Study of Anisotropy of Acoustic Wave Propagation in Stretched Poly(vinylidene difluoride) Film Using the Picosecond Transient Grating Technique.

摘要

The picosecond transient grating technique has been used to obtain acoustic speed as a function of film orientation in a uniaxially stretch-oriented film of poly (vinylidene difluoride) at liquid nitrogen temperature. By the analyses of acoustic speed anisotropy using the general Christoffel equation, we have obtained both the longitudinal and shear components of the elastic moduli of the film. Our results are in a qualitative agreement with those of a published Brillouin scattering study. (jes)