In accordance with the present teachings, there are composite materials, fuser members comprising the composite materials, and methods of making the composite materials. In various embodiments, the composite material can include a polyimide resin having a thermal conductivity and a plurality of passivated aluminum nitride particles substantially uniformly dispersed in the polyimide resin to provide the composite material with a thermal conductivity of about 0.4 W/mK to about 2.5 W/mK, and wherein each of the plurality of passivated aluminum nitride particles can include a passivation layer disposed over an aluminum nitride particle core to inhibit oxidation and thermal degradation of a surface of the aluminum nitride particle core.