Transport activation energy, of polymer segments

Transport Activation Energy of Polymer Segments During Isothermal Crystallization Measured by D and Polarizing Optical Microscopy... 

Mandelkern et al. (1968) have proved that the WLF formulation, which has had an outstanding success in explaining the segmental mobility and flow properties of completely amorphous polymers, is not applicable to the transport process involved in the growth of spherulites in melts of semi-crystalline polymers. Rather, a temperature-independent energy of activation, specific to a given polymer and dependent on its glass temperature, suffices to explain the experimental data now available. Mandelkern s equation reads ... 

The crystallization kinetics of heat polymers are governed by the energy barriers that must be overcome to form a critical nucleus on the crystal surface, AF, and to activate the transport of the segments across the solid-liquid interface, H. The accepted expression for the radial growth rate is... 

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