GB/T 25787-20104，4’-Sulfonyldiphenol (Bisphenol-S) (English PDF)

5.1 General provisions

Unless otherwise specified, only analytically pure reagents and grade III water as specified in GB/T 6682 are used. The judgment of the inspection results is carried out according to the comparison method of rounded-off value of clause 4.3.3 in GB/T 8170-2008.

5.2 Assessment of appearance

Visual assessment is performed in natural light.

5.3 Determination of the initial melting point of dry products

It is performed according to the provisions of GB/T 2384-2006. The specimen is determined after drying in accordance with clause 5.5 of this standard.

The difference between the results of the two parallel determinations shall be not more than 0.1 °C. Take the arithmetic mean as the determination result.

5.4 Purity of 4,4'-Sulfonyldiphenol and content of 2,4-Bisphenol S

5.4.1 Method summary

High-performance reversed-phase liquid chromatography (HPLC) is used to separate 4,4'-sulfonyldiphenol and its components on octadecyl bonded stationary phase by the use of acetonitrile, water and glacial acetic acid as mobile phases. It is tested by the ultrasonic detector. The peak area normalization is used to determine the purity of 4,4'-Sulfonyldiphenol and content of 2,4-Bisphenol S.

5.4.2 Instrumentation

a) Liquid chromatograph. infusion pump - flow range (0.1 ~ 5.0) mL/min, the flow stability in this range is ± 1%;

Detector - Multi-wavelength ultraviolet spectroscopic detector or Weigh 3 g of sample, the drying temperature is 105 °C ~ 110 °C. The drying time is 4 h, the rest is carried out according to the provisions of clause 3.2 of GB/T 2386-2006. The allowable deviation is 0.05% (mass fraction).

5.6 Determination of ash content

It is carried out according to the provisions of GB/T 21876-2008, the temperature is 650 °C ± 25 °C, the sample amount is 10 g. The allowable deviation is 0.05% (mass fraction).

5.7 Determination of iron ion content

5.7.1 Method summary

Use the ascorbic acid to reduce the ferric ions in the specimen to divalent iron ions. At pH = 2 ~ 9, the divalent iron ions can react with 1,10-phenanthroline to form an orange-red complex. At the maximum absorption wavelength (510 nm) of the spectrophotometer, determine its absorbance; or otherwise perform visual comparison with the standard iron color scale.

5.7.2 Determination procedures

The specimen after ashing according to 5.6 of this standard is dissolved by 4 mL (1.9) of nitric acid solution, then it is determined according to the provisions of GB/T 3049-2006.

5.8 Determination of chromaticity

It is carried out according to the provisions of GB/T 605. Sample solvent. methanol, sample colorimetric concentration. 100 g/L, colorimetric tube. 25 mL. Error range. ±5 chromaticity number.

6.1 Classification of inspection

All items as specified in Table 1 of clause 3 of this standard are exit-factory inspection items.

6.2 Exit-factory inspection

4,4'-Sulfonyldiphenol shall pass the inspection by the quality inspection department of the manufacturer, be attached with the certificate of conformity, before exit-factory. The manufacturer shall ensure that all manufactured 4,4'- […]