0000000001036760
AUTHOR
W. M. Ewers
Influence of surface morphology on melting of polymer crystals II. Loops of random length and partially random reentry
Abstract The melting behavior of single crystals with loops of random length and partially random reentry has been calculated under two different assumptions: (1) at each temperature the loops have an equilibrium end-to-end distance distribution and (2) a certain end-to-end distance distribution of the loops, ω(h), determined by the kinetics of the crystallization is frozen in and maintained during the whole heating process. The ω(h) is calculated by considering the loop formation process during crystallization and by introducing a parameter λ which expresses the tendency of the chains for adjacent reentry. In both cases a melting range is obtained. In case 2, the melting range depends stro…
Berechnung der Schlaufenendenabstandsverteilung bei der Bildung von Kristallen aus Kettenmolekülen
In verschiedenen kristallisationskinetischen Theorien (1–5) wird davon ausgegangen, das sich Kristalle mit regelmasigen Kettenfalten an den Grund- und Deckflachen ausbilden, wie in Abb. 1a angedeutet. Das Entstehen von derartigen Kettenfalten wird damit begrundet, das der herausragende Teil eines soeben in den Kristall eingebauten Molekuls den kleinsten Weg bis zur Kristallisationsfront hat.