Quantitative Analysis Of Metal Fiber In Radiation Protection Maternity Dress

In recent years,

2 experiment

2.1 test sample: polyester cotton and all cotton metal wire fabric (metal wire can be split from fabric).

2.2 main reagents: concentrated sulfuric acid, sulfuric acid (mass fraction of 75%), sulfuric acid (mass fraction 50%), dilute ammonia solution (80mL concentrated ammonia water diluted with water to 1L), distilled water.

2.3 main equipment and instruments: with plug triangle flask, glass rod, constant temperature oscillating water tank, analytical balance (accuracy 0.0001g), constant temperature blast oven, and filter device.

2.4 test methods and procedures

1) weight method: manually separate metal fibers from fibers, handle them, weigh them and calculate them.

2) sulfuric acid method

(1) the weight of the metal fiber is calculated by using the sulphuric acid (mass fraction 75%) dissolved cotton method.

According to the general procedure stipulated by GB/T2910.1.

Then put the prepared sample into the triangular flask, add 200mL sulphuric acid (mass fraction 75%) into the flask and plug the glass stopper on each gram sample. Shake the flask and moisten the sample thoroughly. Keep the flask at (50 + 5) C at 1H and shake it every 10min.

A glass core with a known drying quality is used to filter the solution.

The residue is filtered into the crucible of the glass core, vacuum suction and drainage, and a small amount of sulfuric acid is used to clean the flask. Vacuum suction is used to drain the liquid. The new sulfuric acid solution is added to the crucible and the residue is clear. The gravity drainage is at least 1min after vacuum pumping, and the water is washed continuously for several times. Dilute ammonia water and two times are washed with cold water.

After each washing, gravity drainage and suction drainage are performed.

Finally, the crucible and residue were dried, cooled, weighed and calculated.

(2) for polyester fiber metal fabrics, we use heavy sulfuric acid to dissolve polyester fibers to calculate the weight of metal fibers.

According to the general procedure stipulated by GB/T2910.1.

Put the sample into a triangular bottle, add 100mL concentrated sulfuric acid to each gram of sample, and stir the sample with glass rod continuously when 10min is placed at room temperature.

A glass core with a known drying quality is used to filter the solution.

Add 100mL concentrated sulfuric acid into the triangular bottle, repeat the above operation.

The contents of the bottle were poured into the crucible of the glass sand core. After vacuum pumping, filtration, emptying or replacing the filter bottle, 50mL sulfuric acid solution, distilled water and dilute ammonia solution were used successively. Finally, the residue in the crucible was washed with distilled water.

Finally, the residue and crucible were dried, cooled, weighed and calculated.

1) from the above test data, we can see that there is no significant difference between the metal fiber content measured by gravimetric method and the metal fiber content measured by sulfuric acid method, and the error is within the confidence range. Therefore, for the non detachable fabric, the method of measuring the content of metal fiber by sulfuric acid method is also feasible, and the measured data are reliable.

2) the data measured by the sulfuric acid method are too large because the metal fiber and sulfuric acid may produce a little sulphate on the surface of the metal fiber, but the error caused by this method is within the confidence range.