Process for preparing polyurethane foam in the presence of a hydrocarbon blowing agent
AssigneeThe Dow Chemical Company
InventorAdrian J. Birch
Life of this patent
Estimating the term…
Abstract
Disclosed is a process for preparing a rigid, hydrocarbon blown, polyurethane foam by reacting a polyisocyanate with a polyol composition comprising a fatty oil. The fatty oil has a fatty acid content, especially a hydroxyl-substituted fatty acid, which enhances the miscibility of the hydrocarbon blowing agent. A preferred fatty oil is castor oil comprising as principle constituent the hydroxyl-substituted fatty acid, ricinoleic acid. Enhanced storage stability of a polyol composition containing hydrocarbon blowing agent in amounts required for production of low density foam is observed.
Claims15
A process for preparing a closed-celled polyurethane foam which comprises reacting, in the presence of a hydrocarbon blowing agent, a polyisocyanate with a polyol composition wherein the polyol composition comprises:
- i) a polyether or polyester polyol having a hydroxyl number value of from about 100 to about 1200;
- and
- ii) from about 5 to about 25 parts, per 100 parts by total weight of the polyol composition, of a fatty oil having a hydroxyl number of from about 100 to about 200.
A process for preparing a closed-celled polyurethane foam having a density of from about 10 to about 50 kg/m.sup.3 by reacting, in the presence of a hydrocarbon blowing agent, a polyisocyanate with a polyol composition wherein the polyol composition comprises:
- i) a polyol composition containing a polyether polyol having a hydroxyl number value of from about 100 to about 1200, and including from about 7 to about 15 parts, per 100 parts by total weight of the polyol composition, of a fatty oil being castor oil;
- in the presence of
- ii ) from about 2 to about 6 parts of water per 100 parts by weight of polyol composition;
- and
- iii) a hydrocarbon blowing agent being n-pentane, i-pentane, hexane, cyclopentane, methylcyclopentane, cyclohexane, methylcyclohexane or mixtures thereof, and
- wherein the polyisocyanate is present in an amount to provide for an isocyanate reaction index of from about 60 to about 300.
Dependencies are inferred from the claim text.