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Theoretical Aspects of the Equilibrium State of Chain Crystals

  • Jens-Uwe Sommer
Part of the Lecture Notes in Physics book series (LNP, volume 714)

Abstract

The equilibrium state of polymer single crystals is considered by explicitly taking into account the amorphous fraction formed by loops and tails of the chains. Using ideal chain statistics, a general expression for the free energy excess of the amorphous part is derived. I show that tight loops and close reentries are favored under experimental conditions for under-cooling of polymer single crystals. For many chain crystals, I show that the lamellar thickness increases with the number of chains in the crystal, and that extended chain conformations are thermodynamically favored when the number of chains in the crystal is sufficiently large. The role of finite bending rigidity of chains is discussed for folded chain crystals, as well as tilt effects in extended chain crystals.

Keywords

Extended Chain Loop Length Amorphous Fraction Polymer Crystal Statistical Segment 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer 2007

Authors and Affiliations

  • Jens-Uwe Sommer
    • 1
  1. 1.Institut de Chimie des Surfaces et Interfaces (ICSI-CNRS)MulhouseFrance

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