Claims
- 1. A scale and corrosion inhibiting composition, comprising: an amino thiol or disulfide compound of the structure:
- 2. The composition of claim 1 wherein the amino thiol or disulfide compound is selected from the group consisting of cysteine, cystine, cysteamine, cystamine, and salts thereof.
- 3. The composition of claim 1 wherein the acidic amino acid polymer is selected from the group consisting of polyaspartic acid, polyglutamic acid, and a block or random copolymer comprising:
a) at least one amino acid derived monomer selected from the group consisting of aspartic acid and glutamic acid, and b) one or more co-monomers selected from the group consisting of polybasic carboxylic acids and anhydrides, fatty acids, polybasic hydroxycarboxylic acids, monobasic polyhydroxycarboxylic acids, amines, di and triamines, polyamines, hydroxyl-substituted aliphatic amines, carbohydrates, sugar carboxylic acids, amino acids, non-protein forming aminocarboxylic acids, lactams, lactones, diols, triols, polyols, unsaturated dicarboxylic and tricarboxylic acids, unsaturated monocarboxylic acids, derivatized aspartic acid residues, and derivatized glutamic acid residues; and wherein the sum of the aspartic and/or glutamic acid residues is at least about 20% of the total number of residues in the polymer.
- 4. The composition of claim 1 wherein the inhibitor compound and acidic amino acid polymer are present in the composition in a weight ratio of inhibitor compound-to-acidic amino acid polymer in the range of about 1:1000 to about 1000:1, respectively.
- 5. The composition of claim 1 wherein the acidic amino acid polymer is a homopolymer or copolymer of an amino acid selected from the group consisting of aspartic acid, glutamic acid, and a salt thereof.
- 6. The composition of claim 1 wherein the acidic amino acid polymer comprises polyaspartic acid or a salt thereof.
- 7. The composition of claim 1 wherein the acidic amino acid polymer has a molecular weight in the range of about 500 to about 100,000.
- 8. The composition of claim 1 wherein the acidic amino acid polymer has a molecular weight in the range of about 1,000 to about 20,000.
- 9. The composition of claim 1 which further comprises additives selected from the group consisting of a corrosion inhibitor, a biocide, a surfactant, a scale inhibitor, and mixtures thereof.
- 10. A corrosion and scale inhibiting composition comprising:
a) an amino thiol or disulfide compound selected from the group consisting of: cysteine, cystine, cysteamine, cystamine and salts thereof; and b) polyaspartic acid or a salt thereof; wherein the ratio of the amino thiol or disulfide compound to the polyaspartic acid or salt thereof is in the range of about 1:1000 to about 1:10, respectively, on a weight basis.
- 11. The composition of claim 10 wherein the polyaspartic acid or salt thereof has a molecular weight in the range of about 1,000 to about 20,000 daltons.
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of co-pending U.S. patent application Ser. No. 09/325,985, filed on Jun. 4, 1999, now U.S. Pat. No. 6,447,717.
Continuations (1)
|
Number |
Date |
Country |
Parent |
09325985 |
Jun 1999 |
US |
Child |
10237921 |
Sep 2002 |
US |