Effect of Carbon Black Surface Treatment on the AC Electrical Properties of PP-Based Composites

2013 ◽  
Vol 712-715 ◽  
pp. 182-189
Author(s):  
Nai Xiu Ding ◽  
Li Li Wang ◽  
Pei Yan Zuo ◽  
Yong Li ◽  
Guang Ye Liu

Carbon black was first activated by grafting and coupling respectively. Then the grafted carbon black, coupled carbon black, together with the unmodified carbon black was filled into polypropylene to prepare three kinds of composites respectively. The measurements of Fourier Transform Infrared Spectroscopy (FTIR) and alternating current (AC) electrical properties were performed on the composites. And the effect of CB activation on the AC electrical properties was analyzed. Seen from the result of FTIR spectra it can be found that different groups are bonded to the surface of carbon black after activation. For the corresponding conductive composites,it was found that the value of percolation threshold decreases and the electrical conductivity improves consequently after the carbon black activation. The influence of carbon black activation on the AC electrical properties of the composites and their variation with frequency was analyzed. The AC conduction mechanism was discussed and the conduction model was constructed based on the analysis.

2012 ◽  
Vol 217-219 ◽  
pp. 644-651
Author(s):  
Nai Xiu Ding ◽  
Li Li Wang ◽  
Mao Sheng Zhan ◽  
Liang Liu ◽  
Shuai Feng Xu

In this paper, Carbon black was activated using titanate-type coupling agent, and then filled into polypropylene to prepare conductive composites, whose alternating current (AC) electrical properties, including impendence Z, phase angel θ, dielectric constantε and dissipation factor tgδ that is a function of frequency and carbon black concentration were investigated by AC impedance spectroscopy. The percolation threshold of 5wt% carbon black concentration was obtained from the experimental result of volume resistivity for the conductive composites. It was found that the variation of AC electrical properties, which is a function of frequency, was dramatic and dependent on the filler concentration. It was also found that dependence of the real and the imaginary parts of impendence on frequency decreased with the increased concentration of carbon black, while the phase angle, dielectric constant and dissipation factor increased. The AC electrical properties were given based on the conductive network model and the corresponding equivalent circuit were concluded


Nanomaterials ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 3103
Author(s):  
Valentina Brunella ◽  
Beatrice Gaia Rossatto ◽  
Domenica Scarano ◽  
Federico Cesano

Polyamide 66 (PA66) is a well-known engineering thermoplastic polymer, primarily employed in polymer composites with fillers and additives of different nature and dimensionality (1D, 2D and 3D) used as alternatives to metals in various technological applications. In this work, carbon black (CB), a conductive nanofiller, was used to reinforce the PA66 polymer in the 9–27 wt. % CB loading range. The reason for choosing CB was intrinsically associated with its nature: a nanostructured carbon filler, whose agglomeration characteristics affect the electrical properties of the polymer composites. Crystallinity, phase composition, thermal behaviour, morphology, microstructure, and electrical conductivity, which are all properties engendered by nanofiller dispersion in the polymer, were investigated using thermal analyses (thermogravimetry and differential scanning calorimetry), microscopies (scanning electron and atomic force microscopies), and electrical conductivity measurements. Interestingly, direct current (DC) electrical measurements and conductive-AFM mapping through the samples enable visualization of the percolation paths and the ability of CB nanoparticles to form aggregates that work as conductive electrical pathways beyond the electrical percolation threshold. This finding provides the opportunities to investigate the degree of filler dispersion occurring during the transformation processes, while the results of the electrical properties also contribute to enabling the use of such conductive composites in sensor and device applications. In this regard, the results presented in this paper provide evidence that conductive carbon-filled polymer composites can work as touch sensors when they are connected with conventional low-power electronics and controlled by inexpensive and commercially available microcontrollers.


2013 ◽  
Vol 712-715 ◽  
pp. 175-181 ◽  
Author(s):  
Nai Xiu Ding ◽  
Li Li Wang ◽  
Pei Yan Zuo ◽  
Yong Li ◽  
Guang Ye Liu

Carbon black was activated and then filled into polypropylene to prepare conductive composites, of which the electrical properties, including impedance Z, phase angelθ and dissipation factor tgδ, as a function of frequency and carbon black concentration were investigated using impedance analyzer. The percolation threshold of 5wt% carbon black concentration was obtained. It was found that the variation of AC electrical properties as a function of frequency is dramatic and dependent on the carbon black concentration. It was also found that dependence of the real part and the imaginary part of impedance on frequency decreases with the increased concentration of carbon black, while that of phase angle and dissipation factor increases. Based on the corresponding results, the conductive network model and the corresponding equivalent circuit were constructed.


2002 ◽  
Vol 75 (4) ◽  
pp. 691-700 ◽  
Author(s):  
Dana Pantea ◽  
Hans Darmstadt ◽  
Serge Kaliaguine ◽  
Silvia Blacher ◽  
Christian Roy

Abstract The surface morphology of various carbon blacks was studied by low-pressure nitrogen adsorption. The shape of their low-pressure nitrogen isotherm depends on the concentration of surface defects. This defect concentration on the surface is different for thermal blacks, even for those of the same grade. Different surface morphologies were also observed for carbon blacks obtained by pyrolysis of truck tires. The concentration of defects increased with pyrolysis pressure. For the various furnace blacks, however, similar surface morphologies were observed. The electrical conductivity of thermal and pyrolytic carbon blacks decreases with increasing defect concentration. However, in spite of a similar surface morphology, different conductivities were observed for furnace blacks. The carbon black surface morphology is therefore not a determining factor for the electrical conductivity. Furthermore, the graphitic character of the carbon black surface was studied by secondary ion mass spectroscopy (SIMS). For thermal, furnace and pyrolytic carbon blacks, the conductivity increased with increasing graphitic character of the carbon black surface, thus underlining the importance of this parameter.


1968 ◽  
Vol 41 (2) ◽  
pp. 382-399 ◽  
Author(s):  
Marvin L. Deviney ◽  
Lawrence E. Whittington

Abstract Radiotracer techniques have been applied to the study of interactions of carbon black surface functional groups with two chosen organic systems. The basic reaction mechanisms demonstrated in this study may have implications in elastomer reinforcement. Direct radiochemical evidence supports the conclusions of Hallum and Drushel (based on less direct polarographic data) that surface quinonic groups exhibit hydrogen abstraction activity toward tertiary hydrogens in paraffinic hydrocarbons. Studies on the system carbon black and styrene using tritium radiotracer have provided direct evidence that phenolic hydrogens participate in the polymerization acceleration and graft polymer formation reaction and are transferred to the growing polystyrene chains as postulated by Donnet. Several methods have been developed for specifically labelling certain oxygenated functional groups on the carbon surface with tritium and for tritium labelling carbon black in aromatic hydrogen positions. The techniques developed in this work and the basic reaction mechanisms derived will permit this investigation to be extended into a radiochemical study of carbon black surface interactions with elastomer related systems of interest to the rubber industry.


Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 153
Author(s):  
Sang-Min Lee ◽  
Sang-Hye Lee ◽  
Jae-Seung Roh

In the present study, carbon black activated by CO2 gas was examined through XRD analysis, especially with regard to changes in its structural parameters. Based on the results, its activation process was thoroughly analyzed. The activation process was controlled by isothermally activating the carbon black inside a reaction tube through which CO2 gas flowed. With this approach, the degree of activation was varied as desired. At an early stage of the activation process, the amorphous fraction on the carbon black surface was preferentially activated, and later the less-developed crystalline carbon (LDCC) region inside the carbon black particles started to be activated. The latter process was attributable to the formation of pores inside the carbon black particles. As the activation process proceeded further, the more-developed crystalline carbon (MDCC) region started to be activated, thereby causing the pores inside the carbon black particles to grow larger. At the last stage of the activation process, La was found to be decreased to about 40 Å. This implied that the edges of the graphite crystals had been activated, thus causing the internal pores to grow and coalesce into larger pores. Activated conductive Super-P with enhanced pore properties is expected to have wide applications.


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