Preparation of a Clay Composite Containing Poly(o-toluidine) and Halloysite, and Examining of Its Performance as a Humidity Sensor
Yıl 2021,
, 521 - 534, 25.04.2021
Meryem Kalkan Erdoğan
,
Meral Karakışla
Öz
This study outlines the production of an electrically conductive clay-based composite containing the halloysite as clay mineral and poly(o-toluidine) (POT) as a conductive filler. In the study, conductive POT/halloysite composite was obtained by in situ oxidative polymerization of o-toluidine using ammonium persulphate (APS) as an oxidant between the halloysite layers. By changing the polymerization conditions such as polymerization time, o-toluidine concentration, APS, and the concentration of HCl solution used as the reaction medium, the composite with the highest conductivity (7.5×10-5 S.cm-1) was obtained. Structural and morphological changes and thermal behaviors that occurred after the composite formation was revealed using various characterization techniques such as FTIR, XRD, TGA, and SEM. The usability of the prepared POT/halloysite composite as humidity sensing material was tested in comparison with the pure POT component of the composite at a relative humidity (% RH) varied between 41-94 (%). Accordingly, it was found that the composite exhibited a fairly regular resistance change to varying relative humidity compared to pure POT polymer.
Destekleyen Kurum
Ankara Üniversitesi Bilimsel Araştırma Projeleri
Proje Numarası
12B4240005
Teşekkür
The authors would like to thank the Ankara University Research Fund for financial support of this study.
Kaynakça
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Poli (o-toluidin) ve Halloysit İçeren Bir Kil Kompozitinin Hazırlanması ve Nem Sensörü Olarak Performansının İncelenmesi
Yıl 2021,
, 521 - 534, 25.04.2021
Meryem Kalkan Erdoğan
,
Meral Karakışla
Öz
Bu çalışma, kil minerali olarak halloysit ve iletken bir dolgu maddesi olarak poli (o-toluidin) (POT) içeren elektriksel olarak iletken kil bazlı bir kompozitin üretimini özetlemektedir. Çalışmada, iletken POT / halloysit kompoziti, o-toluidinin, halloysit tabakaları arasında oksidant olarak amonyum persülfat (APS) kullanılarak in-situ oksidatif polimerizasyon yöntemi ile elde edildi. Polimerizasyon süresi, o-toluidin derişimi, APS ve reaksiyon ortamı olarak kullanılan HCl çözeltisi derişimi gibi polimerizasyon koşulları değiştirilerek en yüksek iletkenliğe sahip kompozit (7.5×10-5 Scm-1) elde edildi. Kompozit oluşumundan sonra meydana gelen yapısal ve morfolojik değişiklikler ve termal davranışlar FTIR, XRD, TGA ve SEM gibi çeşitli karakterizasyon teknikleri kullanılarak ortaya konuldu. Hazırlanan POT / halloysit kompozitin nem algılama malzemesi olarak kullanılabilirliği, 41-94 arasında değişen bir bağıl nemde (% RH) kompozitin saf POT bileşeni ile karşılaştırılarak test edilmiştir. Buna göre kompozitin, saf POT polimere kıyasla değişen bağıl neme karşı oldukça düzenli bir direnç değişikliği sergilediği bulundu.
Proje Numarası
12B4240005
Kaynakça
- [1] L. F. B. L. Pontes, J. E. G. de Souza, A. Galembeck, and C. P. de Melo, “Gas sensor based on montmorillonite/polypyrrole composites prepared by in situ polymerization in aqueous medium,” Sensors and Actuators B: Chemical, vol. 177, pp. 1115-1121, 2013.
- [2] N. G. Duran, M. Karakışla, L. Aksu, and M. Saçak, “Conducting polyaniline/kaolinite composite: Synthesis, characterization and temperature sensing properties,” Materials Chemistry and Physics, vol. 118, no. 1, pp. 93-98, 2009, doi: https://doi.org/10.1016/j.matchemphys.2009.07.009.
- [3] F. Boran, S. Çetinkaya, M. Karakışla, and M. Saçak, “Synthesis and characterization of poly(o-toluidine)/kaolinite conductive composites for humidity and temperature sensing,” Pamukkale Üniversitesi Mühendislik Bilimleri Dergisi, vol. 24, no. 7, pp.1283-1278, 2018.
- [4] A. Verma and U. Riaz, “Sonolytically intercalated poly(anisidine-co-toluidine)/bentonite nanocomposites: pH responsive drug release characteristics,” Journal of Drug Delivery Science and Technology, vol. 48, pp.49-58, 2018, doi: https://doi.org/10.1016/j.jddst.2018.08.024.
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- [11] Q. Sheng, D. Zhang, Q. Wu, J. Zheng, and H. Tang, “Electrodeposition of Prussian blue nanoparticles on polyaniline coated halloysite nanotubes for nonenzymatic hydrogen peroxide sensing,” Analytical Methods, vol. 7, no. 16, pp.6896-6903, 2015, doi: 10.1039/C5AY01329A.
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- [21] T. Zhou, C. Li, H. Jin, Y. Lian, and W. Han, “Effective Adsorption/Reduction of Cr(VI) Oxyanion by Halloysite@Polyaniline Hybrid Nanotubes,” ACS Applied Materials & Interfaces, vol. 9, no. 7, pp.6030-6043, 2017, doi: 10.1021/acsami.6b14079.
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- [23] S. Zuo, W. Liu, C. Yao, X. Li, Y. Kong, X. Liu, H. Mao, and Y. Li, “Preparation of polyaniline–polypyrrole binary composite nanotube using halloysite as hard-template and its characterization,” Chemical engineering journal, vol. 228, pp.1092-1097, 2013.
- [24] S. I. A. Razak, N. F. A. Sharif, and I. I. Muhamad, “Polyaniline-coated halloysite nanotubes: effect of para-hydroxybenzene sulfonic acid doping,” Composite Interfaces, vol. 21, no. 8, pp.715-722, 2014, doi: 10.1080/15685543.2014.932551.
- [25] H. Parab, K. Chauhan, J. Ramkumar, R. D. P.S, N. S. Shenoy, and S. D. Kumar, “In-situ synthesised polyaniline - halloysite nanoclay composite sorbent for effective decontamination of nitrate from aqueous streams,” International Journal of Environmental Analytical Chemistry, pp.1-16, 2020, doi: 10.1080/03067319.2020.1828390.
- [26] M. M. Abolghasemi, N. Arsalani, V. Yousefi, M. Arsalani, and M. Piryaei, “Fabrication of polyaniline-coated halloysite nanotubes by in situ chemical polymerization as a solid-phase microextraction coating for the analysis of volatile organic compounds in aqueous solutions,” Journal of Separation Science, vol. 39, no. 5, pp.956-963, 2016, doi: https://doi.org/10.1002/jssc.201500839.
- [27] R. Surya Murali, M. Padaki, T. Matsuura, M. S. Abdullah, and A. F. Ismail, “Polyaniline in situ modified halloysite nanotubes incorporated asymmetric mixed matrix membrane for gas separation,” Separation and Purification Technology, vol. 132, pp.187-194, 2014, doi: https://doi.org/10.1016/j.seppur.2014.05.020.
- [28] M. V. Kulkarni, A. K. Viswanath, and P. K. Khanna, “Synthesis and humidity sensing properties of conducting poly(N-methyl aniline) doped with different acids,” Sensors and Actuators B: Chemical, vol. 115, no. 1, pp.140-149, 2006, doi: https://doi.org/10.1016/j.snb.2005.08.031.
- [29] C. Saravanan, S. Palaniappan, and F. Chandezon, “Synthesis of nanoporous conducting polyaniline using ternary surfactant,” Materials Letters, vol. 62, no. 6, pp.882-885, 2008, doi: https://doi.org/10.1016/j.matlet.2007.07.003.
- [30] P. S. Rao, D. N. Sathyanarayana, and S. Palaniappan, “Polymerization of Aniline in an Organic Peroxide System by the Inverted Emulsion Process,” Macromolecules, vol. 35, no. 13, pp.4988-4996, 2002, doi: 10.1021/ma0114638.
- [31] M. A. C. Mazzeu, L. K. Faria, M. R. Baldan, M. C. Rezende, and E. S. Gonçalves, “Influence of reaction time on the structure of polyaniline synthesized on a pre-pilot scale,” Brazilian Journal of Chemical Engineering, vol. 35, no. 1, pp.123-130, 2018.
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