SN/T 5259-2020 in English
VALIDDetermination of ultraviolet absorbers UV-320,UV-327,UV-328 and UV-350 in coatings-Gas chromatography-mass spectrometry method
- Issued on:2020-08-27
- Implemented on:2021-03-01
- File Format:PDF
- Delivery:Via email within 1~3 business days
$156.00
Introduction
Standard Technical Background and Scope of Application
SN/T 5259-2020 is a special testing standard formulated by the General Administration of Customs of my country for the control of UV absorbers in imported and exported coatings. This standard fills the gap in the detection method of benzotriazole UV absorbers in coatings, and is particularly suitable for the detection needs of water-based/solvent-based coatings by gas chromatography-mass spectrometry.
Analysis of core detection methods
| Key steps | Solvent-based coatings | Water-based coatings |
|---|---|---|
| Extraction solvent | n-hexane | Acetonitrile |
| Ultrasonic time | 20 minutes (control temperature ≤40℃) | |
| Purification method | Silica gel column purification (flow rate 2 seconds/drop) | |
Typical application case: UV-327 was found to exceed the standard (detection value 258mg/kg) in the inspection of a certain furniture coating for export. The separation by the DB-5 MS chromatographic column of this standard and the confirmation of the characteristic ion m/z 342 avoided the trade dispute caused by the migration of the UV absorber.
Key points for instrument parameter optimization
The standard recommended heating program adopts a two-step heating: initially 100℃ for 1min, then increase to 200℃ at 20℃/min for 1min, and then increase to 290℃ at 5℃/min for 5min. This condition ensures that the four targets are completely separated within 15min (resolution>1.5).
Quality control requirements
- Lower limit of determination: 10mg/kg (Signal-to-noise ratio S/N≥3)
- Precision control: Repeatability RSD≤5.5%, reproducibility RSD≤28.6%
- Recovery verification: 100-500μg spiked samples should be used for regular verification
Implementation suggestions
- During sample preparation, ensure that the coating film is completely dry (ventilation drying for 24h is recommended)
- For high viscosity samples, it is recommended to appropriately extend the ultrasonic time to 30 minutes
- Regularly replace the GC-MS injection port liner and the front end of the chromatographic column (every 200 injections)
Loading PDF document...
Error loading PDF. Please make sure the file is valid and try again.
We also recommend
-
SN 0283-1994 in English
\"Method for Inspection of Dichlorodipyridinol Residues in Exported Poultry Meat\"
1994-02-18 -
SN/T 0244-1994 in English
\"General Rules for Inspection and Certification of Imported Mechanical and Electrical Instruments\"
1993-08-01 -
SN/T 0568-2017 in English
Rules of inspection of canned low temperature ham for export
2017-11-07 -
SN/T 5233-2020 in English
Import and export textile material Test of moisture regain of raw cotton-Near infrared spectroscopy method
2020-08-27
