Oxygen, solid orientational dependence

The effect of orientation on the oxygen permeability is dependent upon the morphological nature of the barrier resin prior to orientation. For the semicrystalline polymers, VDC copolymer, and aromatic nylon MXD-6, little change was observed in the permeability with orientation from the solid-state. However, solid-state orientation of the amorphous polymers SELAR PA 3426 and XHTA-50A was shown to decrease permeability by 5-30% in both resins, depending upon the level of orientation. 

In summary, through the use of a simple type of XPS(0), the molecular orientation at the surface of sulfonated PS films has been determined. In the more sulfonated films the sulfur and oxygen atoms reside preferentially below the surface, as their respective XPS(6) core-level signals decrease with increasing 0 faster than the matrix C(l ) signal. These results are corroborated by surface energy measurements that also indicate that the accessibility of the sulfonate groups depends on associative interactions in the solid. In particular, it appears that a preferential... 

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