Thermo-Oxidative Behavior of Carbon Black Composites for Self-Regulating Heaters

Abstract:

The composite materials for self-regulating heaters are conductive composites based on a polymer matrix and a dispersed conductive filler consisting in either carbon black or another carbon material, such as graphite or nanotubes. Similar materials are suitable for sensors and current limitations. As these materials used in heating applications work usually at elevated temperatures in presence of air, the ageing processes would be an important limiting factor of their lifetime. Therefore, thermal oxidation processes and crystallinity changes during the service of these products are of major interest in durability studies. The potential interference of carbon-based materials with the oxidation and ageing of polymer matrix shall be known in order to correctly estimate the durability of such materials. The effect of radiation exposure is studied taking into account the potential use of such materials in radiation environments. In this work, the activation energies of some initial, unaged and aged products at elevated temperatures are compared in order to characterize the effect of thermo-oxidative ageing and hence to evaluate their durability. The effect of some antioxidants is also discussed. The crystallinity, calculated from DSC was used for evaluation of the physical changes induced within the aged materials, following the procedures described in previous work. FTIR-ATR technique was used for characterization of chemical changes induced by ageing.

• Periodical: Advanced Engineering Forum (Volume 34)
• Pages: 66-80
• DOI: https://doi.org/10.4028/www.scientific.net/AEF.34.66
• Online since: October 2019
• Authors: Radu Setnescu, Marius Lungulescu, Adela Bara*, Alina Caramitu, Sorina Mitrea, Virgil Marinescu, Otilia Ana CULICOV
• Keywords: Activation Energy, Ageing, Electrically Conductive Composites, Self-Regulating Heaters, Thermo-Oxidation

References

[1] K. Makuuchi, S. Cheng, Radiation Processing of Polymer Materials and its Industrial Applications. John Wiley & Sons 2012, Ch 6.

[2] H. Chu, Z. Zhang, Y. Liu, J. Leng: Self-heating fiber reinforced polymer composite using meso/macropore carbon nanotube paper and its application in deicing. Carbon 66 (2014) 154-163.

DOI: 10.1016/j.carbon.2013.08.053

[3] R. Setnescu, A.R. Caramitu, M. Lungulescu, S. Mitrea, A. Bara, N. Stancu, Electroconductive composite presenting self-regulating temperature effect and process for making them. Patent application (RO) OSIM A/01053, 05.12.(2018).

[4] Y. Nakaramontri, C. Kummerlöwe, N. Vennemann, S. Wisunthorn, S. Pichaiyut, C. Nakason, Effect of bis(triethoxysilylpropyl) tetrasulfide (TESPT) on properties of carbon nanotubes and conductive carbon black hybrid filler filled natural rubber nanocomposites. eXPRESS Polymer Letters 12 (2018) 867–884.

DOI: 10.3144/expresspolymlett.2018.75

[5] L. Bokobza, Enhanced electrical and mechanical properties of multiwall carbon nanotube rubber composites, Polym. Adv. Technol 23 (2012) 1543–1549.

DOI: 10.1002/pat.3027

[6] L. Bokobza, Jean-Luc Bruneel, Michel Couzi, Raman Spectra of Carbon-Based Materials (from Graphite to Carbon Black) and of Some Silicone Composites, C 1 (2015), 77-94.

DOI: 10.3390/c1010077

[7] T. Zaharescu, S. Jipa, R. Setnescu, Celia Santos, B. Gigante, I. Mihalcea, C. Podina, L-M. Gorghiu, Thermal stability of additivated isotactic polypropylene. Polymer Bulletin 49 (2002) 289-296.

DOI: 10.1007/s00289-002-0098-8

[8] S. Jipa, T. Zaharescu, B. Gigante, C. Santos, R. Setnescu, T. Setnescu, M. Dumitru, L.M. Gorghiu, W. Kappel, I. Mihalcea, Chemiluminescence investigation of thermo-oxidative degradation of polyethylenes stabilized with fullerenes, Polym. Degrad. Stab. 80 (2003) 209–216.

DOI: 10.1016/s0141-3910(02)00392-0

[9] G. Prusty and S.K. Swain, Synthesis and characterization of conducting gas barrier polyacrylonitrile/graphite nanocomposites. Polym. Compos. 32 (2011) 1336–1342.

DOI: 10.1002/pc.21155

[10] A-R. Caramitu, R. Setnescu, M. Lungulescu, S. Mitrea, J. Pintea: Dielectric behaviour of some composite materials of HDPE/CB type. Electrotehnica, Electronica, Automatica (EEA) 66 (2018) 73-79.

[11] S. Ilie, R. Setnescu, Radiation Induced Aging Effects in Polymeric Cable Insulators at CERN, EDMS no 1055599 (2009).

[12] S. Ilie, R. Setnescu, E.M. Lungulescu, V. Marinescu, D. Ilie, T. Setnescu, G. Mares, Investigations of a mechanically failed cable insulation used in indoor conditions. Polymer Testing 30 (2010), 173 - 182.

DOI: 10.1016/j.polymertesting.2010.11.016

[13] G. Zerbi, G. Galiano, N.D. Fanti, L. Baini, Structural depth profiling in polyethylene films by multiple internal reflection infra-red spectroscopy. Polymer, 30 (1989) 2324 - 2327.

DOI: 10.1016/0032-3861(89)90269-3

[14] R. Setnescu, S. Jipa, T. Setnescu, W. Kappel, S. Kobayashi, Z. Osawa, Carbon 37 (1999) 1–6.

DOI: 10.1016/s0008-6223(98)00168-7

[15] F. Cataldo, The Role of Fullerene-Like Structures in Carbon Black and Their Interaction with Dienic Rubber, Fullerene Sci. Technol, 8 (2000) 105-112.

DOI: 10.1080/10641220009351401

[16] D. Xiang, L. Wang, Q. Zhang, B. Chen, Y. Li, E. Harkin-Jones, Comparative Study on the Deformation Behavior, Structural Evolution, and Properties of Biaxially Stretched High-Density Polyethylene/Carbon Nanofiller (Carbon Nanotubes, Graphene Nanoplatelets, and Carbon Black) Composites, Polymer Composites 2018 (2018) E909-E923.

DOI: 10.1002/pc.24328

[17] H.E. Kissinger, Reaction kinetics in differential thermal analysis. Anal. Chem. 29 (1957), 1702–1706.

DOI: 10.1021/ac60131a045

[18] M.J. Starink, A new method for the derivation of activation energies from experiments performed at constant heating rate, Thermochim Acta 288 (1996) 97–104.

DOI: 10.1016/s0040-6031(96)03053-5

[19] L. M. Dumitran, R. Setnescu, P. V. Notingher, L. V. Badicu, T. Setnescu, Method for lifetime estimation of power transformer mineral oil, Fuel 117 (2014) 756–762.

DOI: 10.1016/j.fuel.2013.10.002

[20] R. Setnescu, L. V. Badicu, L. M. Dumitran, P. V. Notingher, T. Setnescu, Thermal lifetime of cellulose insulation material evaluated by an activation energy based method, Cellulose (2014) 21:823–833.

DOI: 10.1007/s10570-013-0087-0

[21] E. Kovacs, Z. Wolkober, The Effect of the Chemical and Physical Properties of Carbon Black on the Thermal and Photooxidation of Polyethylene, J. Polym. Sci. Polym. Symp. 57 (1976) 171–180.

DOI: 10.1002/polc.5070570120

[22] W-K. Wong, Y. G. Hsuan, Interaction Between Carbon Black and Antioxidants in High-Density Polyethylene Pipe Resin, J. Transport. Res. Board 2310 (2012) 137-144.

DOI: 10.3141/2310-15

[23] P.D. Calvert, N.C. Billingham, Loss of additives from polymers: a theoretical model. J. Appl. Polym Sci. 24 (1979) 357–370.

DOI: 10.1002/app.1979.070240205

[24] E. Richaud, Kinetic modelling of phenols consumption during polyethylene thermal oxidation, Eur. Polym. J. 49 (2013) 2223–2232.

DOI: 10.1016/j.eurpolymj.2013.04.027

[25] A. Durmus, M. Woo, A Kaşgöz, C.W. Macosko, M Tsapatsis, Intercalated linear low density polyethylene (LLDPE)/clay nanocomposites prepared with oxidized polyethylene as a new type compatibilizer: Structural, mechanical and barrier properties. European Polymer Journal 43 (2007) 3737–3749.

DOI: 10.1016/j.eurpolymj.2007.06.019

[26] R.G. Alamo, W.W. Graessley, R. Krishnamoorti, D.J. Lohse, J.D. Londono, L. Mandelkern, et al, Small angle neutron scattering investigations of melt miscibility and phase segregation in blends of linear and branched polyethylenes as a function of the branch content, Macromolecules 30 (1997) 561–566.

DOI: 10.1021/ma961196j

[27] R.L. Blaine, H.E. Kissinger, Homer Kissinger and the Kissinger equation, Thermochimica Acta 540 (2012) 1– 6.

DOI: 10.1016/j.tca.2012.04.008

[28] S. Bădilescu, M. Giurginca, M. Toader, V. Tălpuș: IR Spectroscopy of Polymers and Additives. Ed. Tehnică, București (1982), Ch 5 (Roum.).

[29] J. Petrúj, J. Marchal, Mechanism of Ketone Formation in the Thermooxidation and Radiolytic Oxidation of Low-Density Polyethylene. Radiat. Phys. Chem. 16 (1980), 27-36.

DOI: 10.1016/0146-5724(80)90110-7