Crystal lamella sectorization, polyethylene

Early experiments on solution-grown lamellae revealed not only the earlier melting of the 100 sectors in polyethylene lamellae (25) [which Atomic Force Microscopy (AFM) has confirmed (33) to be thinner than 110 sectors in collapsed, and presumably as-grown, crystals] but also the presence of holes (43) in lamellae that had been heated in contact with a carbon film (Fig. 2). While providing clear evidence of lamellar thickening, the presence of holes is a response to the carbon film, which restrains lateral contraction holes do not appear on thickened upper layers of the same sample that are not so restrained. 

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