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

Diserahkan: 23 Oktober 2009 / Diterima: 11 Ogos 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

RUJUKAN

Ahmad, A., Lien, P.C. & Su’ait, M.S. 2010. Elektrolit Pepejal Polimer 49% Poli (Metil Metakrilat) Cangkukan Getah Asli - Litium Tetrafluoroborat. Sains Malaysiana 39: 65-71.

Aravindan, V., Laskmi, C. & Vickraman, P. 2009. Investigations on Na+ ion conducting polyvinylidenefluoride-co-hexafluoropropylene/poly ethylmethacrylate blend polymer electrolytes. Current Applied Physics 9: 1106-1111.

Baskaran, R., Selvasekarapandian, S., Hirankumar, G. & Bhuvaneswari, M.S. 2004. Vibrational, ac impedance and dielectric spectroscopic studies of poly(vinylacetate)–N,N–dimethylformamide–LiClO4 polymer gel electrolytes. Journal of Power Sources 134: 235-240.

Cao, J.–H., Zhu, B.–K. & Xu, Y.–Y. 2006. Structure and ionic conductivity of porous polymer electrolytes based on PVDF-HFP copolymer membranes. Journal of Membrane Science 281: 446-453.

Choi, B.K., Park, S.H., Joo, S.W. & Gong, M.S. 2004. Electrical and thermal properties of poly(vinylidene fluoride–hexafluoropropylene)-based proton conducting gel electrolytes. Electrochemica Acta 50: 649-652.

Fan, L., Dang, Z., Nan, C.W. & Li, M. 2002. Thermal, electrical and mechanical properties of plasticized polymer electrolytes based on PEO/P(VDF-HFP) blends. Electrochimica Acta 48: 205-209.

Hema, M., Selvasekerapandian, S., Sakunthala, A., Arunkumar, D. & Nithya, H. 2008. Sructural, vibrational and electrical characterization of PVA-NH4Br polymer electrolyte system. Physica B: Condensend Matter 403: 2740-2747.

Jeon, J.D., Kim, M.J. & Kwak, S.Y. 2006. Effects of addition of TiO2 nanoparticles on mechanical properties and ionic conductivity of solvent-free polymer electrolytes based on porous P(VdF-HFP)/P(EO-EC) membranes. Journal of Power Sources 162: 1304-1311.

Kim, K.M., Park, N.–G., Ryu, K.S. & Chang, S.H. 2006. Characteristics of PVdF-HFP/TiO2 composite membrane electrolytes prepared by phase inversion and conventional casting methods. Electrochimica Acta 51: 5636-5644.

Missan, H.P.S., Chu, P.P. & Sekhon, S.S. 2006. Ion conduction mechanism in non-aqueous polymer electrolytes based on oxalic acid: Effect of plasticizer and polymer. Journal of Power Sources 158: 1472–1479.

Noor, S.A.M., Ahmad, A. Talib, I.A. & Rahman, M.Y.A. 2010. Morphology, chemical interaction, and conductivity of a PEO-ENR50 based on solid polymer electrolyte. Ionics 16:161-170.

Ramya, C.S., Selvasekarapandian, S., Savitha, T., Hirankumar, G. & Angelo, P.C. 2007. Vibrational and impedance spectroscopic study on PVP–NH4SCN based polymer electrolytes. Physica B 393: 11-17.

Saikia, D., Chen-Yang, Y.W., Chen, Y.T., Li, Y.K. & Lin, S.I. 2008. Investigation of ionic conductivity of composite gel polymer electrolyte membranes based on P(VDF-HFP), LiClO4 and silica aerogel for lithium ion battery. Desalination 234: 24-32.

Saikia, D. & Kumar, A. 2004. Ionic conduction in P(VDF-HFP)/PVDF–(PC + DEC)–LiClO4 polymer gel electrolytes. Elecrochimica Acta 49: 2581-2589.

Singh, H.P. & Sekhon, S.S. 2003. Conductivity behaviour of proton conducting polymer gel electrolytes with PVdF-HFP. European Polymer Journal 39: 93-98.

Vijayakumar, G., Karthick, S.N., Sathiya Priya, A.R., Ramalingam, S. & Subramania, A. 2008. Effect of nanoscale CeO2 on PVDF-HFP based nanocomposites porous polymer electrolytes for Li–ion batteries. Journal Solid State Electrochemistry 12: 1135-1141.

*Pengarang untuk surat-menyurat; email: nsabirin@um.edu.my