GB/T 15045-2013Fatty alkyl dimethyl tertiary amines (English PDF)

3.1 Structural formula CH3 N -R (R=CnH2n+1, n=even number between 8 and 24) CH3

3.2 Categories and codes Fatty alkyl dimethyl tertiary amines can be divided into 12 categories according to the fatty alkyl carbon atom numbers and main constituents. Categories and codes are as follows: Tertiary amine

5.3.2.4 Standard solution of HCl- isopropyl alcohol-ethylene glycol, c =

0.15 mol/L. Add prepared HCl into the mixed solution of ethylene glycol and isopropyl alcohol (1.1, volume fraction); shake well; then conduct calibration in accordance with the provisions of QB/T 2739. The standard solution shall be sealed and stored in the refrigerator at about 10°C to avoid volatilization of the solvents due to high temperature. Before use, the standard solution shall be placed in room temperature to let it recover to the room temperature; the validity is 1 month.

5.3.3 Instruments

5.3.3.1 Titration vessel or beaker, 100 mL.

5.3.3.2 Graduated cylinder, 50mL.

5.3.3.3 Acidometer.

5.3.4 Test procedures Weigh

0.2 g~

0.3 g (less low-molecular-weight sample and more high-molecular-weight sample) of evenly melted and mixed sample (precision. 0.0001g); add into a 100 mL titration vessel or beaker; slowly add in 10 mL of acetic anhydride (if there is any solid in the sample, it shall be heated in hot water till melted); shake well; let the solution stay in room temperature for 15 min; then add in 50 mL of isopropyl alcohol solution; put it on the acidometer; conduct potentiometric titration by using standard solution of HCl- isopropyl alcohol-ethylene glycol (5.3.2.4) until the potential jumps to the maximum value; then write down the volume of standard solution of HCl- isopropyl alcohol-ethylene glycol that has been used in the titration (V1). Weigh another sample with an equivalent mass; without adding acetic anhydride, repeat the above test steps; write down the volume of standard solution of HCl- isopropyl alcohol-ethylene glycol that has been used in the titration (V2). titration, unit. mL; c- The molar concentration of standard solution of NaOH-ethyl alcohol, unit. mol/L; M- The molar mass of fatty alkyl dimethyl tertiary amine, unit. g/mol; m3 - The mass of the sample, unit. g. The arithmetic mean value of two parallel determination results shall be used to express the determination results, correcting to one decimal place.

5.4.6 Degree of precision The absolute difference of two independent tests' results obtained under the same conditions shall not be more than 0.03%, which is on the premise that the probability with absolute difference more than 0.03% does not exceed 5%.

5.5 Main constituents, free alcohols and average relative molecular mass

5.5.1 Principle Separate the sample with chromatographic column; calculate the average relative molecular mass, main constituent content and free alcohol content through chromatogram peak area.

5.5.2.1 Absolute ethyl alcohol

5.5.2.2 Reference sample. fatty alkyl dimethyl tertiary amine and fatty alcohol with known chain length, taking the sample with known constituents as the reference sample to determine the performance of the chromatographic instrument.

5.5.2.3 Carrier gas, nitrogen, fuel gas, hydrogen, oxidant gas, air.

5.5.3 Instruments

5.5.3.1 Chromatographic instrument, with flame ionization detector and programmed temperature.

5.5.3.2 Chromatographic column. HP-5 can be used for analyzing C8-C18, specification. 30 m×

0.32 mm×0.5µm or equivalence, Rtx-200 can be used for analyzing C18/22 and C22, specification. 30 m×

0.53 mm×0.5µm or equivalence.

5.5.3.3 Chromatographic processor or chromatographic work station.

5.5.4 Chromatographic conditions The typical reference conditions for chromatographic analysis are as follows; necessary

5.5.7 Degree of precision

5.5.7.1 The average relative molecular mass of fatty alkyl dimethyl tertiary amine The absolute difference of two independent tests' results obtained under the same conditions shall not be more than 1, which is on the premise that the probability with absolute difference more than 1 does not exceed 5%.

5.5.7.2 Free alcohols The absolute difference of two independent tests' results obtained under the same conditions shall not be more than 0.05%, which is on the premise that the probability with absolute difference more than 0.05% does not exceed 5%.

5.5.7.3 Main constituents The absolute difference of two independent tests' results obtained under the same conditions shall not be more than 0.7%, which is on the premise that the probability with absolute difference more than 0.7% does not exceed 5%.

6.1 Inspection classification

6.1.1 Delivery inspection The items that shall take delivery inspection include appearance, tertiary amine content, total amine value, primary and secondary amine and free alcohols as specified in Chapter 4.

6.1.2 Type inspection The items that shall take type inspection include all the items specified in Chapter 4. Type inspection shall also be conducted under the following conditions.