A model for the crystallization kinetics of polymers is outlined and is used to interpret observations of the crystallization of PE at high pressures. This model introduces a distinction between sigma //e the lamellar surface energy which controls the lamellar thickness, and sigma //e', the surface nucleus surface energy which controls the growth rate. Differential scanning calorimetry and electron microscopy data for several polyethylenes crystallized at pressures of up to 8 kb are preseinted. It is found that sigma //e increases markedly with pressure leading to the formation of very thick crystals at high pressures. Fractionation effects and the differences in behavior between different polyethylenes are also discussed.
|Original language||English (US)|
|Number of pages||26|
|Journal||J Polym Sci Part A-2 Polym Phys|
|State||Published - Sep 1972|
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