Carbon Black Dispersion Test Method

The detection method of carbon black dispersity is divided into indirect measurement method and direct measurement method.

一. Indirect measurement method: using the relationship between carbon black dispersion and other physical parameters, the dispersion of carbon black is indirectly characterized by detecting the value of physical parameters. 

The disadvantage of this method is that because these physical parameters are affected by other factors other than dispersion, it is difficult for the detection results to reflect the dispersion of carbon black directly .

二.  Direct measurement method: sample the mixed rubber directly, observe its mixing state with a certain method, and see what kind of structure it forms, the uniformity and dispersion of each component distribution. Common methods are as follows:

1. Roughness analysis method:

The surface roughness analysis method is to obtain the three-dimensional topography of the cut section of the rubber compound by means of stylus or optical interference scanning. Because carbon black will cause the cut surface to be uneven, the uneven part of the three-dimensional topography can be identified as carbon black. 

The disadvantage of this method is that there are many reasons for the uneven cutting surface of the rubber compound, such as bulge caused by bubbles and depression caused by pores, so this inspection method has a large error.

2. Surface observation method:

(1) Scanning electron microscopy: this method can detect the surface morphology, structure and composition of samples.

Advantages: high magnification, nano carbon black can be observed; 

Disadvantages: the detection conditions are harsh and need to be pumped to vacuum and cooled by liquid nitrogen. It is generally used for qualitative analysis. 

This inspection method uses a finely focused electron beam to scan the sample surface point by point. The electron beam interacts with the sample to produce various physical signals, which are received, amplified and converted into modulation signals by the detector, and finally displayed on the instrument in the form of pictures.

(2) Image microscopy: it is the most widely used carbon black dispersion detection method at present. Firstly, use the blade to cut the rubber to form a flat section, and then irradiate the light on the rubber section at an angle of 30 degrees through dark field lighting. The carbon black will show a bright color and the film is dark black. The image is transmitted to the computer through the imaging system, and the obtained image is compared with the standard image to calculate the carbon black dispersion. 

The advantages of this method are that the detection conditions are relatively simple and can realize the quantitative rating of carbon black dispersion

Our AT467 model Carbon Black Dispersion Tester is a system to determine the carbon black dispersion of polyolefin pipe, fittings and compound material. It is also suitable for pigment dispersion test. 

★ Professional image method to measure, high accuracy;

★ With standard scale ruler which provided by metrology institute to ensure the accuracy of the particle size measurement;

★ Extensive test parameters including size of carbon black pellet (equivalent diameter, area, perimeter, etc.) and shape information (roundness, rectangularity, length-width ratio, etc.);

★ Equipped with professional process program for different products to ensure reliable test result, automatically finish the process from image capture and test result output;

★ With flexible data analysis and reporting system, the test reports are saved as Excel form, convenient to save and print;

★ Can provide auto-system, improve the degree of automation

★ Can provide different capture device to connect with different computer

If you want to know more, please kindly contact us.