Significantly improved dielectric and mechanical performance of Ti3C2Tx MXene/silicone rubber nanocomposites

MXenes are attracting great interest for their excellent electrical and mechanical properties. High dielectric constants have been achieved in polymer-based nanocomposites with MXenes as fillers, but these materials suffer from large dielectric losses. In this work, Ti3C2Tx MXene/silicone rubber (SR) nanocomposites were prepared because of the low dielectric loss of SR. The effects of Ti3C2Tx MXene nanosheets on the thermal stability, dielectric and mechanical performance of the nanocomposites were investigated. A dielectric constant of 6.2 accompanied by an extremely low dielectric loss of 0.001 at 103 Hz frequency was obtained in the nanocomposites when 1.2 wt% Ti3C2Tx MXene was loaded. The enhanced dielectric properties are mainly attributed to the Maxwell-Wagner-Sillars effect and the microcapacitor model. Moreover, the thermal stability of the nanocomposites can reach 450 °C. Tensile strength of 430 kPa, elongation at break of 341% and reduced elastic module of 402 kPa were also obtained in the nanocomposite with 2 wt% Ti3C2Tx MXene. This work provides a method for fabricating polymer-based nanocomposites with excellent dielectric properties under low filling content, which is crucial for modern electronic applications.