriazole or by reductive cyclization of the corresponding azo- compound. A degradation stable composition containing a degradable polymer and a benzotriazole compound disclosed above and a method of stabilizing a degradable polymer are also provided. Among the many polymers which may be stabilized using these stabilizers are the following : polycarbonate, polyester, polyethylene, polypropylene, polystyrene, polyacrylate, polyamide, polyurethane, and aminoresin-crosslinked polymers.