Ester alcohols and substituted carbamates thereof for minimizing deterioration of polyurethane foams
View Patent ↗A composition for making a polyurethane foam includes a non-fugitive tertiary amine urethane catalyst and an ester alcohol or substituted carbamate thereof. Foams prepared from the reaction of a polyol and an organic isocyanate in the presence of these ingredients show excellent resistance to deterioration of physical properties upon humid ageing.
1. A method of making a flexible molded polyurethane foam, the method comprising combining in a mold a flexible polyurethane foam reaction mixture comprising (i) an ester-free polyol component consisting of 0-100 wt % polyether polyol and 100-0 wt % graft and/or polyurea modified co-polyols, (ii) an organic polyisocyanate, (iii) a non-fugitive tertiary amine urethane catalyst having an isocyanate reactive group, and (iv) an ester alcohol or substituted carbamate thereof which is a
diacid ester diols or substituted carbamates according to formula (I)
wherein each R is independently H or substituted carbamoyl, each Z and each A is independently selected from divalent radicals, and n is a number having a value from 1 to 100;
wherein the ratio of equivalents of ester groups in the ester alcohol or substituted carbamate thereof to tertiary amine equivalents in the non-fugitive catalyst is in a range of 0.1:1 to 5:1 and the ratio of hydroxyl equivalents in the ester alcohol or substituted carbamate thereof to hydroxyl equivalents in the polyol component is greater than 0 and less than 1.5.
2. The method of claim 1 , wherein the polyol component comprises at least 50 wt % in total of one or more polyether polyols.
3. The method of claim 1 , wherein
a) each Z is independently selected from the group of divalent radicals consisting of (CH 2 ) m wherein m is an integer from 2 to 6, C 3 H 6 , CH 2 —CH(CH 3 )—CH 2 , CH 2 —CH(CH 3 ), CH 2 —CH(CH 2 —OR 1 ) wherein R 1 is C 1 -C 6 alkyl, and divalent radicals derived from any of diethylene glycol, triethylene glycol, polyethylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, ethylene glycol-propylene glycol copolymers, glycerol, phenols, 2-methyl-1,3-propanediol, and pentanetriol; and
b) each A is selected from the group consisting of CH═CH, CR 2 ═CH, CR 2 ═CR 2 , CH 2 , CHR 2 , C(R 2 ) 2 , C(R 2 ) 2 —C(R 2 ) 2 , CR 2 R 3 —CR 2 R 3 , (CH 2 ) m , and aromatic diradicals, wherein R 2 and R 3 are independently hydrogen, C 1 -C 6 alkyl groups, OH or halogen.
4. The method of claim 1 in which the foam reaction mixture further comprises one or more components selected from blowing agents, crosslinkers, additional urethane catalysts, and surfactants.
5. The method of claim 1 in which A is a divalent radical selected from C 10 H 6 ; C 6 H 4 ; CH 2 ; CH═CH; CH 2 CH 2 ; and (CH 2 ) 4 .
6. The method of claim 1 in which Z is C 3 H 6 .
7. The method of claim 1 in which n is 1-5.
8. The method of claim 1 in which n is 1-3.
9. The method of claim 1 in which the diacid ester diol is selected from the following compounds, and their positional isomers