Features of Imparting Antistatic Properties to Epoxy Systems Using Carbon Nanotubes

The study investigates the development of antistatic properties in an epoxy system through the incorporation of carbon nanotubes (CNTs). The influence of CNTs of various types and manufacturers was examined. The minimum content of multi-walled and single-walled CNTs required to achieve an electrical resistivity of 106 Ω·cm was determined. A comparative analysis of multi-walled CNTs from Cabot Corporation (“Cabot” product), Graphistrength (“Arkema” product), and single-walled CNTs from CHASM Advanced Materials (Signis product, model CG300) revealed that single-walled Signis CNTs provide the required conductivity at concentrations above 0.02 wt. %, ensuring antistatic properties on the specimen surface. The effect of CNT pre-treatment technologies on the efficiency of electrical resistivity reduction in the final polymer material was analyzed. It was shown that annealing and acid treatment have only a minor effect on achieving the desired characteristics of the polymerized product. It was established that the target electrical resistivity can also be reached through mechanical deagglomeration, although ultrasonic processing remains the most effective method. Ultrasonic dispersion is feasible only at a controllably low viscosity of the system, which becomes challenging due to viscosity increase with higher CNT content, especially for single-walled nanotubes. Moreover, prolonged ultrasonic exposure imposes limitations on its practical use. Utilizing viscosity as a factor that promotes CNT deagglomeration through shear-induced mechanical mixing of the epoxy resin enables efficient and relatively rapid dispersion at a minimal content of Signis and Cabot nanotubes.