Sains Malaysiana 40(1)(2011): 75–78

Ion Conductive Polymer Electrolyte Membranes and Simulation of Their Fractal Growth Patterns

(Membran Polimer Elektrolit Konduksian Ion dan Simulasi Pola-pola Pertumbuhan Fraktal)

S. Amir^1, *, S.A. Hashim Ali² & N.S. Mohamed¹

¹Pusat Asasi Sains, University of Malaya

50603 Kuala Lumpur, Malaysia

²Institute of Mathematical Sciences, Faculty of Science

University of Malaya, 50603 Kuala Lumpur, Malaysia

Diserahkan: 7 Disember 2009 / Diterima: 15 Julai 2010

ABSTRACT

Due to their high ionic conductivity, solid polymer electrolyte (SPE) systems have attracted wide spread attention as the most appropriate choice to fabricate all-solid-state electrochemical devices, namely batteries, sensors and fuel cells. In this work, ion conductive polymer electrolyte membranes have been prepared for battery fabrication. However, fractals were found to grow in these polymer electrolyte membranes weeks after they were prepared. It was believed that the formation of fractal aggregates in these membranes were due to ionic movement. The discovery of fractal growth pattern can be used to understand the effects of such phenomenon in the polymer electrolyte membranes. Digital images of the fractal growth patterns were taken and a simulation model was developed based on the Brownian motion theory and a fractal dialect known as L-system. A computer coding has been designed to simulate and visualize the fractal growth.

Keywords: Fractal; polymer electrolytes; simulation

ABSTRAK

Disebabkan kekonduksian ionik yang tinggi, sistem polimer elektrolit pepejal (SPE) telah menarik perhatian meluas sebagai pilihan paling sesuai untuk memfabrikasi alat elektrokimia keadaan pepejal sepenuhnya, iaitu bateri, pengesan dan sel bahan bakar. Dalam kerja penyelidikan ini, membran polimer elektrolit konduksian ion telah disediakan untuk penyediaan bateri. Bagaimanapun, fraktal telah didapati tumbuh dalam membran polimer elektrolit ini beberapa minggu selepas disediakan. Adalah dipercayai pembentukan agregat fraktal dalam membran ini ialah disebabkan oleh pergerakan ion. Penemuan corak pertumbuhan fraktal boleh digunakan bagi memahami kesan fenomena pergerakan ion dalam membran polimer elektrolit. Imej-imej digital pola-pola pertumbuhan fraktal telah diambil dan satu model simulasi dibangunkan berasaskan teori pergerakan Brown dan dialek fractal dikenali sebagai L-sistem. Pengekodan komputer telah direkabentuk bagi mensimulasi dan menggambarkan pertumbuhan fraktal.

Kata kunci: Elektrolit polimer; fraktal; simulasi

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