Influence of ionic liquid on the polymer–filler coupling and mechanical properties of nano-silica filled elastomer

The natural rubber (NR) nanocomposites were fabricated by filling ionic liquid (1-allyl-3-methyl-imidazolium chloride, AMI) modified nano-silica (nSiO2) in NR matrix through mechanical mixing and followed by a cure process. Based on the measurements of differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), solid state nuclear magnetic resonance spectroscopy, and Raman spectroscopy, it was proved that AMI could interact with nSiO2 through hydrogen bonds. With the increase of AMI content, the curing rate of nSiO2/NR increased. The results of bound rubber and dynamic mechanical properties showed that polymer–filler interaction increased with the modification of nSiO2. Morphology studies revealed that modification of nSiO2 resulted in a homogenous dispersion of nSiO2 in NR matrix. AMI modified nSiO2 could greatly enhance the tensile strength and tear strength of nSiO2/NR nanocomposites. Compared to unmodified nSiO2/NR nanocomposite, the tensile strength of AMI modified nSiO2/NR nanocomposite increased by 102%. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 134, 44478.