Sains Malaysiana 40(7)(2011): 691–694

Conductivity and Structural Studies of Plasticized Polyacrylonitrile (PAN) – Lithium Triflate Polymer Electrolyte Films

(Kekonduksian dan Struktur Filem Elektrolit Polimer Poliakrilonitril (PAN) – Litium Triflat yang Mengandungi Agen Pemplastik)

A. Ahmad, K.B. Md. Isa & Z. Osman*

Physics Department, University of Malaya, 50603 Kuala Lumpur, Malaysia

Received: 23 October 2009 / Accepted: 20 September 2010

ABSTRACT

The effect of different plasticizers on the properties of PAN– polymer electrolytes has been studied. Propylene carbonate (PC) and ethylene carbonate (EC) having different values of donor numbers, dielectric constant and viscosity have been used as plasticizers. The highest room temperature conductivity for the film in the PAN– system was 3.04 × 10-4 S cm-1. The highest room temperature conductivity for the films in the PAN–EC– system and the PAN–PC– system was 1.32 × 10-3 and 8.64 × 10-4 S cm-1. The addition of plasticizers has been found to enhance the conductivity of polymer electrolytes by increasing the amorphous content as well as by dissociating the ion aggregates present in polymer electrolyte. Conductivity temperature-dependence studies of these plasticized PAN-salt systems were carried out in the temperature range of 303 to 373 K. The conductivity versus temperature plots obeyed an Arrhenius type variation. The structural and complex formations were studied by X-ray diffraction (XRD) and Fourier Transform Infrared (FTIR) spectroscopy.

Keywords: Conductivity; lithium triflate; plasticizer; polyacrylonitrile; polymer electrolytes

ABSTRAK

Kesan penggunaan agen pemplastik yang berbeza terhadap sifat elektrolit polimer PAN– telah dikaji. Propilina karbonat (PC) and etilena karbonat (EC) mempunyai bilangan penderma, pemalar dielektrik dan kelikatan yang berbeza digunakan sebagai agen pemplastik. Nilai kekonduksian tertinggi pada suhu bilik bagi filem dalam sistem PAN– adalah 3.04 × 10-4 S cm-1. Nilai kekonduksian tertinggi pada suhu bilik bagi filem dalam sistem PAN–EC– dan sistem PAN–PC– adalah 1.32 × 10-3 dan 8.64 × 10-4 S cm-1. Penambahan agen pemplastik didapati telah meningkatkan nilai kekoduksian elektrolit polimer melalui peningkatan kandungan amorfus dan penguraian kelompok ion yang wujud. Kajian kekonduksian terhadap suhu untuk sistem PAN-garam yang mengandungi agen pemplastik dilakukan pada julat suhu daripada 303 hingga 353 K. Plot bagi kekonduksian melawan suhu didapati mengikut Arrhenius. Struktur dan pembentukan kompleks dikaji dengan menggunakan pembelauan sinar-X (XRD) dan Spektroskopi Infra-merah (FTIR).

Kata kunci: Agen pemplastik; elektrolit polimer; kekonduksian; litium triflat; poliakrilonitril

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