Sains Malaysiana 42(4)(2013): 481–485

Properties of ENR-50 Based Electrolyte System

(Sifat Sistem Elektrolit Berasaskan ENR-50)

N. Zainal* & N.S. Mohamed

Centre for Foundation Studies in Science, University of Malaya, 50603 Kuala Lumpur

Malaysia

N. Zainal*

Institute of Graduate Studies, University of Malaya, 50603 Kuala Lumpur, Malaysia

R. Idris

Advanced Materials Research Centre, SIRIM Berhad , 09000 Kulim Kedah, Malaysia

Diserahkan: 15 Jun 2011 / Diterima: 7 Mac 2012

ABSTRACT

In this work, epoxidized natural rubber 50 (ENR-50) has been used as a host polymer for the preparation of electrolyte system. Attenuated total reflection-fourier transform infrared spectroscopic analyses showed the presence of lithium salt-ENR interactions. The glass transition temperature displayed an increasing trend with the increase in salt concentration indicating that the ionic conductivity was not influenced by segmental motion of the ENR-50 chains. The increase in glass transition temperature with the addition of salt was due to the formation of transient cross-linking between ENR-50 chains via the coordinated interaction between ENR-50 chains and salt. The highest room temperature ionic conductivity obtained was in the order of 10-5 S cm-1 for the film containing 50 wt% of lithium salt. The ionic conductivity of this electrolyte system increased with increasing temperature and obeyed the Vogel-Tamman-Fulcher behavior. The increase in ionic conductivity of the electrolyte system with salt concentration could also be correlated to the charge carriers concentration and/or migration rate of charge carriers.

Keywords: Activation energy; conductivity; ENR-50; VTF

ABSTRAK

Dalam kajian ini, getah asli terepoksi 50 (ENR-50) digunakan sebagai polimer perumah untuk penyediaan sistem elektrolit. Analisis menggunakan spektroskopi inframerah menunjukkan terdapat interaksi garam litium dengan ENR. Suhu peralihan kaca meningkat dengan penambahan kepekatan garam yang menunjukkan bahawa kekonduksian ion tidak dipengaruhi oleh pergerakan segmen rantai ENR-50 itu. Kenaikan suhu peralihan kaca dengan penambahan garam mungkin disebabkan oleh pembentukan hubungan silang sementara rantai ENR-50 melalui interaksi antara rantai ENR-50 dan garam. Kekonduksian ion tertinggi yang diperoleh adalah dalam tertib 10-5 S sm-1 bagi filem yang mengandungi 50% berat garam litium. Kekonduksian ion bagi sistem elektrolit ini meningkat dengan penambahan suhu dan mematuhi perlakuan Vogel-Tamman-Fulcher. Penambahan kekonduksian ion bagi sistem elektrolit ini dengan kepekatan garam juga boleh dihubungkan dengan kepekatan pembawa cas dan/atau kadar pemindahan cas.

Kata kunci: ENR-50; kekonduksian; tenaga pengaktifan; VTF

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