Polyurethane foam scorch inhibitor
View Patent ↗A scorch inhibitor composition for polyurethane foams is composed of (a) one or more derivatized phenolic compounds in an amount of about 60-80% by weight; (b) one or more aromatic amines in the form of a liquid in an amount of about 15-35% by weight; (c) an alkyl-substituted hydroquinone in an amount of about 4-8% by weight, and (d) phenothiazine at 0 to about 1.0% by weight.
1. A polyurethane foam composition comprising polyol and a scorch inhibitor composition at about 0.10 to 0.75 parts per 100 parts polyol, the scorch inhibitor composition comprising:
(a) one or more derivatized phenolic compounds in an amount of about 60-80% by weight;
(b) one or more aromatic amines in the form of a liquid in an amount of about 15-35% by weight;
(c) an alkyl-substituted hydroquinone in an amount of about 4-8% by weight, selected from 2,5-di-tert-amyl-hydroquinone and di-tert-butyl-hydroquinone; and
(d) phenothiazine at 0 to about 1.0% by weight.
2. The composition of claim 1 , wherein the derivatized phenolic compound is selected from the group consisting of tetrakis[methylene(3,5-di-tert-butyl-4-hydroxyhydrocinnamate)]methane; iso-octyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate; isotridecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate; octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate; 2,6 di-tert-butyl-4-nonyl phenol; 1,2-bis(3,5-di-tert-butyl-4-hydroxyhydrocinnamoyl)hydrazine; 2,2′-thiodiethylene bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate; a (2,6-di-tert-butyl) phenol substituted at the 4 position with an aliphatic, aromatic or aliphatic-aromatic moiety, optionally possessing combinations of hetero atoms O, N, S, and P; and mixtures thereof.
3. The composition of claim 2 , wherein the derivatized phenolic compound comprises one or more in combination of (i) tetrakis[methylene(3,5-di-tert-butyl-4-hydroxyhydrocinnamate)]methane; (ii) iso-octyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate; and (iii) isotridecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate.
4. The composition of claim 1 , wherein the aromatic amine is one or both of (a) a reaction product of diisobutylene and diphenylamine and (b) 4,4′-bis(.alpha.,.alpha.-dimethylbenzyl)diphenyl amine).
5. The composition of claim 1 , wherein the alkyl-substituted hydroquinone is 2,5-di-tert-amyl-hydroquinone.
6. The composition of claim 1 , wherein
(a) is one or more of tetrakis[methylene(3,5-di-tert-butyl-4-hydroxyhydrocinnamate)]methane; iso-octyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate; and isotridecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate;
(b) is a reaction product of diisobutylene and diphenylamine;
(c) is 2,5-di-tert-amyl-hydroquinone; and
(d) phenothiazine is present.
7. The composition of claim 1 , wherein the scorch inhibitor composition is present at about 0.3 to 0.6 parts per 100 parts polyol.