Filled polyurethane composites and methods of making same

A method of preparing a rigid composite material comprising:

• mixing (1) an isocyanate selected from the group consisting of diisocyanates, polyisocyanates and mixtures thereof, (2) at least two polyols, the at least two polyols comprising (i) a high hydroxyl number polyol selected from the group consisting of polyether polyols and polyester polyols, the high hydroxyl number polyol having a hydroxyl number greater than 250 and having 75% or greater primary hydroxyl groups, wherein the high hydroxyl number polyol includes an aromatic polyester polyol and wherein the high hydroxyl number polyol comprises from about 1% to about 25% by weight of the total polyol content used to form the polyurethane, and (ii) a low hydroxyl number polyol selected from the group consisting of polyether polyols and polyester polyols, the low hydroxyl number polyol having a hydroxyl number of 250 or lower, (3) coal ash, and (4) a catalyst;
• and
• allowing the isocyanate and the at least two polyols to react in the presence of the coal ash and catalyst to form the composite material,
• wherein the amount of coal ash added in the mixing step comprises from about 40% to about 90% by weight of the composite material,
• wherein the composite material has a density of 5 lb/ft3 or greater.

A method of preparing a rigid composite material comprising:

• mixing (1) an isocyanate selected from the group consisting of diisocyanates, polyisocyanates and mixtures thereof, (2) at least two polyols, the at least two polyols comprising (i) a high hydroxyl number polyol selected from the group consisting of polyether polyols and polyester polyols, the high hydroxyl number polyol having a hydroxyl number greater than 250 and having 75% or greater primary hydroxyl groups, wherein the high hydroxyl number polyol comprises an aromatic polyester polyol and the high hydroxyl number polyol comprises from about 1% to about 25% by weight of the total polyol content used to form the polyurethane, and (ii) a low hydroxyl number polyol selected from the group consisting of polyether polyols and polyester polyols, the low hydroxyl number polyol having a hydroxyl number of 250 or lower, (3) coal ash, and (4) a catalyst;
• and
• allowing the isocyanate and the at least two polyols to react in the presence of the coal ash and catalyst to form the composite material,
• wherein the high hydroxyl number polyol, when replacing the polyol used in the standard polyurethane formulation of the Brookfield Viscosity Test, produces a Brookfield viscosity of over 50,000 cP in less than 225 seconds,
• wherein the amount of coal ash added in the mixing step comprises from about 40% to about 90% by weight of the composite material, and
• wherein the composite material has a density of 5 lb/ft3 or greater.