Polipirol/Bentonit İletken Kompozitine Radyasyon Etkilerinin Araştırılması

Yıl 2012, Cilt: 7 Sayı: 2, 112 - 122, 06.12.2012

Orhan Karabulut Tahir Tilki Mustafa Yavuz Abdullah Kaplan Duygu Takanoğlu Mehmet Çabuk Seda Doğan

Öz

Bu çalışmada, polipirol/bentonit (PPy/Bnt) kompoziti, Bnt tabakaları arasında kimyasal oksidasyon polimerizasyonu yoluyla sentezlendi. Radyasyon uygulaması 60Co kaynağının kullanıldığı bir gama çemberi içerisinde hava ortamında gerçekleştirildi ve kompozite 40 kGy doz uygulandı. Kompozite radyasyon etkileri, FTIR, UV, TGA, XRD, SEM ve 290-410 K sıcaklık aralığında sıcaklığa bağlı elektriksel iletkenlik ölçümleri ile incelendi. Saf PPy/Bnt kompozitinin başlangıç bozunma sıcaklığı radyasyona uğramış PPy/Bnt kompozitinden daha yüksek olduğu bulundu. XRD desenlerine ait pik yoğunluğunun radyasyon ile değiştiği görüldü. Sıcaklığa bağlı iletkenlik ölçümlerinden radyasyonlanma sonucunda, PPy/Bnt kompozitin iletkenliğinin önemli ölçüde etkilediği gözlendi. İletkenlik sonuçları, hem saf PPy/Bnt hem de radyasyona uğramış kompozitlerde baskın iletim mekanizmasının Fermi seviyesi civarındaki seviyeler arasında hoplama yolu ile olduğu göstermiştir.

Anahtar Kelimeler

Polipirol, bentonit, iletken kompozit, gama radyasyonu

Investigation of Irradiation Effects on Conducting Composite of Polypyrole/Bentonite

Öz

In the present study, polypyrrole/bentonite (PPy/Bnt)
composite was synthesized into the Bnt interlayers by chemical oxidation
polymerization. The irradiation process was carried out in air in a
conventional gamma chamber, which uses a 60Co source, and the composite
was exposed to a dose of 40 kGy. Effects of irradiation on the composite
were investigated by means of FTIR, UV-visible absorption, TGA, XRD,
SEM and temperature dependent electrical conductivity in the temperature
range of 290-410 K. The initial decomposition temperature of pristine
PPy/Bnt composite was found higher than irradiated PPy/Bnt composite.
The XRD patterns revealed that the intensity of the peaks changed with
irradiation. It was found from temperature dependent conductivity
measurements that the radiation significantly influenced the
conductivity of PPy/Bnt composite. The conductivity results show that
dominant conduction mechanisms were hopping for both PPy/Bnt composite
and irradiated samples due to wide range of localized states present
near the Fermi level.

Anahtar Kelimeler

Polypyrrole, bentonite, conducting composite, gamma irradiation

Kaynakça

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• Mustafa Yavuz e-mail: [e-mail]
• Abdullah Kaplan e-mail: [e-mail]
• Orhan Karabulut e-mail: [e-mail]
• Tahir Tilki e-mail: [e-mail]
• Mehmet Çabuk e-mail: [e-mail]
• Duygu Takanoğlu email: [e-mail]
• Seda Doğan e-mail: [e-mail]