Ultra small angle X-ray scattering studies on density heterogeneity of linear low density polyethylene

We have investigated density heterogeneity of linear low density polyethylene (LLDPE) in the order of submicron scale with 2 dimensional ultra small angle X-ray scattering (2D USAXS). We found that power-law behaviour in small q- region of isotropic scattering patterns of LLDPE studied here, indicating that the density heterogeneity obeys mass fractal. Under stretching, isotropic 2D USAXS patterns of some LLDPE samples were transformed into butterfly patterns caused by heterogeneous deformation.