(165s) Structure and Wear Rate of Epoxy Clay Nanocomposites

Epoxy clay nanocomposites are viscoelastic with dependence on inter-particle interactions reflected in increase in elasticity with nanofiller concentration. The wear volume and specific wear rate as a function of sliding distance for pure Epoxy and organically modified clay nanocomposites are found that the wear volume loss increases with increase in sliding distance for all the nanocomposites. Wear volume loss showed an upward trend in the gradient, as the sliding distances were increased in case of pure Epoxy. Separation of matrix in the composite is very much limited with the content of organically modified montmorillonite nanoclay particles found in the shape and size of the wear debris for organically modified nanoclay composite.

Nano clays of montmorillonite organically functionalized were mixed with Epoxy in a high shear mixer. Effect of epoxy resin cross-linking degree on interface thickness was characterized for viscoelastic modulus and tan delta. . Storage modulus (E′), loss modulus (E″), cross-link density and glass transition temperature (T_g) of the nanocomposites were improved with organoclay loading up to a threshold in concentration. Beyond the loading limit, the deterioration of properties was observed. Compared with viscous modulus, elastic modulus at different crosslinking level in the nanocomposite showed significantly larger differences from nanocomposite with uncrosslinked epoxy. Tan delta, ratio of viscous to elastic modulus, internal friction decreases with increased crosslinking and addition of nanofiller. Nanoclay organically modified epoxy showed structures by X-ray diffraction and TEM with significant exfoliation. Viscoelastic modulus was used to identify exfoliation in nanocomposites using internal friction by dynamic viscoelasticity. Improvement in the tribological behavior (wear rate) of Epoxy-organically modified clay MMT as a result of increase in elastic modulus and lower internal friction nanocomposite is predicted by the model.