| abstract |
Compounds of formula I <IMAGE> (I) wherein n is 2-4, R1 is alkyl, cycloalkyl, phenylalkyl, phenyl or a radical of formula II <IMAGE> (II) R2, R3 and R4 are independently hydrogen, alkyl, cycloalkyl, phenylalkyl or aryl, or R3 and R4 together are alkylene, R5 and R6 are independently hydrogen, alkyl, cycloalkyl or phenylalkyl, R7 is hydrogen, alkyl or a group of the formula -(CH2)kCOOR8, where k is 0-2 and R8 is hydrogen or alkyl, and T is an n-valent hydrocarbon radical which may be interrupted by heteroatoms, are useful stabilizers for substrates subject to the deleterious effects of oxygen, heat and/or actinic radiation. |