Effect of surface acoustic waves on curing of polyimide films

摘要

This paper presents the surface acoustic wave (SAW) mediated realignment for molecular orientation of polyimide films in curing process. The order parameters of polyimide films were obtained by measuring the anisotropic infrared absorbance using polarized infrared absorption spectroscopy. Experimental results of the double layered specimens indicated that the monomer chains were aligned to parallel to the wave fronts of SAW. The double layered specimens were made of a well cured polyimide film subsequently coated with the second film. The first film provides attractive forces to anchor the molecules of the second polyimide film on the first film. In the present experiments, the molecular orientation order parameter of SAW processed polyimide film is 0.23. It is between the values of unrubbed film (0.069) and rubbed one (0.535).