Ionic conduction and dielectric dispersion study on chain dynamics of poly(vinyl pyrrolidone)-glycerol blends

Dielectric behaviOL11- 01' "IaSS401-11)er polymer blends i.e. poly(vinyl pyri-olidone) (PVP) (avera,ge inole-lal- Wei- -'ht M%v= 24000, 40000 and 360000 g inol-1) will' 111yeerol (Gly) Ul) to 30 %vt % PVP has been investigated in the t'l-CCILICI)CY 1"an"e 20 Hz-1 MHz at 25T. 'rbe frequency dependent complex dielectric constant of the PVP-Gly blends indicates the relaxation process caused by the micro-Brownian chain motion of the PVP in the fl-eClUency range 10 kHz- I MHz. The valUCS of' dielectric relaxation stren-th and relaxation time for this process were determined to explore the concentration and chain len-th effect oil the relaxation process. The ac coll(ILICtiVity valLies were fOUnd correSpOildin" to dC COndUCtiVity at fi-CCILIenCieS lO%VCi- than 10 kHz. The loss part ofelectric modUILIS exhibits a peak in the frequency range 10 kHz - 40 kHz, which corresponds to the ionic condUCtiVity relaxation. The complex impedance plane plots of PVP-Gly blends confirm the contribUtiOn of' the electrode SLH-faCe P01,11-iZatiOn effCCt Oil tile dielectric constant valLies at fi-eqLlCiicies lower than 200 Hz. FUrther, the results ofthe dielectric dispersion of the PVP-Gly blends were compared with the dielectric dispersion of poly(vinyl pyri-olidonc)-ethylene glycol oligoiners (PVP--EG0s) blends [Shinyashiki et al., 2006] to confirin the effect Of 111-linber of' hydroxyl proups ofthe solvent 11101CCUIeS Oil the hetero-eneOLIS hydrogen bond complex formation in these blends.