Stabilized synthetic polymer compositions

Claim 1

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 ##SPC15## wherein n represents 1 or 2, R a , R b , R c and R d represent a methyl group, and R 1 represents, when n = 1, an alkyl group having 4 to 12 carbon atoms; an alkenyl group having 3 to 10 carbon atoms; an alkynyl group having 3 or 4 carbon atoms; a benzyl group optionally substituted with 1 to 3 substituents, which may be the same or different, selected from chlorine, an alkyl having 1 to 4 carbon atoms, an alkoxy having 1 to 8 carbon atoms and hydroxy in its phenyl moiety; phenethyl group; 2,3-epoxypropyl group; or a group of the formula --CH.sub.2 --CO.O--R.sub.2, wherein R 2 represents an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 3 to 6 carbon atoms, phenyl group, benzyl group, cyclohexyl group or 2,3 epoxypropyl group; or a group of the formula ##EQU1## wherein R 3 represents hydrogen atom, methyl group or phenyl group; R 4 represents a hydroxy group or a group of the formula --O.COR 5 ; R 5 represents an alkyl group having 1 to 17 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, a phenyl group optionally substituted with 1 to 3 substituents, which may be the same or different, selected from chlorine, an alkyl having 1 to 4 carbon atoms, an alkoxy having 1 to 8 carbon atoms and hydroxy, benzyl group, 3,5-di-tertiary butyl-4-hydroxyphenethyl group, styryl group or cyclohexyl group; or R 1 may be a group of the formula --CO--R.sub.6, wherein R 6 represents a hydrogen atom, methyl group, an alkenyl group having 2 or 3 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, benzyloxy group or phenoxy group; and when n = 2, R 1 represents an alkylene group having 1 to 6 carbon atoms in which the alkylene chain may optionally be interrupted by an oxygen atom; 2-butenylene group; or a group of the formula --CH.sub.2 CO.O--R.sub.7 --O-COCH.sub.2 --, wherein R 7 represents an alkylene group having 2 to 6 carbon atoms or xylylene group; or a group of the formula --CH.sub.2.CH.sub.2 --O.CO -- R.sub.8 ).sub.m CO.O--CH.sub.2.CH.sub.2 -- wherein m represents 0 or 1; R 8 represents an alkylene group having 1 to 10 carbon atoms in which the alkylene chain may optionally be interrupted by a sulfur atom; an alkenylene group having 2 to 4 carbon atoms, a phenylene group or 1,4-cyclohexylene group.