Morphology of CaCO3‐filled polyethylenes

The morphology of one novel “homogeneous composite” and some conventional CaCO3‐particulate‐filled polyethylenes (PEs) has been investigated by transmission and scanning electron microscopy. It is found that for three different linear polyethylenes (Mw = 37,000, 200,000, and 1.5 × 106) studied, ordering on the scale of spherulites was absent in the CaCO3‐filled polymer. However, PE lamallae were observed growing normal to the filler interface. Changes in molecular weight of the polyethylene result in easily observed differences in morphology, while DSC studies indicate that crystallinity decreases in the presence of filler for the two lower‐molecular‐weight polyethylenes.