Foam stabilizing additive and polyurethane foam prepared in the presence thereof
AssigneeThe Dow Chemical Company
InventorsRobert Baumann, Rajinder Sood
Life of this patent
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Abstract
This invention relates to a polyurethane foam stabilizing additive that comprises from about 10 to about 50 weight percent a hydrocarbon oil, and in from about 90 to about 50 weight percent a polyester polyol which is a solid at room temperature. Use of the additive in a polyurethane foaming process provides for improved dimensional stability of the resulting foam. The additive is especially of value when preparing water blown polyether polyol-based polyurethane foam useful, for example, in sealant applications.
Claims16
A process for preparing a rigid polyurethane foam by reacting an organic polyisocyanate with a polyahl, which is a liquid at room temperature, in the presence of a blowing agent and a foam stabilizing additive characterized in that the additive, present in an amount of from about 1 to about 10 parts by weight per 100 parts liquid polyahl, comprises, based on total weight of (a) and (b):
- (a) from about 10 to about 50 weight percent of a hydrocarbon oil;
- and
- (b) from about 90 to about 50 weight percent of a polyester polyol which has a melting point of from about 50.degree. C. to about 115.degree. C., and
- wherein the blowing agent consists essentially of water present in from about 3.5 to about 10 parts by weight per 100 parts of liquid polyahl.
A two component polyurethane foam-forming system which comprises:
- (a) an organic polyisocyanate;
- and
- (b) an isocyanate reactive composition containing a polyahl which is a liquid at room temperature, water present in from about 3.5 to about 10 parts per 100 parts by weight of liquid polyahl, from about 1 to about 10 parts per 100 parts by weight of liquid polyahl of a foam stabilizing additive that, based on total weight of (i) and (ii), contains:
- (i) from 10 to about 50 weight percent of a hydrocarbon oil;
- and
- (ii) from about 90 to 50 weight percent of a polyester polyol which has a melting point of from about 50.degree. C. to about 115.degree. C.
In a process for preparing a rigid polyurethane foam by reacting a polyisocyanate with a liquid polyahl which is a polyether polyol or polyamine in the presence of water the improvement comprising the presence of from about 2 to about 10 parts per 100 parts by weight of liquid polyahl of a foam stabilizing additive which consists, based on total weight of (a) and (b), of:
- (a) from 10 to about 50 weight percent of a hydrocarbon oil;
- and
- (b) from about 90 to 50 weight percent of a polyester polyol which has a melting point of from about 50.degree. C. to about 115.degree. C.
- wherein the resulting foam exhibits enhanced dimensional stability.
A process for preparing a rigid polyurethane foam by reacting a methylene-bridged polyphenyl polyisocyanate with one or more polyether polyols which has an average hydroxyl equivalent weight of from about 50 to about 700 in the presence of a blowing agent and a foam stabilizing additive characterized in that the additive, present in an amount of from about 1 to about 10 parts by weight per 100 parts of polyether polyol, comprises:
- (a) from about 10 to about 50 weight percent, based on total weight of (a) and (b), of a hydrocarbon oil;
- and
- (b) from about 90 to about 50 weight percent, based on total weight of (a) and (b), of a polyester polyol which has a melting point of from about 50.degree. C. to about 115.degree. C., and wherein the blowing agent, which is substantially free of a halogen-containing substance, consists essentially of water present in from about 3.5 to about 10 parts by weight per 100 parts of polyether polyol.
Dependencies are inferred from the claim text.