2062
J. Phys. Chem. 1984, 88, 2062-2067
Raman Spectroscopy in Polymeric Thin Film Optical Waveguides. 1. Polarized Measurements and Orientational Effects In Two-Dimensional Films N. E. Schlotter and J. F. Rabolt* IBM Research Laboratory, San Jose, California 95193 (Received: July 28, 1983)
Thin films of polymeric materials often show two-dimensional (2D) orientation depending on the conditions of sample preparation. This ordering has been studied by polarized Raman spectroscopy in which the incident laser light was coupled into thin, transparent films (1-4 pm) of semicrystalline and amorphous polymers deposited on Pyrex substrates forming an asymmetric slab waveguide. This experimental configuration allows propagation (in the waveguide) of modes with different incident polarizations and, in combination with polarization analysis of the scattered light, enables detection of anisotropic orientation in the film.
Introduction The use of vibrational spectroscopy to study polymers in either bulk or thin film form has provided much useful information about the structure and morphology of these materials. In particular, Raman scattering has helped elucidate conformational structure in oriented polymers by using the anisotropic scattering properties of uniaxially drawn filaments.’ Unfortunately, Raman measurements in thin films (
