Thermal and fluctuation-induced deformations of chemical bonds in surface and boundary layers of polymers

The deformation of chemical bonds in polymer molecules of surface layers of samples, boundary layers between supramolecular aggregates, and boundary layers between polymers and solids in polymer composites is investigated using IR and Raman spectroscopy. It is found that the chemical bonds are elongated on a free surface and in boundary layers between supramolecular aggregates. By contrast, the chemical bonds are contracted in boundary layers between polymers and solids. The concentration and the strain of excited chemical bonds (strained to approximately a theoretical ultimate elongation) are increased on the free surface and in the boundary layers between supramolecular aggregates, whereas the concentration and the strain of excited chemical bonds in the boundary layers between polymers and solids are decreased. These effects are explained by the changes in the atomic vibrations in the surface and boundary layers.