Karbon Nanotüp Katkılı Levha Kalıplama Pestilinin AC Elektriksel İletkenliğinin ve Dielektrik Özelliklerinin İncelenmesi

Cam elyaf takviyeli ve doymamış polyester bazlı polimer kompozit malzemelerin iletkenlik ve dielektrik özelliklerini kontrol etmek için son yıllarda yaygın biçimde kullanılan karbon nanotüpler, yüksek potansiyelli materyallerdir. Bu çalışmada doymamış polyester bazlı standart levha kalıplama pestili (Sheet moulding compound/SMC) ve yüzde 1,2 oranında tek duvarlı karbon nanotüp (TDKN) ile katkılanmış malzeme için, kritik çalışma parametreleri olan AC elektriksel iletkenliği, dielektrik sabiti, dielektrik kayıp faktörü ve dielektrik dağılım faktörü (kayıp tanjant) değerleri karşılaştırmalı olarak analiz edilmiştir. 50 Hz ve 100 kHz frekans aralığında yapılan ölçümlerden elde edilen sonuçlar, karbon nanotüp katkısının yalıtkan olan malzemenin direncini önemli ölçüde azalttığını ve malzemenin AC iletkenliğini önemli ölçüde arttırdığını ortaya koymuştur. Aynı zamanda katkılı numune için iletkenliğin frekans değişiminden neredeyse bağımsız olduğu da sonuçlardan görülmektedir. Bununla birlikte dielektrik özelliklerin farklı polarizasyon etkileri nedeniyle frekansa bağlı davranış sergilediği ve artan frekans değerlerinde azalma eğilimi gösterdikleri bulunmuştur.

AC Electrical Conductivity and Dielectric Properties of Carbon Nanotube Reinforced Sheet Moulding Compound

Carbon nanotubes are high potential materials that have been widely used in recent years to control the conductivity and dielectric properties of glass fiber reinforced and unsaturated polyester-based polymer composite materials. AC electrical conductivity, dielectric constant, dielectric loss factor and dielectric dispersion factor (loss tangent) which are critical operating parameters were analyzed comparatively for the unsaturated polyester based standard sheet molding compound and its 1,2 percent single-walled carbon nanotube (SWCNT) reinforced version in this study. The results obtained from the measurements made in the frequency range of 50 Hz and 100 kHz revealed that the carbon nanotube addition significantly reduced the resistance of the insulating material and remarkably increased the AC conductivity of the material. It can also be seen from the results that the conductivity is almost independent of frequency variation. However, it has been found that dielectric properties of materials exhibit frequency-dependent behavior due to different polarization effects and tend to decrease at increasing frequency values.

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