Abstract
The effect of additives on paste rheology was investigated for preparation of porous ceramics with unidirectionally aligned cylindrical pores. Ammonium poly-carboxylic acid (APA) used as a dispersant and it was adsorbed on alumina powder surface. The adsorption isotherm of APA was fitted by Langmuir equation. The saturated monolayer adsorption was 5.9 mg/g. The apparent viscosity became a minimum at 0.8 mass % of APA corresponding to 71.2 mPa⋅s. This APA amount of 5.6 mg/g, is in good agreement with the observed APA amount. Since the nylon 66 fibers (0–35 vol. %) mixed with the alumina powder have a strong interaction with each other, they became twisted and agglomerated. This agglomeration increased with increasing fiber content but decreased by adding oleic acid. The pastes with added oleic acid were capable of being extruded at higher pressure. The obtained porous alumina ceramics showed highly oriented cylindrical pores parallel to the extrusion direction. The pore orientation was higher in the oleic acid added pastes than those without oleic acid. The added nylon 66 fibers are mostly converted to pores while maintaining the original shape after sintering. The pore size distribution of the obtained porous ceramics measured by mercury porosimetry method showed a peak at about 4 μm which is apparently smaller than that observed in the SEM photographs and the obtained result is considered to be corresponding to the necks formed by fiber contacts.
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References
1. M.G. Bader and J.F. Collins, in Fibre Sci. Technol. 18, 217 (1983).
2. L. Biolzi, L. Castellani, and I. Pitacco, J. Mater. Sci. 29, 2507 (1994).
3. K. Takahashi and N. S. Choi, J. Mater. Sci. 26, 4648 (1991).
4. S.K. De and V.M. Murty, Polym. Eng. Reviews 4, 313 (1984).
5. J.K. Kim and S.H. Park, J. Mater. Sci. 35, 1069 (2000).
6. J.L. Thomason and M.A. Vlug, Composites Part A, 27, 477 (1996).
7. T. Akatsu, Y. Tanabe, Y. Matsuo, and E. Yasuda, J. Ceram. Soc. Jpn. 100, 1297 (1992).
8. S. Blackburn and H. Böhm, J. Mater. Sci. 10, 2481 (1995).
9. Y. Shao, S. Marikunte, and S.P. Shah, Conc. Int. 17, 48 (1995).
10. H. Takashima, K. Miyagai, T. Hashida, and V.C. Li, Eng. Frac. Mech. 70, 853 (2003).
11. T. Isobe, T. Tomita, Y. Kameshima, A. Nakajima, and K. Okada, J. Eur. Ceram. Soc. 26, 957 (2006).
12. T. Isobe, Y. Kameshima, A. Nakajima, K. Okada, and Y. Hotta, J. Eur. Ceram. Soc., in press.
13. B.A. Knutsson, J.L. White, and K.B. Abbas, J. Appl. Polym. Sci. 26, 2347 (1981).
14. S. Thomas, G. Kalaprasad, G. Mathew, and C. Pavithran, J. Appl. Polym. Sci. 89, 432 (2003).
15. J. Thomasset, P.J. Carreau, B. Sanschagrin, and G. Ausias, J. Non-Newtonian Fluid Mech. 125, 25 (2005).
16. M.L. Becraft and A.B. Metzner, J. Rheol. 36, 143 (1992).
17. I.J. Langmuir, J. Chem. Soc. 111, 1361 (1918).
18. M.G. Bader and J.F. Collins, in Fibre science and technology 18, 217 (1983).
19. L. Biolzi, L. Castellani, and I. Pitacco, Journal of materials science 29, 2507 (1994).
20. K. Takahashi and N. S. Choi, Journal of materials science 26, 4648 (1991).
21. S.K. De and V.M. Murty, Polymer engineering reviews 4, 313 (1984).
22. J.K. Kim and S.H. Park, Journal of materials science 35, 1069 (2000).
23. J.L. Thomason and M.A. Vlug, Composites Part A, 27, 477 (1996).
24. T. Akatsu, Y. Tanabe, Y. Matsuo, and E. Yasuda, Journal of the Ceramic Society of Japan 100, 1297 (1992).
25. S. Blackburn and H. Böhm, Journal of materials research 10, 2481 (1995).
26. Y. Shao, S. Marikunte, and S.P. Shah, Concrete international 17, 48 (1995).
27. H. Takashima, K. Miyagai, T. Hashida, and V.C. Li, Engineering fracture mechanics 70, 853 (2003).
28. T. Isobe, T. Tomita, Y. Kameshima, A. Nakajima, and K. Okada, Journal of the European Ceramic Society, in press.
29. T. Isobe, Y. Kameshima, A. Nakajima, K. Okada, and Y. Hotta, Journal of the European Ceramic Society, in press.
30. B.A. Knutsson, J.L. White, and K.B. Abbas, Journal of applied polymer science 26, 2347 (1981).
31. S. Thomas, G. Kalaprasad, G. Mathew, and C. Pavithran, Journal of applied polymer science 89, 432 (2003).
32. J. Thomasset, P.J. Carreau, B. Sanschagrin, and G. Ausias, Journal of non-newtonian fluid mechanics 125, 25 (2005).
33. M.L. Becraft and A.B. Metzner, Journal of Rheology 36, 143 (1992).
34. I.J. Langmuir, Journal of the Chemical Society 111, 1361 (1918).
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Isobe, T., Kameshima, Y., Nakajima, A. et al. Effect of dispersant on paste rheology in preparation of porous alumina with oriented pores by extrusion method. J Porous Mater 13, 269–273 (2006). https://doi.org/10.1007/s10934-006-8015-4
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DOI: https://doi.org/10.1007/s10934-006-8015-4