GB 31604.37-2016Food contact materials for export -- Polymers -- Determination of triethylamine and tributylamine in polycarbonate resin and its products -- Gas chromatography (English PDF)

3.1 Reagents

3.1.1 Dichloromethane (CH2Cl2).

3.1.2 Acetone (C3H6O).

3.2 Standard product

3.2.1 Triethylamine (C6H15N, CAS No.. 121-44-8). a standard substance with

a purity of >=99% or certified by the state and granted with a standard substance certificate.

3.2.2 Tributylamine (C12H27N, CAS No.. 102-82-9). a standard substance

with a purity of >=99% or certified by the state and granted with a standard substance certificate.

conical flask. After the addition, shake the bottle solution. Centrifuge 10 min.

Take the supernatant and evaporate to a concentration of nearly 1 mL.

Completely transfer the concentrate to a plugged centrifuge tube. Dilute with dichloromethane and set volume to 2.0 mL. Obtain the sample solution for the gas chromatography determination.

NOTE 1. The solution centrifugation can be performed in several times. The supernatant after centrifugation must be merged.

NOTE 2. If there is a small amount of turbidity in the sample solution, it can be filtered by a needle-type organic phase filter and then measured by gas chromatography.

5.3 Blank test

Except that the sample is not added, use the same analysis steps, reagents and dosage same as in 5.2 for parallel operation.

5.4 Gas chromatography reference conditions

5.4.1 Chromatographic column. ZB-5 quartz capillary column, column

length of 30m, inner diameter of 0.32mm, film thickness of 5µm, or the equivalent.

5.4.2 Column temperature. initial temperature of 40°C, hold 5min; then

increase at 20°C/min to 250°C for 5min.

5.4.3 Inlet temperature. 200°C.

5.4.4 Detector temperature. 250°C.

5.4.5 Carrier gas. nitrogen (purity >=99.999%), flow of 1.0 mL/min.

5.4.6 Detector hydrogen flow rate. 3 mL/min.

5.4.7 Detector air flow. 60 mL/min.

5.4.8 Injection volume. 1 µL.

5.4.9 Injection method. split-less injection.

5.5 Making of standard working curve

Inspect the standard working solution according to the chromatographic conditions listed in 5.4. Take the concentration of triethylamine and tributylamine (mg/L) in the standard working solution as the abscissa, the corresponding chromatographic peak area as the ordinate, perform the linear regression to draw the standard working curve.

5.6 Sample solution determination

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