Discrete Reflections from Lamellar Structures

Polymer chains in semicrystalline polymers such as polyolefines, aliphatic polyamides (nylons), and aliphatic polyesters crystallize in the form of lamellae of folded chains that are organized to form lamellar stacks (Fig. 2.14a). The spaces between the lamellae and between the stacks are occupied by 

A plot of Z2 versus is a straight line with slope of (-b la ) and an intercept of b as given by the relation 

The elliptical trace corresponds to the deformation of the lamellar lattice, and the disposition of the reflections along this trace reflects the orientation of the lamellae in this lattice [103]. One possibility is that as the lamellar spacing increases, the lateral distance between the adjacent lamellar columns decreases. Absence of any correlation between adjacent lamellar columns results in an eyebrow pattern (Fig. 2.16b). However, if the tilt 

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