Reinforcing effect of organoclay in nitrile rubber - Effect of mill mixing and latex stage mixing

Abstract The urge for materials with diverse applications has paved the way to fabricate composites based on, one-dimensional filler like nanoclays. The main aim of the work was to study the effect of mill mixing and latex stage mixing on the reinforcing effect of organoclay in Nitrile Rubber. The non-ionic surfactant assisted latex stage mixing route proved to be more efficient and feasible when compared to mill mixing. Mechanical properties were measured and, about 150% increase in tensile strength and 79% increase in tensile modulus were obtained for the latex based composites at 3 phr clay loading when compared to neat rubber composites. Dynamic strain sweep tests revealed that, the low strain modulus for latex mixed composites was higher. Thermogravimetric analysis (TGA) and Differential Scanning Calorimetry (DSC) results indicated that the addition of organoclay hardly affected the thermal properties of the rubber matrix. Transmission Electron Micrographs revealed homogeneous dispersion of partially exfoliated and intercalated nanoclay platelets in the latex state substantiating the viability of latex mixing over mill mixing. The extent of reinforcement in the nanocomposites was also analyzed with the help of different micromechanical models.