Polymer compositions containing piperidine derivatives as stabilizers

A synthetic polymer composition stabilized against photo- and thermal deterioration wherein there is incorporated, in a sufficient amount to prevent said deterioration, a compound having the formula ##STR61## wherein R' represents

• an alkyl group of 1 to 20 carbon atoms,
• a hydroxyalkyl group,
• an alkenyl group having from 3 to 4 carbon atoms,
• a 2-propynyl group,
• a cyanoalkyl group,
• an alkoxyalkyl group,
• an alkenyloxyalkyl group,
• an aryloxyalkyl group,
• an alkylthioalkyl group,
• an epoxyalkyl group,
• an acyloxyalkyl group,
• an alkoxycarbonylalkyl group,
• an aralkyl group,
• 2-hydroxy-2-phenylethyl,
• a 2-acyloxy-2-phenylethyl group having 10 to 20 carbon atoms,
• an acyl group,
• an alkoxycarbonyl group,
• an aralkyloxycarbonyl group,
• an amino group,
• an acylamino group,
• an alkylamino group, or
• the nitroso group;
• X represents
• an oxygen atom, or
• a sulfur atom;
• Y represents
• an oxygen atom,
• a sulfur atom or
• a group of the formula .dbd.N--R" in which
• R" is a hydrogen atom,
• a methyl group,
• an allyl group,
• 2-propynyl group,
• 2-hydroxyethyl group,
• 2-methoxyethyl group, or
• a benzyl group;
• Z represents
• an oxygen atom, or
• a group of the formula .dbd.N-R'" in which
• R'" is a hydrogen atom,
• an alkyl group having 1 to 4 carbon atoms,
• an allyl group,
• 2-propynyl group,
• 2-hydroxyethyl group,
• an ethoxymethyl group,
• 2-vinyloxyethyl group,
• 2-phenoxyethyl group,
• 2-acetoxyethyl group,
• 2-benzyloxyethyl group, or
• a benzyl group;
• n is an integer of 1 through 4 inclusive;
• and
• R represents when n is 1, an alkyl group of 1 to 20 carbon atoms,
• a hydroxyalkyl group,
• an alkenyl group having from 3 to 4 carbon atoms,
• a 2-propynyl group,
• a cyanoalkyl group,
• an alkoxyalkyl group,
• an alkenyloxyalkyl group,
• an aryloxyalkyl group,
• an alkylthioalkyl group,
• an epoxyalkyl group,
• an acyloxyalkyl group,
• an alkoxycarbonylalkyl group,
• an aralkyl group,
• 2-hydroxy-2-phenylethyl group,
• a 2-acyloxy-2-phenylethyl group having 10 to 20
• carbon atoms,
• a 2,3-epoxypropyloxycarbonylalkyl group,
• an aryloxycarbonylalkyl group,
• an aryl group of 6 to 10 carbon atoms,
• a halogen or alkyl substituted phenyl or naphthyl group,
• a cycloalkyl group,
• an alkoxycarbonyl group,
• an aralkyloxycarbonyl group,
• a dialkoxyphosphine group,
• the diphenoxyphosphine group of the formula ##STR62## or a group of the formula ##STR63## (OR"").sub.2 in which R"" is an alkyl group of from 1 to 8 carbon atoms, or a phenyl group;
• when n is 2,a polymethylene group of 1 to 10 carbon atoms,
• a group of the formula --(CH.sub.2).sub.p --CH.dbd.CH--(CH.sub.2).sub.p -- in which p is an integer of 1 through 8 inclusive and the p's may be the same or different,
• an arylene group having 6 to 7 carbon atoms,
• a xylylene group of the formula ##STR64## an alkylenediphenylene group having from 13 to 15 carbon atoms, a bis-(alkoxycarbonyl)alkylene group of the formula ##STR65## in which p is as defined above and p.sub.1 is an integer of zero through 8 inclusive,
• a group of the formula ##STR66## in which p is as defined above, an alkylene-bis-(oxycarbonylalkyl)group of the formula ##STR67## in which p is as defined above, a dialkylene ether group or
• a diphenylene ether group;
• when n is 3, an alkanetriyl group,
• a tris-(alkoxycarbonyl)-alkanetriyl group of the the formula ##STR68## an alkanetriyl-tris-(oxycarbonylalkyl) group of the formula ##STR69## a group of the formula ##STR70## or a group of the formula ##STR71## in which p is an integer of 1 through 8 inclusive and the p's may be the same or different, and when n is 4, an alkanetetrayl group, a tetrakis-(alkoxycarbonyl)alkanetetrayl group, an alkane-tetrayl-tetrakis(oxycarbonylalkyl)group of the formula ##STR72## or a group of the formula ##STR73## in which p = 1 to 8.