Tailoring dielectric properties of natural rubber/millable polyurethane elastomer blends by filler embedding

The dielectric features of Natural Rubber/Millable Polyurethane elastomer (NR/MPU) blends have been effectively modulated by embedding them with nanofillers. The characteristics of the modified blends such as capacitance, dielectric permittivity, loss factor, volume resistivity, and electrical impedance have been studied, within a frequency range of 1 kHz to 10 MHz, with respect to filler loading, polymer-filler interactions, and macromolecular segmental mobility. The improvement in the dielectric properties of the systems with filler loading has been attributed to the development of micro-capacitance structures in the NR/MPU matrix which favours relaxation processes depending on the interfacial polarisation and segmental mobility.