Thermal, mechanical and morphological properties of surface-modified montmorillonite-reinforced Viton rubber nanocomposites

摘要

Thermal, mechanical and morphological properties of surface-modified montmorillonite (OMMT)-reinforced Viton rubber nanocomposites were studied. The surface of montmorillonite was modified with a column chromatography technique using quaternary long-chain ammonium salt as an intercalant, which resulted in uniform exchange of ions between montmorillonite and the ion-exchange resin, and increased the d-spacing to 31.5 A. This improved d-spacing was due to the use of an ion-exchange column of sufficient length (35 cm) and diameter (5 cm) with maximum retention time for exchange of ions. The Viton nanocomposites reinforced with OMMT (3-12 wt%) were prepared using a two-roll mill and moulded in a compression moulding machine. Tensile strength increased 3.17 times and elongation at breakfrom 500 to 600% for 9 wt% loading of OMMT in comparison to pristine Viton rubber. Thermogravimetric analysis revealed that the presence of OMMT greatly improved the thermal stability. This improvement in properties with increasing OMMT loading was due to insertion of rubber chains between the OMMT plates with good wetting ability. Overall, at an optimum OMMT loading of 9 wt%, the properties of the Viton rubber nanocomposites improved, and subsequently worsened at 12 wt% due to agglomeration of OMMT as revealed by scanning electron microscopy and atomic force microscopy images.