In-situ modification of nanodiamonds by mercapto-terminated silane agent for enhancing the mechanical interfacial properties of nitrile butadiene rubber nanocomposites

(3-Mercaptopropyl)trimethoxysilane (MPTMS)-ethanol-solution-treated nitrile butadiene rubber/nanodiamond (NBR/ND) polymer-matrix nanocomposites were prefabricated in situ using a facile environmentally friendly one-pot design. The MPTMS-modified ND (MND) and pristine ND were characterized using wide-angle X-ray diffraction, Fourier-transform infrared spectroscopy, transmission electron microscopy, N₂ adsorption analysis, thermal gravimetric analysis, and X-ray photoelectron spectroscopy. The pristine ND exhibited a high specific surface area and abundant active organic groups, especially hydroxyl and carboxyl groups, thus confirming its hydrophilic properties. The successful fabrication of surface-modified MND was also verified. The fracture surface morphologies of the NBR/MND nanocomposites were analyzed using high-resolution scanning electron microscopy and field-emission transmission electron microscopy, and the dynamic rheological properties of the NBR/MND nanocomposites were characterized using a rubber processing analyzer. The NBR/MND composites exhibited superior mechanical properties, which were attributed to the strong interfacial interaction of the MND particles with the NBR matrix via MPTMS linking. POLYM. COMPOS., 39:3472–3481, 2018.