GB/T 2385-2007General method for the determination of crystallizing point dye intermediates (English PDF)

Foreword

This revised standard adopts ISO 1392. 1977 "Determination of crystallizing point --- General Methods." this standard and ISO 1392. 1977 differences are as follows.

--- Standard format editorial changes;

--- This standard applies to the determination within the range of -10 °C ~ 150 °C dye intermediates crystallization point, the scope of ISO 1392 is Determination of -50 °C ~ 250 °C crystallization point substance (in this standard in Chapter 1; ISO 1392. Chapter 1, 1977);

--- This standard specifies the use Dewar, beakers used as the cooling bath and a hot tub, ISO 1392. 1977 using Dewar and thermal bath (this standard 6.1.7 and 6.1.8,6.1.9; ISO 1392. 1977 of 4.5,4.6,4.7);

--- Coolant provisions of this standard is ice, ice saline, glycerol, water and air or other media, ISO 1392 dry ice - acetone, Ice or water (this standard 5.2; ISO 1392. 1977, 4.5);

--- This standard simplifies the ISO 1392. specific provisions for sample drying process 1977 (ISO 1392. 1977 and 5.2.1 5.2.2.1 and 5.2.2.2; this standard 7.1);

Stop --- This standard specifies the sample was cooled with stirring, crystallization occurs when stirred; ISO 1392. 1977 stipulates that from the start of cooling the sample the proceeds stirring without allowing liquid to extreme cold, after crystallization occurs if the temperature rises more than 1 °C ~ 2 °C, should be re-measured (This standard is 7.3; ISO 1392. 1977 5.4).

This standard replaces GB/T 2385-1992 "dye intermediates determination of crystallizing point - General method." this standard compared with GB/T 2385-1992 The main changes are as follows.

--- Change the standard name is "common measurement method dye intermediate crystallization point";

--- Increased (Chapter 2 of this edition) "Normative references" chapter;

--- Increased (3rd edition chapter) "Terms and Definitions";

--- Modify the formula of full immersion thermometer measurement, increasing the formulas Bureau immersion thermometer measurement (1992 edition 7 Chapter; Chapter 8 of this edition);

--- Increase in the content of the test report (Chapter 10 of this edition).

The standard proposed by China Petroleum and Chemical Industry Association.

This standard by the National Standardization Technical Committee Dye (SAC/TC134) centralized.

This standard was drafted. Shenyang Chemical Research Institute.

1 Scope

This standard specifies the determination of crystallizing point of dye intermediates double cuff technique common methods.

This standard applies to the determination of dye intermediates crystallization point of crystallization temperature in the range of -10 °C ~ 150 °C.

This standard applies to direct measurement sample crystallization point, is also applicable to the measurement sample dried after crystallization point. Are samples need to do Dry and dry methods in product standards separately.

2 Normative references

The following documents contain provisions which, through reference in this standard and become the standard terms. For dated references, subsequent Amendments (not including errata content) or revisions do not apply to this standard, however, encourage the parties to the agreement are based on research Whether the latest versions of these documents. For undated reference documents, the latest versions apply to this standard.

GB/T 629 chemical reagent sodium hydroxide

3 Terms and Definitions

The following terms and definitions apply to this standard.

The point means a liquid crystalline material during the cooling transition from liquid to solid phase transition temperature when.

Principle 4

Liquid or melted material cooled at atmospheric pressure, when the temperature control from the liquid phase to a solid phase during the phase transition, the release of latent heat is observed the maximum temperature to maintain a certain stage of the crystallization point temperature.

5 Reagents and materials

6 Instruments and devices