Dielectric and pyroelectric properties of nylon 5,7 as a function of molecular orientation

Abstract

Abstract Nylon 5,7 has been made in film form with two different molecular orientations. X-ray studies show that the H-bonds in rolled and annealed Nylon 5,7 are oriented approximately perpendicular to the film surface. Because of this, the film has a low dielectric response and reasonably high pyroelectric response. In gold nucleated, directionally crystallized Nylon 5,7 the H-bonds are oriented parallel to the film surface. Such films have a high dielectric response and low pyroelectric response. This can be understood in the light of the proposed model of H-bond twinning. The disappearance of the alpha relaxation in film A was ascribed to pinning of the amorphous phase since the oriented film was annealed under tension. High temperature dielectric loss of film A follows Jonscher's power law with n close to 1 showing that it is probably due to ionic conduction. Dielectric loss in film B gives an n value of 0.30 in the temperature range of 130–160°C, indicating that much of the loss is not due to ionic c...