DEPENDENCE OF ELECTRICAL RESISTANCE ON PARAMETERS OF THE CRYSTAL STRUCTURE AND PHYSICO-CHEMICAL CHARACTERISTICS OF CARBON BLACK

CZOHYD

Abstract

Electrically conductive polymer composite materials (PCM) with carbon fillers have become widely used as materials for electrical and radio engineering purposes. The most important target characteristic of such materials is their electrical conductivity, which depends on the complex of factors. The most significant factor determining the electrical conductivity of a polymer composite material is the electrical conductivity of the filler, which largely depends on its structure. One of the most common fillers used in the creation of electrically conductive PCMs is carbon black. The paper presents a comparative analysis of the electrical resistivity and parameters characterizing the structure for various grades of conductive carbon black produced by Omsk Carbon Group. A comprehensive study of carbon black was carried out: X-ray diffraction analysis and electron microscopy were carried out, electrical resistivity, oil absorption index, surface area for multipoint nitrogen adsorption, external surface area for nitrogen were measured. The following structural parameters were calculated: the fraction of the surface area of CB pores with a diameter of less than 2 nm, the coefficient of surface roughness of CB, the fraction of the marginal carbon atoms of CB graphene layers. A correlation has been established between changes in the electrical resistivity of CB and its physico-chemical characteristics: the oil absorption index (DBP), the surface area for multipoint nitrogen adsorption (NSA), the external surface area for nitrogen (STSA), the average size of crystallites along graphene layers. It is shown that the dependence of the electrical resistivity on the structural parameters is satisfactorily described by linear regression equations. The obtained results can be used to select electrically conductive carbon black when creating composite materials for electrical and radio engineering purposes.