Quebracho-modified bitumen compositions, method of manufacture and use
AssigneeSaramco, Inc.
InventorsMark W. Shuey, Robert S. Custer
Life of this patent
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Abstract
The addition of from about 0.1 to about 25 parts by weight of quebracho per 100 parts of bitumens (particularly asphalt), coal tar, or other high boiling tars containing mixtures of aliphatic and aromatic hydrocarbons modifies the characteristics of the treated product to enhance its performance as hot-melt adhesives, coatings, sealants, roof-coatings, and road-coatings as compared to the base bitumen. The improved characteristics obtained by the addition of quebracho include: increased softening point, lower penetration number, and higher viscosity. The quebracho may be mixed directly with the tars or put into a water solution, using sodium hydroxide if necessary, and then added to hot tars with the water being driven off.
Claims17
A modified bitumen composition, comprising:
- a) at least 0.1 percent by dry weight quebracho;
- b) 100 parts by weight bitumen;
- and
- c) said quebracho is intimately dispersed in said bitumen to provide a continuous phase of quebracho-modified bitumen having increased softening temperature, increased hardness, and increased viscosity.
A method of making a modified bitumen composition comprising in operative order the steps of:
- a) heating a bitumen to above about its softening point to lower its viscosity to permit mechanical mixing and agitation of the bitumen;
- b) adding quebracho to said bitumen at the rate of 0.1 parts by dry weight to 25 parts by dry weight or more per 100 parts by weight of said bitumen;
- and
- c) mixing said quebracho with said bitumen to distribute said quebracho evenly in said bitumen to form a modified bitumen composition having increased softening temperature, increased hardness, and increased viscosity.
A method of using a modified bitumen comprising in operative order the steps of:
- a) providing a quebracho-modified bitumen;
- b) maintaining the viscosity of said modified bitumen low enough to be spreadable;
- and
- c) applying said modified bitumen to the surface to be treated.
Dependencies are inferred from the claim text.