Influence of the processing conditions and corona poling on the morphology of /spl beta/-PVDF

The /spl alpha//spl rarr//spl beta/ phase transformation of PVDF through the stretching process at different temperatures was investigated. The optimum stretching conditions were studied and characterised by infrared spectroscopy and differential scanning calorimetry. The maximum /spl beta/-phase content was achieved at 80 /spl deg/C and a stretch ratio of 5. These samples were poled at several electric fields by the corona charge method. The effect of the electric field on the phase transformation was studied by infrared spectroscopy.