Studies of polyethylene shish‐kebab structures

An experimental method initiated by Williamson and Busse has been extended to produce veil‐free shish kebab structures in linear polyethylene without need for severe recovery treatments. The technique involves the dilution of polymer in a concentrated solution of low molecular weight paraffin followed by a simple isothermal shear. The resulting shish kebab structures are isolated from the wax matrix and subjected to electron microscopical and electron diffraction study. From the diffraction patterns, it is shown that the shish‐rich ordered structure is similar to the orthorhombic structure of crystalline linear polyethylene, but with certain significant deviations. The resolvable morphology of the shish appears to be characterized by a length‐to‐diameter ratio which is consistent with a prediction based upon Wulff's theorem utilizing certain relevant surface energy values which have been obtained by others for polymeric crystals.