US Patent 7951417 Bio-based adhesive material for roof shingles

An adhesive product and method of making the product replaces asphalt in the manufacture of roofing shingles. The method comprises steps of forming a mixture of oil comprising fatty acids and a powdered catalyst operable to catalyze the polymerization of the oil; maintaining the oil to powdered catalyst weight ratio in the mixture between 1 to 0.01 and 1 to 4.9; heating the mixture to a reaction temperature greater than 100 degrees Centigrade; maintaining the reaction temperature for at least five minutes; and, injecting air into the mixture while maintaining the reaction temperature. In making a roofing shingle, the method includes additional steps of: applying the heated mixture to a fiberglass mat sheet from an upstream roll to form a tacky coated strip; and, adding a layer of granules to the tacky coated strip. The adhesive material of this method comprises polymerized oil and the powdered catalyst.