First, the definition of carbon black dispersion

Carbon black is a commonly used filler, widely used in rubber, plastic, paint, ink, printing and other industrial fields. The performance of carbon black directly affects the quality and service life of the product, and the dispersion of carbon black is one of the important factors affecting the performance of carbon black. Carbon black dispersion refers to the uniform distribution of carbon black in the substrate, that is, the comprehensive performance of factors such as the size, shape, quantity and dispersion state of carbon black particles. The dispersion of carbon black is good, so that the filler can give full play to its strengthening, hardening, blackening, toughening and other functions.

Second, the test method of carbon black dispersion

Image microscopy (DZ3600) : cut the flat thin section of the pipe surface with a blade, soften the section with a thermostat, and then collect pictures through a microscope. Compare the standard pictures to grade the carbon black dispersion of the pipe.

Determination of dispersion of carbon black for pipes

3. Operation steps of image microscopy (DZ3600)

1. The smooth section of the pipe surface was cut with the surgical blade and placed on the slide. A total of 5 samples were cut at different positions. Put it in the incubator at 200℃ for 10-20min;

2. Set the calibration file: a takes a clear picture of the scale with a 10X microscope, b opens the scale picture on the carbon black dispersion analysis software and selects a distance to calculate the scale factor, which is the calibration file for judgment;

3, the sample of 200℃ constant temperature with 100X microscope to take clear pictures and name and save;

4. Use the carbon black dispersion software to open the picture and move the field of view to the position where there are many carbon black particles, then analyze the gray distribution and threshold of the picture (select the starting point of gray scale rise), fill in the threshold, and click the grade judgment;

Determination of dispersion of carbon black for pipes

5. Repeat the test to analyze and judge other samples and then take the average value.

Iv. Analysis of experimental results

Carbon black content (quality) and carbon black dispersion play a crucial role in the weather resistance of the pipe. At present, all ISO, EN and national standards stipulate that the production of PE100 gas pipelines and water supply pipelines must use black mixture. The carbon black content of mixed ingredients should be carbon black with particle size less than 25 nm, carbon black content not less than 2.0%, and carbon black dispersion ≤3.