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Self-healing materials are an essential emerging class of smart materials, capable of repairing their damage after external stimuli, especially mechanical damages. However, the lack of studies on self-healing polymers after electrical breakdown is highly important for electrical engineering and electronics. We propose to use a nickel­(II)-2,6-pyridinedicarboxamide-co-polydimethylsiloxane complex (NiPyPDMS) as an electrical breakdown protective material. To provide the absence of dust deposition from ambient air and to increase durability, we fabricated multilayered polymer “sandwiches” consisting of a NiPyPDMS layer covered with two films (polypropylene (PP) or polydimethylsiloxane (PDMS)) on both sides. Multilayered PP-NiPyPDMS-PP and PDMS-NiPyPDMS-PDMS films exhibit autonomous self-healing properties (up to 75%) after electrical breakdown at room temperature. NiPyPDMS demonstrates 3.7 times higher adhesion to copper, from which power lines are made, compared to PDMS. NiPyPDMS also exhibits antistatic and redox properties (NiII/NiIII transformations when electricity is applied). All characteristics mentioned above lead to reduce the probability of electrical breakdown via electrical charge dissipation in self-healing coating on possible power lines.

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Solid state sintered pellets of barium hexaferrite were performed. The Curie temperature of BaFe12O19 pellets were measured with differential scanning colorimetry (DSC). The coefficient of thermal expansion (CTE) of pellets was defined above and below the Curie temperature. The Curie temperature calculated basedon the dilatometry is are in good agreement with the DSC measurements.