GB/T 7571-2008Wool -- Determination of solubility in alkali (English PDF)

Foreword

This revised standard adopts ISO 3072. 1975 "wool in alkali solubility determination." this standard and ISO 3072. 1975 as compared to the main differences are as follows.

--- Normative references in the ISO standard to replace the corresponding national standards;

--- Increased test requirements with distilled water;

--- Increasing the calculation result decimal point digits requirements;

--- Modify the solubility of the base formula of representation.

This standard replaces GB/T 7571-1987 "wool in alkali solubility determination." this standard compared with GB/T 7571-1987, the main changes are as follows.

--- Increased test requirements with distilled water;

--- Increasing the calculation result decimal point digits requirements.

The standard proposed by China Textile Industry Association.

This standard by the National Standardization Technical Committee Textile basic standards Sub-Committee (SAC/TC209/SC1) centralized.

This standard wool and linen by the Shanghai Textile Research Institute of Science and Technology is responsible for drafting.

1 Scope

This standard specifies the method for determination of wool in alkali solubility.

This standard applies to wool and its products. This test should be used as untreated as control tests, such as two kinds of samples after each other this has the opposite effect on the solubility of the role, the test results are not necessarily able to explain the problem, should complement other tests.

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.

Preparation of GB/T 601 chemical reagent standard titration solution GB/T 6682 analytical laboratory use specifications and test methods (neqGB/T 6682-1992, ISO 3696. 1987) GB/T 7570 Determination of the amount of acid wool (GB/T 7570-2008, ISO 3073. 1975, MOD) GB/T 8170 numerical rounding rules Principle 3 at a specific temperature and time conditions, the wool sample in sodium hydroxide solution percentage mass loss account before drying process quality sample Rate, is wool alkali solubility.

4 Reagents

In the analysis reagents used were of analytical grade and distilled water for the three water GB/T 6682 regulations.

4.1 0.1mol/L sodium hydroxide (NaOH) solution.

According to GB/T 601 formulation.

4.2 1% (volume fraction) acetic acid (CH3COOH in) solution.

4.3 dichloromethane (CH2Cl2).

5 Instruments

5.1 Soxhlet extractor. capacity of not less than 150mL, flask capacity of not less than 250mL.

5.2 temperature water bath. temperature control (65 ± 0.5) °C (temperature controller available, water should be agitated to ensure uniform temperature).

5.3 plug Erlenmeyer flask. capacity of 250mL (same bottle wall thickness).

5.4 weighing bottle, dryer.

5.5 suction bottles.

5.6 Analytical balance. accuracy 0.0002g.

5.7 thermostatic oven. to maintain the drying temperature (105 ± 3) °C.

5.8 crucible. Capacity 30mL ~ 50mL, pore diameter is 40µm ~ 80µm.

6 Sample preparation