Abstract: The invention is directed to methods of preparing compositions used to manufacture polyurethane foams. The invention provides methods for making compositions used to make polyurethane foams that include amine catalysts, but formulated such that catalytic potency is not diminished over time before the forming of a foam.

Abstract: The invention is directed to polyurethane foams which are flotation resistant with sufficient strength and density to provide stability and inhibit erosion at pipeline trench sites, and other uses, wherein at least 50% of the foam is open cell and has a density of approximately 1.3 lbs/ft3 to 3.5 lbs/ft3.

Abstract: The invention is directed to methods for supporting trench pipes with polyurethane foams which are flotation resistant with sufficient strength and density to provide stability and inhibit erosion at pipeline trench sites, and other uses, wherein at least 50% of the foam is open cell and has a density of approximately 1.3 lbs/ft3 to 3.5 lbs/ft3. The invention also provides methods for making compositions used to make polyurethane foams that exhibit such characteristics.

Abstract: The invention is directed to polyurethane foams which are flotation resistant with sufficient strength and density to provide stability and inhibit erosion at pipeline trench sites, and other uses, wherein at least 50% of the foam is open cell and has a density of approximately 1.3 lbs/ft3 to 3.5 lbs/ft3.

Abstract: A method for producing a rigid, closed-cell polyurethane foam having a free-rise density of from about 1.3 lbs/ft.3 to about 4 lbs/ft.3 and exhibiting a shrinkage of less than 10%, comprises mixing together an isocyanate, at least one alkyl alkanoate blowing agent and at least one polyol having a hydroxyl number of from about 150 to about 800 and being selected from the group consisting of polyalkoxylated amines, polyalkoxylated ethers, and polyester polyols, to form a reaction mixture that is curable to produce such foam.

Abstract: A method for producing a rigid, closed-cell polyurethane foam having a free-rise density of from about 1.3 lbs./ft.3 to about 4 lbs./ft.3 and exhibiting a shrinkage of less than 10%, comprises mixing together an isocyanate, a methyl formate blowing agent and at least one polyol having a hydroxyl number of from about 150 to about 800 and being selected from the group consisting of polyalkoxylated amines, polyalkoxylated ethers, and polyester polyols, to form a reaction mixture that is curable to produce such foam.

Abstract: A method for producing a rigid, closed-cell polyurethane foam having a free-rise density of from about 1.3 lbs./ft.3 to about 4 lbs./ft.3 and exhibiting a shrinkage of less than 10%, comprises mixing together an isocyanate, a methyl formate blowing agent and at least one polyol having a hydroxyl number of from about 150 to about 800 and being selected from the group consisting of polyalkoxylated amines, polyalkoxylated ethers, and polyester polyols, to form a reaction mixture that is curable to produce such foam.

Abstract: A method for preparation of rigid foam disclosed The method comprises mixing at least two components to form a reaction mixture. The reaction mixture comprises isocyanate, up to about 20% by weight CHClF.sub.2, up to about 2% by weight of water, and a combination of polyols having an overage OH number of from about 300 to about 500 and comprising polyalkoxylated glycerin having an OH number of from about 200 to about 300 and in which the alkoxy groups each have from two to about three carbon atoms. Related methods and compositions are also disclosed.

Abstract: A method for preparation of rigid foam disclosed. The method comprises mixing at least two components to form a reaction mixture. The reaction mixture comprises isocyanate, up to about 20% by weight CHClF.sub.2, up to about 2% by weight of water, and a combination of polyols having an average OH number of from about 300 to about 500 and comprising polyalkoxylated glycerin having an OH number of from about 200 to about 300 and in which the alkoxy groups each have from two to about three carbon atoms. Related methods and compositions are also disclosed.

Abstract: A method for preparation of rigid foam disclosed. The method comprises mixing at least two components to form a reaction mixture. The reaction mixture comprises isocyanate, up to about 20% by weight CHClF.sub.2, up to about 2% by weight of water, and a combination of polyols having an average OH number of from about 300 to about 500 and comprising polyalkoxylated glycerin having an OH number of from about 200 to about 300 and in which the alkoxy groups each have from two to about three carbon atoms. Related methods and compositions are also disclosed.

Abstract: Dispensing gun for mixing and dispensing reactable fluent materials. A cylinder is slidable within a bore in response to a piston sliding within the cylinder. When the cylinder moves away from a discharge opening, orifices in the wall of the cylinder become aligned with supply passages in the bore allowing the reactable fluent materials to mix in the cylinder and be dispensed from the discharge opening. The cylinder, piston and orifices are cleaned by a cleaning solvent at the end of each dispensing operation. Movement of the piston towards the discharge opening draws the cleaning solvent through the orifices into the interior of the cylinder. The dispensing gun is particularly useful for mixing organic resins and polyisocyanates to dispense polyurethane foam.