Alkanolamine ester of 1,1-biphenyl-2,2-diyl-and alkylidene-1,1-biphenyl-2,2-diyl-cyclic phosphites

A composition of matter comprising an organic material subject to oxidative, thermal and actinic degradation stabilized with an effective stabilizing amount of a compound corresponding to the formula ##STR21## wherein m, n and p are each 1, m is 2 and n is 1 and p is 0 or m is 3 and n and p are 0, and wherein

• R is alkyl of from 1 to 18 carbon atoms,
• R.sup.1 is hydrogen or alkyl of from 1 to 18 carbon atoms,
• R.sup.2 is a direct bond or alkylene of from 1 to 12 carbon atoms,
• A is alkylene of from 1 to 6 carbon atoms, or cycloalkylene of 5 to 6 carbon atoms,
• R.sup.3 is alkyl of 1 to 18 carbon atoms, or ##STR22## wherein Y is ##STR23## A' is alkylene of 1 to 6 carbon atoms or cycloalkylene of 5 to 6 carbon atoms,
• m' is 1 or 2,
• p is 0 or 1, and
• q is 0-5,
• with A, R, R.sup.1, R.sup.2 being as previously defined;
• provided that when p and q are 0, -N-A'-N can be a diazacycloalkyl group of 2 to 10 carbon atoms, or
• when m is 1 and p is 0, N-R.sub.3 is a azacycloalkyl group of 2 to 10 carbon atoms or an azaoxacycloalkyl group of 3 to 7 carbon atoms;
• and
• R.sup.4 is alkyl of 1 to 18 carbon atoms;
• together with a phenolic antioxidant selected from the group consisting of 6,6'-ethylidene-bis(2,4-di-tert.butylphenol), 6,6'-methylene-bis(2,4-di-tert.butylphenol) and 1,3,5-tris(4-tert.butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanurate.