Malaysian Journal of Analytical Sciences Vol 20 No 3 (2016): 687 - 696

DOI: http://dx.doi.org/10.17576/mjas-2016-2003-30

 

 

 

CRITICAL POWDER LOADING AND RHEOLOGICAL PROPERTIES OF POLYPROPYLENE/GRAPHITE COMPOSITE FEEDSTOCK FOR BIPOLAR PLATE APPLICATION

 

(Beban Serbuk Kritikal dan Sifat Reologi Bahan Suapan Komposit Polipropilena/Grafit untuk Aplikasi Plat Dwikutub)

 

Iswandi^1,2,3, Jaafar Sahari^1,2, Abu Bakar Sulong^1,2, Teuku Husaini¹*

 

¹Fuel Cell Institute

² Department Mechanical and Materials Engineering, Faculty of Engineering and Built Environment

Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia

³Department Mechanical Engineering,

Institut Teknologi Medan, Medan, Indonesia

 

*Corresponding author: t_husaini_st@yahoo.com

 

 

Received: 5 February 2016; Accepted: 22 April 2016

 

 

Abstract

Bipolar plate is one of the key parts in the fuel cell technology with the advantages of a higher electrical conductivity and mechanical properties are high. Injection molding is one of the manufacturing method that being used in the manufacture of bipolar plates. The critical powder loading and rheological properties of the feedstock are an important factor in the process of injection molding in the manufacturing process of bipolar plate.  The critical powder loading feedstocks with a mixture of polypropylene and graphite have been conducted with the torque method test. The appropriate critical powder loading the using a graphite filler material was produced with the composition of 75 % the weight of an optimum load and 25 % weight of polypropylene. The rheological studies have also been carried out using capillary test for determining critical loading powder by increasing the viscosity of the feedstock. The test results showed that the rheological properties of the feedstock with optimum powder loading to exhibit pseudoplastic properties are suitable for injection molding process with the n less than one.

 

Keywords:  injection molding, polymer composite, bipolar plate, fuel cell

 

Abstrak

Plat dwikutub adalah salah satu bahagian utama pada teknologi sel bahanapi dengan kelebihan sifat kekonduksian elektrik dan mekanik yang tinggi. Pengacuan suntikan adalah salah satu kaedah pembuatan yang digunakan dalam pembuatan plat dwikutub. Pembebanan serbuk genting dan sifat reologi bahan suapan adalah faktor penting dalam proses pengacuan suntikan semasa proses pembuatan plat dwikutub.  Pembebanan serbuk genting bahan suapan dengan campuran polipropilina dan grafit telah pun dijalankan dengan kaedah ujian nilai tork. Pembebanan serbuk genting yang sesuai menggunakan bahan suapan grafit telah dihasilkan dengan komposisi 75 % berat yang merupakan beban optimum dan 25 % berat polipropilena. Kajian reologi juga telah dijalankan menggunakan ujian rerambut bagi menentukan beban serbuk genting dengan peningkatan nilai kelikatan bahan suapan. Keputusan ujian sifat reologi didapati bahawa bahan suapan dengan beban serbuk optimal mempamerkan sifat pseudoplastik yang sesuai bagi proses pengacuanan suntikan dengan nilai n kurang daripada 1.  

 

Kata kunci:  pengacuan suntikan, komposit polimer, plat dwikutub, sel bahanapi

 

References

1.       Dicks, A. L. (2006). The role of carbon in fuel cells. Journal of Power Sources, 156(2): 128 – 141.

2.       Heo, S. I., Oh, K. S., Yun, J. C., Jung, S. H., Yang, Y. C., and Han, K. S. (2007). Development of preform moulding technique using expanded graphite for proton exchange membrane fuel cell bipolar plates. Journal of Power Sources, 171(2): 396 – 403.

3.       Dweiri, R. and Sahari, J. (2007). Electrical properties of carbon-based polypropylene composites for bipolar plates in polymer electrolyte membrane fuel cell (PEMFC). Journal of Power Sources, 171(2): 424 – 432.

4.       Liao, S. H., Yen, C. Y., Weng, C. C., Lin, Y. F., Ma, C. C. M., Yang, C. H., Tsai, M. C., Yen, M. Y., Hsiao, M. C., Lee, S. J., Xie, X. F. and Hsiao, Y. H. (2008). Preparation and properties of carbon nanotube/polypropylene nanocomposite bipolar plates for polymer electrolyte membrane fuel cells. Journal of Power Sources, 185(2): 1225 – 1232.

5.       Derieth, T., Bandlamudi, G., Beckhaus, P., Kreuz, C., Mahlendorf, F., and Heinzel, A. (2008). Development of highly filled graphite compounds as bipolar plate materials for low and high temperature PEM fuel cells. Journal of New Materials for Electrochemical Systems, 11(1): 21 – 29.

6.       Lee, J. H., Jang, Y. K., Hong, C. E., Kim, N. H., Li, P., and Lee, H. K. (2009). Effect of carbon fillers on properties of polymer composite bipolar plates of fuel cells. Journal of Power Sources, 193(2): 523 – 529.

7.       Guo, N., and Leu, M. C. (2012). Effect of different graphite materials on the electrical conductivity and flexural strength of bipolar plates fabricated using selective laser sintering. International Journal of Hydrogen Energy, 37(4): 3558 – 3566.

8.       Taherian, R., Golikand, A. N. and Hadianfard, M. J. (2011). The effect of mold pressing pressure and composition on properties of nanocomposite bipolar plate for proton exchange membrane fuel cell. Materials & Design, 32(7): 3883 – 3892.

9.       Planes, E., Flandin, L., and Alberola, N. (2012). Polymer composites bipolar plates for PEMFCs. Energy Procedia, 20: 311 – 323.

10.    Agote, I., Odriozola, A., Gutierrez, M., Santamarıa, A., Quintanilla, J., Coupelle, P. and Soares, J. (2001). Rheological study of waste porcelain feedstocks for injection moulding. Journal of the European Ceramic Society, 21(16), 2843 – 2853.

11.    Reddy, J. J., Ravi, N. and Vijayakumar, M. (2000). A simple model for viscosity of powder injection moulding mixes with binder content above powder critical binder volume concentration. Journal of the European Ceramic Society, 20(12): 2183 – 2190.

12.    Baojun, Z., Xuanhui, Q., and Ying, T. (2002). Powder injection molding of WC–8% Co tungsten cemented carbide. International Journal of Refractory Metals and Hard Materials, 20(5), 389 – 394.

13.    Krauss, V. A., Pires, E. N., Klein, A. N., and Fredel, M. C. (2005). Rheological properties of alumina injection feedstocks. Materials Research, 8(2): 187 – 189.

14.    Loh, N. H., Tor, S. B. and Khor, K. A. (2001). Production of metal matrix composite part by powder injection molding. Journal of Materials Processing Technology, 108(3): 398 – 407.

15.    Loebbecke, B., Knitter, R. and Haußelt, J. (2009). Rheological properties of alumina feedstocks for the low-pressure injection moulding process. Journal of the European Ceramic Society, 29(9): 1595 –1602.

16.    Mighri, F., Huneault, M. A. and Champagne, M. F. (2004). Electrically conductive thermoplastic blends for injection and compression molding of bipolar plates in the fuel cell application. Polymer Engineering & Science, 44(9): 1755 – 1765.

17.    Ahn, S., Park, S. J., Lee, S., Atre, S. V. and German, R. M. (2009). Effect of powders and binders on material properties and molding parameters in iron and stainless steel powder injection molding process. Powder Technology, 193(2): 162 – 169.

18.    Khakbiz, M., Simchi, A. and Bagheri, R. (2005). Analysis of the rheological behavior and stability of 316L stainless steel–TiC powder injection molding feedstock. Materials Science and Engineering: A, 407(1): 105 – 113.

19.    Hanemann, T. (2008). Influence of particle properties on the viscosity of polymer–alumina composites. Ceramics International, 34(8): 2099 – 2105.

20.    Wan, W., Yang, J., Zeng, J., Yao, L. and Qiu, T. (2014). Effect of solid loading on gelcasting of silica ceramics using DMAA. Ceramics International, 40(1): 1735 – 1740.

21.    Subbanna, M. and Kapur, P. C. (2002). Role of powder size, packing, solid loading and dispersion in colloidal processing of ceramics. Ceramics International, 28(4): 401 – 405.

22.    Jie, Z., Yan-wen, Z. O. U. and Jun, H. E. (2005). Influence of graphite particle size and its shape on performance of carbon composite bipolar plate. Journal of Zhejiang University Science A, 6(10): 1080 – 1083.

23.    Iswandi, Sahari, J. and Sulong, A. B. (2011, June). Effects of different particles sizes of graphite on the engineering properties of graphites/polypropylene composites on injection molding application. Key Engineering Materials, 471: 109 – 114.

24.    Thomas-Vielma, P., Cervera, A., Levenfeld, B. and Várez, A. (2008). Production of alumina parts by powder injection molding with a binder system based on high density polyethylene. Journal of the European Ceramic Society, 28(4), 763 – 771.

25.    Zakaria, H., Muhamad, N., Sulong, A. B. and Ibrahim, I. (2014). Moldability characteristics of 3 mol% yttria stabilized zirconia feedstock for micro-powder injection molding process. Sains Malaysiana, 43(1): 129 – 136.

26.    Kalyon, D. M., Birinci, E., Yazici, R., Karuv, B. and Walsh, S. (2002). Electrical properties of composites as affected by the degree of mixedness of the conductive filler in the polymer matrix. Polymer Engineering & Science, 42(7): 1609 – 1617.

27.    Karatas, C., Kocer, A., Ünal, H. I. and Saritas, S. (2004). Rheological properties of feedstocks prepared with steatite powder and polyethylene-based thermoplastic binders. Journal of Materials Processing Technology, 152(1): 77 – 83.

28.    German, R. M. and Bose, A. (1997). Injection molding of metal and ceramic. Metal Powder Industries Federation. New Jersey: John Wiley & Sons.

29.    Aggarwal, G., Smid, I., Park, S. J. and German, R. M. (2007). Development of niobium powder injection molding. Part II: Debinding and sintering. International Journal of Refractory Metals and Hard Materials, 25(3): 226 – 236.

30.    Olhero, S. M. and Ferreira, J. M. F. (2004). Influence of particle size distribution on rheology and particle packing of silica-based suspensions. Powder Technology, 139(1): 69 – 75.

31.    Han, C.D. (2007). Rheology and processing of polymeric materials. Polymer Processing, Vol. 2. Oxfort University Press.

32.    Trunec, M. and Hrazdera, J. (2005). Effect of ceramic nanopowders on rheology of thermoplastic suspensions. Ceramics International, 31(6): 845 – 849.

33.    Amin, S. Y. M., Muhamad, N., Jamaludin, K. R., Fayyaz, A. and Yunn, H. S. (2014). Characterization of the feedstock properties of metal injection-molded WC-Co with palm stearin binder system. Sains Malaysiana, 43(1), 123 – 128.

34.    Bobek, J., Seidl, M., Lenfeld, P., BČhálek, L. and Ausperger, A. (2011). Rheology of composites with nature vegetal origin fibers. International Journal of Mechanical, Aerospace, Industrial, Mechatronic and Manufacturing Engineering, 5(10): 1956 – 1959.

35.    Hassan, N., Ahmad, S., Muhamad, N., Omar, M. A. and Hassan, N. A. (2013). Thermoplastic natural rubber (TPNR) as a backbone polymer for metal injection molding. Sains Malaysiana, 42(12): 1787 –1791.