Role of polymer‐filler interaction on Mg(OH)2 and alumina trihydrate‐loaded ethylene propylene diene monomer based polymer composite for high voltage insulation application

Abstract Use of polymer composite as a high voltage insulator material is currently under investigation for its commercial application, longer durability, and cost effectiveness. This work probes the effect of polymer‐filler interaction on mechanical, morphological, thermal and dielectric properties of ethylene propylene diene monomer (EPDM) based polymer composite. EPDM composites were successfully prepared using two roll‐mill and vulcanized in a hot press compression mold. Surface morphology indicates uniform dispersion of filler at lower filler loading, whereas at higher loading cluster/agglomeration was observed. 30 phr magnesium hydroxide (Mg(OH) 2 ) loaded sample showed the highest static contact angle of 102.3°. Mg(OH) 2 based samples show higher tensile strength because of strong interfacial interaction between filler and polymer. In addition, alumina trihydrate (ATH) and Mg(OH) 2 based composite exhibit high thermal stability with initial thermal degradation temperature of ~200 and ~320°C, respectively. FTIR spectrum reveals the formation of strong –OH bonds between Mg(OH) 2 and polymer molecules. A maximum enhancement in dielectric breakdown strength of ~50% and ~30% were recorded for 60 phr ATH and 30 phr Mg(OH) 2 loaded EPDM composites respectively. Finally, the results indicate a strong possibility of developing EPDM based polymer composites as an efficient high voltage insulator.