Sains Malaysiana 40(7)(2011): 707–712

Proton Conducting Polymer Electrolytes Based on PVDF-HFP and PVDF-HFP/PEMA Blend

(Elektrolit Polimer Pengkonduksi Proton berasaskan PVDF-HFP dan Adunan PVDF-HFP/PEMA)

S. Rudziah, N. Muda & S. Ibrahim

Institute of Graduate Studies, University of Malaya

50603 Kuala Lumpur, Malaysia

A. A. Rahman & N. S. Mohamed*

Center for Foundation Studies in Science, University of Malaya

50603 Kuala Lumpur, Malaysia

Received: 23 October 2009 / Accepted: 11 August 2010

ABSTRACT

In the present work, polymer electrolytes of poly(vinylidene fluoride co-hexafluoroproplyne) (PVDF-HFP) and PVDF-HFP/poly(ethyl methacrylate) (PVDF-HFP/PEMA) blend complexed with different concentrations of ammonium triflate (NH4CF3SO3) were prepared and characterized. The structural and thermal properties of the electrolytes were studied by XRD and DSC while the electrical properties were investigated by impedance spectroscopy. Ionic transference number measurements were done by D.C polarization technique. The results of these study showed that the PVDF-HFP/PEMA based electrolytes exhibit higher ionic conductivity as compared to PVDF-HFP based electrolytes. This could be attributed to the higher degree of amorphicity in the PVDF-HFP/PEMA based electrolytes. The results of ionic transference number measurements showed that the charge transport in these electrolytes was mainly due to ions and only negligible contribution comes from electrons.

Keywords: Amorphicity; ionic conductor; polymer blend; structural properties; thermal properties

ABSTRAK

Dalam penyelidikan ini, elektrolit polimer poli(vinilidin florida ko-heksafloropropilin) (PVDF-HFP) dan campuran PVDF-HFP/poli(etil metakrilat) (PEMA) dengan kepekatan amonium triflat yang berbeza telah disediakan dan dicirikan. Sifat-sifat struktur and terma elektrolit telah dikaji menggunakan pembelauan sinar-X dan analisis pengimbas kaloritmetri sementara sifat elektrik diukur menggunakan spektroskopi impedans. Pengukuran nombor permindahan ion telah dilakukan menggunakan teknik pengutuban A.T. Kajian menunjukkan bahawa elektrolit berasaskan PVDF-HFP/PEMA mempunyai kekonduksian ion yang lebih tinggi berbanding elektrolit berasaskan PVDF-HFP. Ini disebabkan oleh darjah amorfus yang lebih tinggi di dalam elektrolit berasaskan PVDF-HFP/PEMA. Keputusan pengukuran nombor pemindahan ion menunjukkan bahawa pengangkutan cas di dalam sistem ini disebabkan oleh ion-ion dengan sedikit sumbangan daripada elektron.

Kata kunci: Amorfus; campuran polimer; konduktor ionik; sifat struktur; sifat terma

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*Corresponding author; email: nsabirin@um.edu.my