Patent ID: 6074469
Filing Date: 2000-06-13
Classification: C08K,C08L,C09D

Abstract:
A method of forming a paving asphalt composition comprising the steps of:heating an asphalt base stock at a temperature sufficient to form a liquid asphalt base stock;combining the liquid asphalt base stock with a heavy residuum of re-refined motor oil to form an asphalt mixture;combining the liquid asphalt base stock, the heavy residuum of re-refined motor oil, or the asphalt mixture with a chemical modifier selected from the group consisting of maleic anhydride, oxygen, sulfur, a strong mineral acid and a caustic compound to form a modified asphalt mixture;passing the modified asphalt mixture through a high shear mill to form a sheared asphalt mixture; andmixing the sheared asphalt mixture for a time sufficient to form a paving asphalt composition, wherein the paving asphalt composition has a dynamic shear greater than about 1 kPa at a first temperature and a direct tension greater than about 1% at a second temperature.