Diazonium Modification of Inorganic and Organic Fillers for the Design of Robust Composites: A Review

This review focuses on fillers modified with diazonium salts and their use in composites. We reviewed scientific publications and presented information about such diazonium-modified fillers as boron nitride, carbon fillers, cellulose, clay, silica, titanium dioxide, and zeolite. The fillers were divided into two groups. The first group includes those that form covalent bonds with the polymer, while the second includes those that do not form them. This review indicates a tremendous impact of filler modification using diazonium salts on the properties of composites. The review presents examples of the impact of filler on such properties as thermal conductivity, thermal stability, and mechanical properties (e.g., interfacial shear strength, compressive strength, flexural strength). The presented review indicates the enormous potential of composites with diazonium-modified fillers in control drug release, antistatic coatings, electrode materials, photocatalysts, bone tissue engineering scaffolds, fuel cell applications, abrasive tools, and electromechanical strain sensor. We hope that this review will help both research groups and industry in choosing fillers for given types of polymers and obtaining composites with even better properties.