A novel rubber filler, black liquor–montmorillonite complex (BL–MMT) was prepared by dehydration of a mixture of MMT and BL and used in the preparation of acrylonitrile butadiene rubber (NBR) composites by mechanical mixing method. The BL–MMT/rubber composites were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and differential scanning calorimeter (DSC). Experimental results of XRD and TEM indicated that MMT was well-dispersed in the rubber because of the presence of lignin. DSC, thermo-oxidative aging measurements and TGA results demonstrated that the thermal properties of NBR were improved due to the addition of BL–MMT. The tensile properties including tensile strength, elongation at break, and modulus were also tested. All experimental results indicated that this BL–MMT complex could be an effective reinforcing agent in rubber for cost-saving and environment benefits
