Structural Ordering in Nanotube Polymer Composites

The structural properties of carbon nanotube (CNT) polymer composite interfaces have been studied through molecular dynamics simulations. Polymer (polyethylene) molecules are found to form discrete adsorption layers as a function of radial distance from the axis of the nanotube. The molecules within the adsorption layers prefer to align parallel to the tube axis. A structural order parameter of orientation, S Z, has been investigated in detail and shows a discrete peaking behavior that is in correlation with the peaks in the density distribution function. An increase in the structural order parameter has been shown to contribute to the mechanical modulus of the composite, and the orientation-related changes have been found to be inelastic in nature.