Patent ID: 8828267

Claim:
A composition, comprising: a) an epoxy resin; and b) a mixture comprising 7 isomers of 2,4-diamino-1-methylcyclohexane and 2,6-diamino-1-methylcyclohexane in a ratio of 75 to 95% by weight of 2,4-diamino-1-methylcyclohexane to 5 to 25% by weight of 2,6-diamino-1-methylcyclohexane, wherein: GC area percentages of the 7 isomers, in order of ascending retention time, are determined by a gas chromatography method to be in a range from 4.0 to 49.0% for a peak 1, in a range from 0.3 to 9.0% for a peak 2, in a range from 9.0 to 19.0% for a peak 3, in a range from 11.0 to 30.0% for a peak 4, in a range from 3.0 to 10.0% for a peak 5, in a range from 8.0 to 40.0% for a peak 6, and in a range from 1.0 to 10.0% for a peak 7, where the sum of the GC area percentages based on the amount of the 2,4-diamino-methylcyclohexane and the 2,6-diaminomethylcyclohexane totals 100%; the composition excludes a mixture comprising 7 isomers of 2,4-diamino-1-methyl-cyclohexane and 2,6-diamino-1-methylcyclohexane in a ratio of 75 to 95% by weight of 2,4-diamino-1-methyl-cyclohexane to 5 to 25% by weight of 2,6-diamino-1-methyl-cyclohexane, wherein GC area percentages of which, in order of ascending retention time, are determined by the gas chromatography method to be in a range from 15.6 to 16.6% for a first peak, in a range from 0.1 to 0.4% for a second peak, in a range from 32.2 to 33.2% for a third peak, in a range from 23.5 to 24.5% for a fourth peak, in a range from 4.1 to 5.1% for a fifth peak, in a range from 18.1 to 19.1% for a sixth peak, and in a range from 2.6 to 3.6% for a seventh peak, where the sum of the GC area percentages based on the amount of 2,4-diamino-methylcyclohexane and 2,6-diaminomethylcyclohexane totals 100%; the gas chromatography method comprises distilling a mixture comprising isomers and collecting a distilled mixture, dissolving the distilled mixture into tetrahydrofuran to form an isomeric solution, injecting the isomeric solution into a column of a gas chromatograph, and detecting peaks with a flame ionization detector at 280° C., wherein: the column is 30 m in length, has an internal diameter of 0.25 mm, and has a film thickness of 0.5 μm; the column is operated with helium as a mobile phase and comprises a stationary phase comprising 35% by weight of diphenyl and 65% by weight of dimethylpolysiloxane; the column is operated at temperatures in a range from 100 to 250° C. during the method; a rate of helium enrichment is 40 ml/min during the method; the method is conducted with a split ratio of 1 to 40; the injecting occurs at an injection temperature of 100° C., an inlet pressure of 1 bar, and at a heating rate of 1° C./min until a temperature of 120° C. is attained; after a temperature of 120° C. is maintained the heating rate is increased to 5° C./min and is maintained at 5° C./min until a final temperature of 250° C. is reached; and after the final temperature of 250° C. is reached the final temperature is maintained for 10 min.