Temperature control is very important during ultrasonication. If you want to distribute CNTs more homogeneously, it may be more appropriate to use a ball milling instead of ultrasonication. You can solve the problem by using an ice bath to prevent overheating in the ultrasonication device;

With heating, the polymer in the solution may stick together and form a ball. In this context;

Dilute your polymer precursor solution with a suitable solvent (e.g. acetone).

Add CNTs to your solution (e.g. 0.1–1% by weight).

Then apply different ultrasonication times for each sample (e.g. 5 min, 15 min, 30 min, 60 min).

Mücahit Kocaman Thank you for your helpful response. I will take your suggestions into consideration. However, what I am specifically interested in is the sample preparation method for SEM imaging of the dispersion solution.

Then the solution needs to be dried beforehand. Because the liquid solution damages the system due to the vacuum operation of SEM. Therefore, the dispersion solution (CNT + polymer + solvent) is left on the glass or table. It may take 1-2 hours to dry completely. After drying, only the dry and fixed film remains. In this film, the distribution of CNTs can be determined.

Mücahit Kocaman Thank you very much.