Effect of local structure of MnCl2-Filled PVDF films on their optical, electrical, electron spin resonance, and magnetic properties

The filling level (W ) dependence of the local structure of MnCl2 through the PVDF matrix was explored. The presence of a- and b-PVDF crystalline phases were detected by X-ray diffraction, and it was confirmed by the infrared (IR) absorption spectra. A significant head-to-head content was implied by IR spectroscopy. Two filling, level-dependent optical energy gaps were found through the UV-VIS spectral investi- gation. An intrachain one-dimensional interpolaron hopping mechanism was assumed to proceed in the temperature range of 350-375 K. The calculated values of the charge carrier hopping distance were in the range of 6.5-9.7 nm. The temperature dependence of the direct current (dc) magnetic susceptibility exhibited a Curie-Weiss behavior. Positive values of the paramagnetic Curie temperature (up) for W up to 14.5% indicated the presence of a ferromagnetic interaction, while negative up obtained for higher W values suggested an antiferromagnetic interaction at lower temperature. The electron spin resonance (ESR) analysis revealed the existance of both isolated and aggregated Mn 2/ ions within the PVDF matrix. q 1998 John Wiley & Sons, Inc. J Appl Polym Sci 70: 1437-1445, 1998