A quantitative electron-microscopic study of a linear polyethylene fraction crystallized at different temperatures

Replica and thin-section electron microscopy was performed on a linear polyethylene fraction (M_w = 1.89 × 10⁵, M_n = 1.79 × 10 ⁵) which was either isothermally crystallized or quenched at difference temperatures. The results are numerically analyzed in such a manner so as to give the distribution of the total long spacing and of the crystallite and amorphous thicknesses. The quantitative information about the maximum and minimum values for these parameters at each crystallization temperature yields important clues as to possible molecular processes involved. Qualitative information regarding general morphology, molecular tilt with respect to the lamellar surface, and possible crystallographic faults are also discussed.