Azo-peroxide free radical initiators containing ultraviolet light stabilizing groups

A free radical initiator containing ultraviolet light stabilizing groups having the formula:

• (R--X--X).sub.n R'
• wherein
• n is 2 to 4 with the provisos (a) through (e) recited below:
• a. at least one --X--X-- is --O--O-- and at least one --X--X-- is --N=N--;
• b. where R--X--X-- is R--N=N--, R is selected from the group consisting of alkyl 1-20 carbons, cycloalkyl of 3-10 carbons, aralkyl of 7-20 carbons, and ##STR39## wherein Y is selected from the group consisting of NC--, N.sub.3 --, ##STR40## wherein R.sub.1 and R.sub.2 are selected from the group consisting of alkyl of 1-20 carbons, cycloalkyl of 3-6 carbons, and alkylene of 2-30 carbons when R.sub.1 and R.sub.2 are joined together;
• and wherein one but not both of R.sub.1 and R.sub.2 can in addition be phenyl, tolyl, xylyl, benzyl, or phenethyl;
• R.sub.3 is t-alkyl of 4-8 carbons, t-cycloalkyl of 4-8 carbons, or t-aralkyl of 9-15 carbons;
• R.sub.4 and R'.sub.4 are alkyl of 1-6 carbons, cycloalkyl of 3-6 carbons, or aryl of 6-12 carbons;
• c. where R--X--X is R--OO--, R is selected from the group consisting of hydrogen, acyl of 2-20 carbons, aroyl of 7-20 carbons, t-alkyl of 4-12 carbons t-cycloalkyl of 4 12 carbons, t-aralkyl of 9-15 carbons, alkoxycarbonyl of 2-20 carbons, cycloalkoxycarbonyl of 4-20 carbons, carbamoyl, phenylcarbamoyl, alkylcarbamoyl of 2-13 carbons, cycloalkylcarbamoyl of 4-13 carbons, .alpha.-hydroxy-alkyl of 2-10 carbons, .alpha.-hydroxy-cycloalkyl of 3-10 carbons, .alpha.-hydroperoxyalkyl of 2-10 carbons, .alpha.-hydroperoxycycloalkyl of 3-10 carbons, alkylsulfonyl of 4-20 carbons, cycloalkylsulfonyl of 3-12 carbons, t-alkoxyalkyl of 4-20 carbons, t-alkoxycycloalkyl of 4-20 carbons, Q.sub.3 M--, Q.sub.2 M',
• wherein
• M is selected from silicon, germanium, or tin;
• M' is boron;
• and
• Q is alkyl of 1-11 carbons, phenyl, benzyl or cyclohexyl;
• d. R' ia a di, tri or tetravalent radical composed of a combination of two different components for linking the --OO-- and --N=N-- groups,
• (i) when R' is a divalent radical, R' is a combination of a R'.sub.a and a R'.sub.b wherein the component of R'.sub.b for connecting the --OO-- linkage is selected from those radicals listed under step (c) except hydrogen, carbamoyl, diethylphosphate, dimethylphosphate, diphenylphosphinic, di-n-octylphosphate and dibutyl phosphinic and the component R'.sub.a for connecting the --N=N-- linkage is selected from those radicals listed under step (b);
• and in addition the component of R'.sub.a for connecting the --N=N-- linkage can be selected from aryl of 6-14 carbons, acyl of 2-20 carbons, aroyl of 7-20 carbons, alkylcarbamoyl of 2-7 carbons, cycloalkylcarbamoyl of 4-11 carbons, alkoxycarbonyl of 2-7 carbons, cycloalkoxycarbonyl of 4-11 carbons and aryloxy carbonyl of 7-13 carbons;
• ii. when R' is a trivalent radical R' is defined as a combination of two R'.sub.a and one R'.sub.b or two R'.sub.b and one R'.sub.a wherein the subscripts a and b are in any order and the components of R' can be selected from a combination of the moieties listed under (i) above,
• iii. when R' is tetravalent radical, R' is defined as a combination of two R'.sub.a and two R'.sub.b or three R'.sub.a and one R'.sub.b or one R'.sub.a and three R'.sub.b wherein the subscripts a and b can be in any order and the components of R' can be selected from a combination of the moities listed under (i) above;
• e. and at least one of R and R' contains an ultraviolet light stabilizing radical of a compound selected from the group consisting of:
• ##STR41## where R.sub.6 is alkyl of 1-6 carbons.