SN/T 5272-2019Rubber and rubber products. Determination of 3,3'-dichloro-4,4'-diaminodiphenylmethane. Meteorological chromatography-mass spectrometry (English PDF)

Foreword

This standard was drafted in accordance with the rules given in GB/T 1.1-2009.

This standard was proposed and managed by the General Administration of Customs of the People's Republic of China.

Drafting organization of this standard. Fuzhou Customs of the People's Republic of China.

1 Scope

This standard specifies the gas chromatography-mass spectrometry method for the determination of 3,3'-dichloro-4,4'-diaminodiphenylmethane in rubber and rubber products.

This standard applies to the determination of 3,3'-dichloro-4,4'-diaminodiphenylmethane in rubber and rubber products.

The lower limit of determination in this standard is 20.0 mg/kg.

2 Method summary

The sample was ultrasonically extracted with ethyl acetate, the extract was centrifuged and filtered, and the filtrate was determined by gas chromatography-mass spectrometer and quantified by internal standard method.

3 Reagents and materials

3.1 Ethyl acetate. chromatographically pure.

3.2 3,3'-Dichloro-4,4'-Diaminodiphenylmethane (C13H12Cl2N2, CAS number. 101-14-4). Purity >= 98.8%.

3.3 Deuterated perylene (C20D12, CAS number. 1520-96-3). purity >= 99.0%.

3.4 Standard stock solution (1 g/L). accurately weigh 0.1 g (accurate to 0.1 mg) 3,3'-dichloro-4,4'-diaminodiphenylmethane (3.2) Dissolve the standard substance in a 100 mL volumetric flask with ethyl acetate (3.1) and dilute to the mark. Store it in a sealed and dark place at 0 °C ~ 4 °C.

It is valid for one month.

3.5 Internal standard solution (0.5 g/L). accurately weigh out 0.05 g deuterated perylene (3.3) in a 100 mL volumetric flask, and dissolve it with ethyl acetate (3.1) Solve and dilute to the mark. Store in a sealed and dark place at 0 °C ~ 4 °C. The validity period is one month.

3.6 Standard working solution. draw an appropriate amount of standard stock solution (3.4) and internal standard solution (3.5), and use a stepwise dilution method.

Ethyl acetate (3.1) is formulated into 3,3'-dichloro-4,4'-diaminodiphenylmethane with a concentration of 0 mg/L, 2 mg/L, 5 mg/L, 10 mg/L, A series of standard working solutions of 20 mg/L, 50 mg/L and the internal standard concentration of 20 mg/L.

4 Apparatus and equipment

4.1 Gas chromatography-mass spectrometer. equipped with EI source.

4.2 Analytical balance. Sensitivity 0.1 mg.

4.3 Ultrasonic oscillator. the power is not less than 220 W.

4.4 Centrifuge. the speed is not less than 2 500 r/min.

4.5 Pipette gun. 1 000 µL.

4.6 Pipette. 1 mL, 2 mL, 5 mL, 20 mL.

4.7 Plastic centrifuge tube with lid. 50 mL.

4.8 Needle organic filter. 0.45 µm.

4.9 Cutting tools. cutting knives, scissors, sharp knives or other suitable tools.

5 Sample preparation

Use the cutting tool (4.9) to make the sample into a sample of about 1 mm, and use it for the test after mixing.

6 Analysis steps

7 Result calculation

The calculation result is expressed as the arithmetic average of two independent measurement results obtained under repeatability conditions, and the result is kept to one decimal place.

8 Precision

Under repeatability conditions, the absolute difference between the two independent determination results is not more than 10% of the arithmetic mean; under repeatability conditions, the absolute difference between the results of the two laboratories is not more than 15% of the arithmetic mean.

Appendix A

(Informative appendix)