Nano‐BN/Nano‐TiO 2 and micro Mg(OH) 2 loaded hybrid ethylene propylene diene monomer elastomer composites for outdoor high‐voltage insulation application

This work deals with the synthesis, characterization of hybrid ethylene propylene diene monomer (EPDM) composites loaded with nano‐boron nitride (nano‐BN)/nano‐titanium dioxide (nano‐TiO 2 ) and micro Mg(OH) 2 particles for its suitability towards high‐voltage insulation application. The elastomer samples were prepared by carefully dispersing the micro and nano fillers during the mastication process of EPDM polymer using a two roll mill, followed by vulcanization. The samples were characterized for mechanical, morphological, thermal, and electrical insulation properties. The highest tensile strength among the composite samples was noted for 1 phr nanoparticles loaded samples. Fourier Transform Infrared (FTIR) results show no change in the chemical moiety upon addition of nano‐BN/nano‐TiO 2 in EPDM composites. Enhancement in hydrophobicity is observed for 3 phr nano‐TiO 2 loaded composites, which shows a maximum static contact angle of 110°. Meanwhile remarkable enhancement in the thermal conductivity and volume resistance of the composites are contributed to the addition of nano‐BN, thereby achieving maximum dielectric breakdown voltage (i.e., ~21 kV/mm for EMB3). Scanning electron microscope images and atomic force microscopy (AFM) topography highlight that low concentration (i.e., 1 phr) based composites have homogeneous dispersion in matrix and excessive nano filler addition deteriorates properties by forming filler aggregates and increasing surface roughness.