Stabilization of polyether polyol, polyester polyol or polyurethane compositions
View Patent ↗The present invention pertains to compositions comprising (a) a polyether polyol, a polyester polyol or a polyurethane, (b) a UV-absorber of formula (I) and/or a hindered amine light stabilizer of formula (II) wherein R 1 and R 2 are each independently C 1 -C 4 alkyl or C 1 -C 4 alkyoxy, and (c) at least one further UV-absorber and/or hindered amine light stabilizer if only one of the components (I) and (II) is present with the proviso that component (c) is not a compound of formula (A)-(D) as defined in claim 1.
1. A composition comprising
(a) a polyether polyol, a polyester polyol or a polyurethane,
(b) a UV-absorber of formula (Ia) and a hindered amine light stabilizer of formula (II),
2-(2-hydroxy-3,5-bis-1,1-dimethylbenzyl)phenyl)-2H-benzotriazole, a phenolic antioxidant and a phosphite,
where the overall amount of component (b) is 0.5% to 2%, by weight, based on the weight of the composition and the weight ratio of compounds of formulae (Ia):(II) is from 3:1 to 1:3.
2. A composition according to claim 1 , further comprising
(c) a hindered amine light stabilizer of formula HA-1 to HA-11 or a UV-absorber of formula UV-5 to UV-8, where the overall amount of (b) and (c) is 0.5% to 2% by weight, based on the weight of the composition,
HA-11) 7-oxa-3,20-diazadispiro[5.1.11.2]heneicosan-21-one, 2,2,4,4-tetramethyl-20-(oxiranylmethyl)-, polymer with (chloromethyl)oxirane
3. A process for stabilizing a polyether polyol, a polyester polyol or a polyurethane against degradation by light, oxygen and/or heat, which process comprises incorporating therein
(b) a UV-absorber of formula (Ia) and a hindered amine light stabilizer of formula (II),
2-(2-hydroxy-3,5-bis-1,1-dimethylbenzyl)phenyl)-2H-benzotriazole, a phenolic antioxidant and a phosphite,
where the overall amount of component (b) is 0.5% to 2%, by weight, based on the weight of the resultant composition and the weight ratio of compounds of formulae (Ia): (II) is from 3:1 to 1:3.
4. A composition according to claim 1 ,
where the phenolic antioxidant is pentaerythritol tetrakis 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate and the phosphite is bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite.