Structural, electrical, and physical–mechanical properties of composites obtained based on filled polyolefins and thermoplastic elastomers

Abstract

The paper presents the results of a study of the influence of various mineral and metal fillers, as well as carbon black and graphite on the structural features and quality of composite and nanocomposite materials based on polyolefins and their modifications. High density polyethylene (HDPE), low density polyethylene (LDPE), various copolymers of ethylene with α-olefins, polypropylene (PP), polypropylene random copolymer, block copolymer of ethylene with propylene, etc. were used as polyolefins. The filler used was mainly carbon black (CB) and graphite, as well as various natural minerals. The objective of the review material under consideration was to demonstrate promising possibilities for obtaining electrically conductive composite and nanocomposite materials based on dielectric polymers, which are included in the polyolefins. The introduction section examines the state of the problem of development and research of electrically conductive nanocomposites, as well as the goals and objectives of the research. The theoretical aspects of obtaining and studying composite materials based on polyolefins are considered, where the main attention is paid to studying the influence of filler content on the structural features and properties of polymer composites. Particular attention is paid to the compatibility of the mixture components and the establishment of the relationship between the filler particles and the macrochains of the polymer matrix. The significant role of compatibilizers in improving the compatibility of mixture components is shown. The article presents scientific provisions and theoretical background that explain the mechanism of the compatibilization process and its influence on the pattern of changes in electrical conductivity, physical, mechanical, thermophysical and thermal deformation properties of nanocomposites. Much attention is paid to the development of thermoplastic elastomers, taking into account the specifics of the interaction of thermoplastic (polyolefin) macrochains with various synthetic elastomers based on natural, butadiene-nitrile, butadiene–styrene and ethylene–propylene–diene rubbers. The influence of the thermoplastic-elastomer ratio, carbon black and graphite, and their modifications on the structure and properties of nanocomposites based on thermoplastic elastomers is considered. Significant attention is paid to the study of electrical conductivity of nanocomposites based on thermoplastic elastomers. It has been established that the degree of crystallinity of polyolefins and thermoplastic elastomers has a significant effect on the formation of the interspherulitic amorphous region in filled composites, which, in turn, has a primary effect on the mechanism of formation of tunnel and electron conductivity.