Improvement of the properties of ground tire rubber (GTR)‐filled nitrile rubber vulcanizates through plasma surface modification of GTR powder

The surface modification of ground tire rubber (GTR) powder to enhance its adhesion to nitrile rubber (NBR) vulcanizates was investigated. The hydrophobic surface of GTR powder has been transformed to a hydrophilic one through atmospheric pressure dielectric barrier discharge (DBD). The water contact angle dropped markedly from 116 to 0° after being treated for more than 10 s. Attenuated total reflectance Fourier transform infrared spectral (ATR‐FTIR) studies revealed the increase in peak intensity at 3298 and 1640 cm^?1 that correspond to O? H and C?C, respectively, on the surface of the GTR powder. The X‐ray photoelectron spectroscopic (XPS) analysis further confirmed the presence of oxygen containing polar functional groups on the surface of the GTR powder after atmospheric plasma treatment. The improvement in tensile strength and tear strength was observed for the modified GTR‐filled NBR vulcanizates, which is attributed to the enhanced interfacial interaction between modified GTR and NBR matrix. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009