QC/T 944-2013Test method for polybrominated biphenyls (PBBs) and polybrominated diphenyl ethers (PBDEs) in automotive materials (English PDF)

3.1 Principle

Place the prepared sample in a sample chamber of an X-ray fluorescence spectrometer. Analyze the sample according to the selected test mode.

Determine whether the content of bromine in the sample is qualified according to the screening limits of different samples, and whether it is necessary to carry out accurate determination.

3.2 Reagents and materials

3.4 Sample preparation

3.4.1 Sample preparation principle

3.4.1.1 The sample used for the test must cover the measurement window of the spectrometer.

3.4.1.2 The irradiated surface of the sample should be representative of the sample as a whole.

3.4.1.3 Pay attention to pollution prevention during sample preparation

process.

3.4.2 Sample preparation method

3.6.2 Screening of bromine

In accordance with Requirements for Prohibited Substances on Automobiles of which the mass fractions of the limits of polybrominated biphenyls (PBBs) and polybrominated diphenyl ethers (PBDEs) are 0.1% (1000 mg/kg), the screening limits for bromine in automotive materials are shown in Table 1. Screen the bromine in automotive materials based on screening limits. There are two cases in results. Pass (P) - if the test results are less than the set minimum, the result shall be acceptable; Uncertain (X) - if the test results are greater than the set minimum, the result shall be uncertain and a further test shall be carried out in accordance with Method 2.

3.6.3 Report of test results

Take the arithmetic mean of the test results as report results, in milligrams/kilograms (mg/kg).

4.1 Principle

Samples are extracted with toluene as solvent. After the extracted volume to the appropriate volume, use Gas Chromatography-Mass Spectrometry (GC- MS) Full Scan Mode (SCAN) and select Ion monitoring mode (SIM) to qualitatively and quantitatively determine the polybrominated biphenyls and polybrominated diphenyl ethers in extracts. Then calculate their content in automotive materials.

4.2 Reagents and materials

4.2.1

Solvents. toluene, chromatography pure; or acetone, cyclohexane, n-, hexane, methanol, dichloromethane, isooctane, nonane, etc.

4.2.3 Standard stock solution

Respectively take the right amount of polybrominated biphenyls and polybrominated diphenyl ether standard sample (4.2.2). Use toluene (4.2.1) to prepare 1 µg/mL mixed standard stock solution.

4.2.9 Glass wool

4.2.10 Micro-liter syringe or automatic pipette

4.2.11 Liquid nitrogen. industrial grade

4.3 Apparatus and equipment

4.3.4 Grinding device. including cutting machine or scissors, grinder, grinding machine and other devices, mainly for sample crushing

4.3.1 Gas chromatography - mass spectrometry. equipped with mass

selective detector (MSD), of mass range (100-1000) amu.

4.3.2 Soxhlet extractor with condenser

4.3.3 Rotary evaporator

4.3.5 Balance. a sense of 0.0001 g

4.5 Analysis steps

4.5.1 Soxhlet extraction

4.5.1.1 Add 70 mL of toluene (4.2.1) into the Soxhlet extractor. Extract 2h to clean the Soxhlet extractor, discard the extract.

4.5.2 Determination

4.5.2.1 Refer to gas chromatography - mass spectrometry conditions

Gas chromatography-mass spectrometry parameters should be set to ensure that chromatographic determination of the measured components and other components can be effectively separated.

4.5.2.2 Calibration curve plotting. Different concentrations of calibrated

standard solution (4.2.5) are injected into the gas chromatography-mass spectrometer in turn. Take calibrated standard solution concentration as abscissa, calibrated standard solution of the peak area as the vertical coordinate to build up the calibration curve.

4.7.2 Recovery rate

The recovery rate of polybrominated biphenyls (PBBs) and polybrominated diphenyl ethers (PBDEs) in automotive materials is between 70% and 130%.

4.7.3 Precision

Under repeatability conditions, the absolute difference between the two independent test results obtained is not more than 20% of the arithmetic mean of the two measured values. It is premised that the ratio is not more than 5% of the case of 20% of the arithmetic mean of the two measured values.