Polyurethane foam useful for insulated containers

Claim 2

A hydroxyl component for the formation of polyurethane foams used in insulated containers wherein the foam shows improved resistance to cracking under cold conditions which consists essentially of a. from 20 to 70% wt, total, of one or more diols having m ether linkages, where m is 0 or 1, and having a molecular weight of at most 250, b. from 30 to 80% wt, total, of one or more polyethers of propylene oxide having n hydroxyl groups per molecule, where n is 2 or 3; and c. from 0 to 12% wt, total, of one or more amino-alcohols having three active hydrogen atoms; wherein all percentages are based on the combined weight of components (a) and (b), and said hydroxyl component has a number average functionality in the range of from about 1.8 to about 2.7 and a reactive group content in the range of from about 6 to about 11.

Claim 3

The hydroxyl component of claim 1 wherein (b) is a polypropylene glycol having a molecular weight range of 500-1350.

Claim 4

The hydroxyl component of claim 2 wherein (a) is dipropylene glycol, (b) is polypropylene glycol having a molecular weight of about 1050 and (c) is diethanolamine.

Claim 5

A hydroxyl component for the formation of polyurethane foams used in insulated containers wherein the foam shows improved resistance to cracking under cold conditions, which consists essentially of: a. from 3 to 35% wt, total, of one or more diols having m ether linkages, where m is 0 or 1, and having a molecular weight of at most 250, b. from 2 to 75% wt of a polypropylene glycol having a molecular weight in the range of 500-1350, c. from 0 to 12%, wt, total, of one or more amino-alcohols having three active hydrogen atoms; and d. from 20 to 70 wt % of a polyether of propylene oxide having 3 hydroxyl groups and having a molecular weight of at least 200; wherein all percentages are based on the combined weight of components (a), (b) and (d), said hydroxyl component having a number average functionality in the range of from about 1.8 to about 2.7 and a reactive group content in the range of from about 6 to about 11.

Claim 6

A hydroxyl component for the formation of polyurethane foams used in insulated containers wherein the foam shows improved resistance to cracking under cold conditions, which consists essentially of: a. from 3 to 35% wt, total, of one or more diols having m ether linkages, where m is 0 or 1, and having a molecular weight of at most 250, b. from 2 to 75% wt of a polypropylene glycol having a molecular weight in the range of 500-1350, c. from 0 to 12%, wt, total, of one or more amino-alcohols having three active hydrogen atoms; and d. from 20 to 70 wt % of a polyether of propylene oxide having 3 hydroxyl groups and having a molecular weight of at least 200; wherein all percentages are based on the combined weight of components (a), (b) and (d), said hydroxyl component having a number average functionality in the range of from about 1.8 to about 2.7 and a reactive group content in the range of from about 6 to about 11.

Claim 7

The hydroxyl component of claim 4 where (a) is dipropylene glycol, (b) is a polypropylene glycol of a molecular weight of about 1050 (c) is diisopropanolamine and (d) is a polyether of propylene oxide having a molecular weight of about 300.

Claim 8

An improved process for the formation of polyurethane foam showing improved resistance to cracking under cold conditions which comprises reacting, under foam forming conditions, a reaction mixture comprising an organic polyisocyanate component and a hydroxyl component consisting essentially of a. from 20 to 70% wt, total, of one or more diols having m ether linkages, where m is 0 or 1, and having a molecular weight of at most 250, b. from 30 to 80% wt, total, of one or more polyethers of propylene oxide having n hydroxyl groups per molecule, where n is 2 or 3; and c. from 0 to 12% wt, total, of one or more amino-alcohols having three active hydrogen atoms; wherein all percentages are based on the combined weight of components (a) and (b), and said reaction mixture has a number average functionality in the range from about 1.8 to about 2.7 and a reactive group content in the range of from about 6 to about 11.

Claim 9

An improved process for the formation of polyurethane foam showing improved resistance to cracking under cold conditions which comprises reacting, under foam forming conditions, a reaction mixture comprising an organic polyisocyanate component and a hydroxyl component consisting essentially of a. from 20 to 70% wt, total, of one or more diols having m ether linkages, where m is 0 or 1, and having a molecular weight of at most 250, b. from 30 to 80% wt, total, of one or more polyethers of propylene oxide having n hydroxyl groups per molecule, where n is 2 or 3; and c. from 0 to 12% wt, total, of one or more amino-alcohols having three active hydrogen atoms; wherein all percentages are based on the combined weight of components (a) and (b), and said reaction mixture has a number average functionality in the range from about 1.8 to about 2.7 and a reactive group content in the range of from about 6 to about 11.

Claim 10

The improved process of claim 6 where the polyisocyanate component is a mixture of diphenyl-4,4'-diisocyanate and diphenyl-2,4'-diisocyanate.

Claim 11

The improved process of claim 7 where the number average functionality is in the range of from about 2.0 to about 2.6.

Claim 12

The improved process of claim 8 where the reactive group content is in the range of from about 7 to about 10.

Claim 13

In a process for the preparation of insulated containers for storage and/or transport of cold liquids which comprise an outer rigid surface and an inner polyurethane foam layer or layers, optionally containing barriers composed of glass fiber and epoxy resin impregnated in the polyurethane, the improvement which comprises employing as the precursor of the polyurethane foam layer or layers a reaction mixture comprising a polyisocyanate component and a hydroxyl component consisting essentially of a. from 20 to 70% wt, total, of one or more diols having m ether linkages, where m is 0 or 1, and having a molecular weight of at most 250, b. from 30 to 80% wt, total, of one or more polyethers of propylene oxide having n hydroxyl groups per molecule, where n is 2 or 3 and c. from 0 to 12% wt, total, of one or more amino-alcohols having three active hydrogen atoms; wherein all percentages are based on the combined weight of components (a) and (b), and said reaction mixture has a number average functionality in the range from about 1.8 to about 2.7 and a reactive group content in the range of from about 6 to about 11.

Claim 14

In a process for the preparation of insulated containers for storage and/or transport of cold liquids which comprise an outer rigid surface and an inner polyurethane foam layer or layers, optionally containing barriers composed of glass fiber and epoxy resin impregnated in the polyurethane, the improvement which comprises employing as the precursor of the polyurethane foam layer or layers a reaction mixture comprising a polyisocyanate component and a hydroxyl component consisting essentially of a. from 20 to 70% wt, total, of one or more diols having m ether linkages, where m is 0 or 1, and having a molecular weight of at most 250, b. from 30 to 80% wt, total, of one or more polyethers of propylene oxide having n hydroxyl groups per molecule, where n is 2 or 3 and c. from 0 to 12% wt, total, of one or more amino-alcohols having three active hydrogen atoms; wherein all percentages are based on the combined weight of components (a) and (b), and said reaction mixture has a number average functionality in the range from about 1.8 to about 2.7 and a reactive group content in the range of from about 6 to about 11.