Novel nitrile-butadiene rubber composites with enhanced thermal conductivity and high dielectric constant

Nitrile-butadiene rubber (NBR) composites filled with functionalized BN platelets were successfully prepared to yield materials with high thermal conductivities and dielectric constants. To enhance the interfacial interactions between BN platelets and NBR matrix, non-covalent functionalization of poly(dopamine) (PDA) followed by covalent functionalization of gamma-(2,3-epoxypropoxy)propytrimethoxysilane (KH560) were employed for BN platelets surface modification to yield BN-PDA-KH560. This route led to good filler dispersion of BN-PDA-KH560 plateltes with decreased interfacial thermal resistances. Large thermal conductivity (0.409 W/mK) was achieved with 30 vol% BN-PDA-KH560/NBR composite. This value was 2.6 folds higher than that of pure NBR (0.157 W/ mK). The 30 vol% BN-PDA-KH560/NBR composite not only exhibited relatively high dielectric constant (9 at 100 Hz) but also remained low dielectric loss tangent (0.12 at 100 Hz). Overall, these findings provide a simple and effective route for preparing high-performance NBR composites with large thermal conductivities and dielectric constants for potential application in electronic devices.