Growth slice formation

Early work by Hartman and Perdok described crystal growth in terms of the formation of strong bonds between neighboring crystallizing units. Uninterrupted straight chains of these bonds were classified as Periodic Bond Chains (PBC). This theory led to the classification of three types of crystal faces F-faces (flat), S-faces (stepped), and K-faces (kinked) based on the number of PBCs in a slice thickness, dhki- K-faces, which had no PBCs present in a slice, were shown to be... 

Heat transfer considerations had not yet been applied. It was tacitly assumed that the investigated slice of polymer was so thin that a quench to a certain level of supercooling could be carried out in such a short time that virtually no nucleation and crystal growth would occur within this time span. So everything which contributed to the formation of the crystalline texture was thought to occur under "isothermal conditions" at the chosen level of supercooling. As is well-known, with dispersed primary nucleation one obtains a spherulithic structure in polymers. 

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