โ Scribed by V.I. Vettegren; A.E. Tshmei
No coin nor oath required. For personal study only.
Highly oriented polymer films were stretched along the axis of orientation. Using i.r. transmission and reflection spectroscopy, the scission of polymer molecules under stress in the volume and in the surface layer ~ 1/~m thick was studied. The accumulation of scissions of chemical bonds in the surface layer was found to be at least an order more intense than that in the volume. It is shown that this phenomenon is due to considerable heterogeneity of external load distribution over chemical bonds near the surface. It is inferred that the surface plays a leading role in the fracture mechanism of polymers.
The intensity of the intermolecular interactions in the volume and on the surface of polymers was studied and was found to be lower in the surface layer. It is proposed that the role of surface in the fracture process results from weakening of the intermolecular interactions.
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