Determination of dispersion of carbon black in pipe materials

　　1、 Definition of Carbon Black Dispersion

Carbon black is a commonly used filler, widely used in industrial fields such as rubber, plastics, coatings, inks, and printing. The performance of carbon black directly affects the quality and service life of products, and the dispersion of carbon black is one of the important factors affecting its performance.Dispersion of carbon blackIt refers to the degree of uniform distribution of carbon black in the substrate, which is the comprehensive manifestation of factors such as the size, shape, quantity, and dispersion state of carbon black particles. Good dispersion of carbon black allows the filler to fully exert its reinforcing, hardening, blackening, toughening and other effects.

　　2、 Test method for dispersion of carbon black

Image microscopy method (DZ3600): Cut a flat thin section of the pipe surface with a blade, soften the section with a constant temperature chamber, and collect images through a microscope. Compare the standard images to evaluate the dispersion of carbon black in the pipe.

　3、 Operation steps of image microscopy method (DZ3600)

1. Cut the flat surface of the tube with a surgical blade and place it on a glass slide, cutting a total of 5 samples at different positions. Place it in a constant temperature box and set it at 200 ℃ for 10-20 minutes;

2. Set calibration file: a. Take a clear ruler image with a 10X microscope, b. Open the ruler image on the carbon black dispersion analysis software and select a distance to calculate the scaling factor, which is the calibration file for judgment;

3. Take clear pictures of the sample that has been kept at a constant temperature of 200 ℃ using a 100X microscope and name and store them separately;

4. Open the image using the carbon black dispersion software and move the field of view to a location with more carbon black particles. Then analyze the grayscale distribution and threshold (select the starting point of grayscale rise) of the image, fill in the threshold, and click on the level judgment;

5. Repeat the test and analyze other samples to determine the average value.

4. Analysis of experimental results

The carbon black content (quality) and carbon black dispersibility play a crucial role in the weather resistance of pipe materials. Currently, all ISO, EN, and standards require the use of black blending material for the production of PE100 grade gas and water pipelines. The carbon black content of the mixed ingredients should be carbon black with a particle size of less than 25 nm, a carbon black content of not less than 2.0%, and a carbon black dispersibility of ≤ level 3. For more information about carbon black content dispersion instruments, please consult:.