초록 ▼

A method for providing intercalated graphite flake with improved exfoliation characteristics, specifically, improved expansion pressure, is presented. The method includes treating graphite flakes with an oxidizing intercalant solution to provide intercalated graphite flakes; washing the intercalated

A method for providing intercalated graphite flake with improved exfoliation characteristics, specifically, improved expansion pressure, is presented. The method includes treating graphite flakes with an oxidizing intercalant solution to provide intercalated graphite flakes; washing the intercalated graphite flakes; and adding a surfactant to the washed graphite flakes. The invention also includes the intercalated graphite flakes thusly prepared.

대표청구항 ▼

1. A method for providing intercalated graphite flake with improved exfoliation characteristics, comprising: (i) treating graphite flakes with an oxidizing intercalant solution to provide intercalated graphite flakes; (ii) washing the intercalated graphite flakes; (iii) adding a surfactant to the wa

1. A method for providing intercalated graphite flake with improved exfoliation characteristics, comprising: (i) treating graphite flakes with an oxidizing intercalant solution to provide intercalated graphite flakes; (ii) washing the intercalated graphite flakes; (iii) adding a surfactant to the washed graphite flakes; and (iv) exposing the graphite flakes to an expansion aid applied prior to, during or immediately after treatment with the oxidizing intercalant solution, wherein said expansion aid is selected from the group consisting of carboxylic acids consisting of carbon, hydrogen, and oxygen atoms; alkyl esters; naphthoic acids; anthranilic acid; p-aminobenzoic acid; acetoacetoamidobenzoic acids; acetamidobenzoic acids; anhydrides of the aforementioned acids; and mixtures thereof. 2. The method of claim 1 wherein the surfactant comprises hexadecanol, lignins, glycols, organosilicones or mixtures thereof. 3. The method of claim 2 wherein the surfactant comprises sodium lignosulfonate. 4. The method of claim 2 wherein the surfactant comprises nonylphenol polyethylene glycol ether. 5. The method of claim 2 wherein the surfactant comprises polyalkyleneoxide modified polydimethylsiloxane. 6. The method of claim 1 wherein the surfactant is added to the washed graphite flakes at a level of about 0.25 to about 5 pph. 7. The method of claim 1 wherein the oxidizing intercalant solution comprises a mixture of nitric acid and sulfuric acid. 8. The method according to claim 1 wherein said intercalant solution comprises a mixture of sulfuric acid and an oxidizing agent, wherein said oxidizing agent comprises at least one of nitric acid, perchloric acid, chromic acid, potassium permanganate, hydrogen peroxide, iodic acids, or periodic acids. 9. The method of claim 1 wherein the expansion aid comprises an organic material sufficiently soluble in the oxidizing intercalant solution to achieve an enhanced expansion pressure. 10. The method of claim 1 wherein the expansion aid comprises a carboxylic acid. 11. The method according to claim 1 further comprising exfoliating said washed graphite flake after said adding said surfactant. 12. The method according to claim 11 wherein said exfoliating comprises heating said washed graphite flake to a temperature of at least about 150° C. 13. The method according to claim 1 wherein said carboxylic acids consisting of carbon, hydrogen, and oxygen atoms are selected from aliphatic, cycloaliphatic, straight chain, branched chain, saturated, unsaturated monocarboxylic acids, dicarboxylic acids or polycarboxylic acids. 14. The method according to claim 1 wherein said carboxylic acids consisting of carbon, hydrogen, and oxygen atoms are selected form formic acid, oxalic acid, fumaric acid, malonic acid, maleic acid, succinic acid, glutaric acid, adipic acid, 1,5-pentanedicarboxylic acid, 1,6-hexandedicarboxylic acid, 1,10-decanedicarboxylic acid, cyclohexane-1,4-dicarboxylic acid, phthalic acid, terephthalic acid, cyclohexane carboxylic acid, benzoic acid, naphthoic acid, anthranilic acid, p-aminobenzoic acid, salibylic acid, o-, m-and p-tolyly acids, methoxybenzoic acid, ethoxybenzoic acids, phenylacetic acid, hydroxybenzoic acid, citric acid, and mixtures thereof. 15. The method according to claim 1 wherein said exposing the graphite flakes to an expansion aid occurs prior to or during treatment with the oxidizing intercalant solution and said expansion aid further comprises an organic solvent to improve solubility of said expansion aid in said intercalant solution.