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Federico Carpi - One of the best experts on this subject based on the ideXlab platform.
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Active Compression Bandage Made of Electroactive Elastomers
IEEE ASME Transactions on Mechatronics, 2018Co-Authors: Luigi Calabrese, Gabriele Frediani, Danilo De Rossi, Federico CarpiAbstract:Active compression bandages made of electromechanically active Elastomers have recently been proposed to counteract dynamically, rather than statically, limb swelling due to various pathologies or conditions. To apply and modulate the compression pressure they exploit the ability of electroactive Elastomer layer/s of changing size in response to a high voltage. For safety reasons, such devices must be properly insulated from the user limb. In this paper, we present an electroactive bandage made of two prestretched layers of an electroactive Acrylic Elastomer sandwiched between two insulating layers of a passive silicone Elastomer. Moreover, uniaxial stiffening elements where introduced to maximize actuation along the radial direction. Prototypes of the bandage were tested with a pressurized air chamber, which mimicked the compliance of a human limb. Both experimental investigations and a finite electroelasticity analytical model showed that the passive layers play a key role for an effective transmission of actuation from the active layers to the load. The prototypes were able to actively vary the applied pressure up to 10%. The model showed that by increasing the number of electroactive layers the pressure variation could be further increased, although with a saturation trend, providing a useful indication for future designs of such bandages.
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ultrafast all polymer electrically tunable silicone lenses
Advanced Functional Materials, 2015Co-Authors: Luc Maffli, Michele Ghilardi, Federico Carpi, Samuel RossetAbstract:Dielectric Elastomer actuators (DEA) are smart lightweight flexible materials integrating actuation, sensing, and structural functions. The field of DEAs has been progressing rapidly, with actuation strains of over 300% reported, and many application concepts demonstrated. However many DEAs are slow, exhibit large viscoelastic drift, and have short lifetimes, due principally to the use of Acrylic Elastomer membranes and carbon grease electrodes applied by hand. Here a DEA-driven tunable lens, the world's fastest capable of holding a stable focal length, is presented. By using low-loss silicone Elastomers rather than Acrylics, a settling time shorter than 175 μs is obtained for a 20% change in focal length. The silicone-based lenses show a bandwidth 3 orders of magnitude higher compared to lenses of the same geometry fabricated from the Acrylic Elastomer. Stretchable electrodes, a carbon black and silicone composite, are precisely patterned by pad-printing and subsequently cross-linked, enabling strong adhesion to the Elastomer and excellent resistance to abrasion. The lenses operate for over 400 million cycles without degradation, and show no change after more than two years of storage. This lens demonstrates the unmatched combination of strain, speed, and stability that DEAs can achieve, paving the way for complex fast soft machines.
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ultrafast all polymer electrically tunable silicone lenses
Advanced Functional Materials, 2015Co-Authors: Luc Maffli, Michele Ghilardi, Federico Carpi, Samuel Rosset, Herbert SheaAbstract:Dielectric Elastomer actuators (DEA) are smart lightweight flexible materials integrating actuation, sensing, and structural functions. The field of DEAs has been progressing rapidly, with actuation strains of over 300% reported, and many application concepts demonstrated. However many DEAs are slow, exhibit large viscoelastic drift, and have short lifetimes, due principally to the use of Acrylic Elastomer membranes and carbon grease electrodes applied by hand. Here a DEA-driven tunable lens, the world's fastest capable of holding a stable focal length, is presented. By using low-loss silicone Elastomers rather than Acrylics, a settling time shorter than 175 μs is obtained for a 20% change in focal length. The silicone-based lenses show a bandwidth 3 orders of magnitude higher compared to lenses of the same geometry fabricated from the Acrylic Elastomer. Stretchable electrodes, a carbon black and silicone composite, are precisely patterned by pad-printing and subsequently cross-linked, enabling strong adhesion to the Elastomer and excellent resistance to abrasion. The lenses operate for over 400 million cycles without degradation, and show no change after more than two years of storage. This lens demonstrates the unmatched combination of strain, speed, and stability that DEAs can achieve, paving the way for complex fast soft machines.
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Electrical breakdown of an Acrylic dielectric Elastomer: effects of hemispherical probing electrode’s size and force
Taylor & Francis Group, 2015Co-Authors: Bin Chen, Matthias Kollosche, Mark Stewart, James Busfield, Federico CarpiAbstract:Dielectric Elastomers are widely investigated as soft electromechanically active polymers (EAPs) for actuators, stretch/force sensors, and mechanical energy harvesters to generate electricity. Although the performance of such devices is limited by the dielectric strength of the constitutive material, the electrical breakdown of soft Elastomers for electromechanical transduction is still scarcely studied. Here, we describe a custom-made setup to measure electrical breakdown of soft EAPs, and we present data for a widely studied Acrylic Elastomer (VHB 4905 from 3M). The Elastomer was electrically stimulated via a planar and a hemispherical metal electrode. The breakdown was characterized under different conditions to investigate the effects of the radius of curvature and applied force of the hemispherical electrode. With a given radius of curvature, the breakdown field increased by about 50% for a nearly 10-fold increase of the applied mechanical stress, while with a given mechanical stress the breakdown field increased by about 20% for an approximately twofold increase of the radius of curvature. These results indicate that the breakdown field is highly dependent on the boundary conditions, suggesting the need for reporting breakdown data always in close association with the measurement conditions. These findings might help future investigations in elucidating the ultimate breakdown mechanism/s of soft Elastomers
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Granularly coupled dielectric Elastomer actuators
2011Co-Authors: Federico Carpi, Massimo Nanni, Gabriele Frediani, Danilo De RossiAbstract:Dielectric Elastomer actuators (DEAs) have been demonstrated to represent today a high-performance technology for electroactive polymer mechatronics. As a means to improve versatility and safety of DEAs, so-called “hydrostatically coupled” DEAs (HC-DEAs) have recently been shown to offer new opportunities. HC-DEAs are based on an incompressible fluid that mechanically couples a DE-based active part to a passive part interfaced to the load, so as to enable hydrostatic transmission. Drawing inspiration from this concept, this paper presents a new kind of actuators, analogous to HC-DEAs, except for the fact that the fluid is replaced by fine powder. The related technology, here referred to as “granularly coupled” DEAs (GC-DEAs), relies entirely on solid-state materials. This permits to avoid drawbacks (such as handling and leakage) inherent to usage of fluids, especially those in liquid phase. This paper presents functionality and actuation performance of bubble-like GC-DEAs, in direct comparison with HC-DEAs. For this purpose, prototype actuators made of two prestretched membranes (2-cm wide and less than 2-mm high) of Acrylic Elastomer, coupled via talcum powder (for GC-DEA) or silicone grease (for HC-DEA), were manufactured and comparatively tested. As compared to HC-DEAs, GC-DEAs showed a higher maximum stress (2.1 kPa), the same maximum relative displacement (-100%), the same -3 dB bandwidth (3 Hz), and a higher resonance frequency (200 Hz). Advantages and drawbacks of GC-DEAs, in comparison with HC-DEAs, are preliminarily identified and discussed.
D K Tripathy - One of the best experts on this subject based on the ideXlab platform.
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multiwalled carbon nanotube filled ethylene Acrylic Elastomer nanocomposites influence of ionic liquids on the mechanical dynamic mechanical and dielectric properties
Polymer Composites, 2016Co-Authors: Bibhu Prasad Sahoo, Kinsuk Naskar, D K TripathyAbstract:Electrically conductive nanocomposites based on ethylene Acrylic Elastomer (AEM) and multiwalled carbon nanotube (MWNT) have been successfully prepared. Before mixing the MWNT is dispersed in ethanol in presence of ionic liquids such as 1-methyl-3-octylimidazolium chloride (MOIC) and 1-allyl-3-methyl imidazolium chloride (AMIC). Uniform dispersion of MWNT in the nanocomposites is achieved in presence of ionic liquid, which is confirmed by the high-resolution transmission electron microscopic (HRTEM) microphotographs. The tensile strength increases up to 6 phr of MWNT loading and above that it decreases. However, the tensile strength increases due to the incorporation of ionic liquid assisted dispersed MWNT. It is observed from the dynamic mechanical analysis (DMA) that the storage modulus (E′) and glass transition temperature (Tg) of AEM matrix increase by incorporation of MWNT. The E′ also increases and the tan δmax marginally decreases due to the incorporation of dispersed MWNT in presence of ionic liquids. The dielectric relaxation characteristic properties of AEM/MWNT nanocomposites such as dielectric permittivity (e′), AC conductivity (σac), impedance (Z*) have been studied as a function of frequency (101−106 Hz) in presence of ionic liquids. The e′ and σac increase with increasing the MWNT loading due to the easy orientation of dipoles and formation of interconnected conductive networks in the nanocomposites. The electromagnetic interference shielding effectiveness (EMISE) is studied in the X-band frequency range of 8 to 12 GHz, which significantly improved with increase in MWNT loading. POLYM. COMPOS., 2015. © 2015 Society of Plastics Engineers
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study of dielectric relaxation behavior of electron beam cured conductive carbon black filled ethylene Acrylic Elastomer
Journal of Materials Science, 2013Co-Authors: Bibhu Prasad Sahoo, Kinsuk Naskar, Abhinav K Dubey, R N P Choudhary, D K TripathyAbstract:Composites based on ethylene Acrylic Elastomer (AEM) filled with a special type of conductive carbon black (CCB) have been prepared by two-roll mixing mill. The compression-molded sheet of the prepared composites have been subjected to electron beam (EB) radiation dose up to 400 kGy to induce radiation crosslinked composites. The crosslinked density has been calculated according to Flory–Rehner equation and is found to increase with increasing EB dose and CCB loading. Chain scission-to-crosslink density has been calculated by Charlesby–Pinner equation, which shows decreasing trend with increasing radiation dose. The dielectric relaxation behaviors of different doses of EB-treated AEM/CCB composites have been extensively studied as a function of frequency of applied electric field (101–106 Hz), CCB loading [0–30 phr (parts per hundred)], temperature (25–120 °C), and EB dose (50–400 kGy). It is observed that the dielectric permittivity (e′) increases with CCB loading and temperature, but decreases with increasing EB dose. This can be explained on the basis of interfacial polarization. Based on dielectric loss tangent (tan δ) values, it is observed that the dielectric relaxation time decreases with increases in the filler loading and temperature. However, it increases with increase in the radiation doses. Both the real and imaginary parts of the impedance (Z′ and Z″) have been found to decrease with increase in conductive filler loading. The AC conductivity (σac) increases with increase in the CCB concentration, test temperature, and radiation doses, which is attributed to the more pronounced hopping and tunneling mechanism. The percolation threshold (φcrit) occurred in the range of 16 phr CCB loading. The dispersions of CCB phase in AEM matrix below and above percolation have been captured by the transmission electron microscope photomicrographs.
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conductive carbon black filled ethylene Acrylic Elastomer vulcanizates physico mechanical thermal and electrical properties
Journal of Materials Science, 2012Co-Authors: Bibhu Prasad Sahoo, Kinsuk Naskar, D K TripathyAbstract:The effect of conductive carbon black (CCB) on the physico-mechanical, thermal, and electrical properties have been investigated by various characterization techniques. Physico-mechanical properties of the vulcanizates were studied with variation of filler loading, which revealed that the tensile strength increased up to 20 phr (parts per hundred rubber) CCB loading, whereas at higher filler loading it decreased marginally. Furthermore, tensile modulus, tear strength, and hardness gradually increased with increase in filler loading. The compression set and abrasion loss decreased with increasing CCB loading. The bound rubber content (Bdr) of unvulcanized rubber was found to increase significantly with increasing CCB content. The crosslink density increased, whereas the swelling decreased with CCB loading. The thermal stability of the vulcanizates evaluated by thermogravimetric analysis (TGA) showed a minor increment with increase in CCB content. It is observed from the dynamic mechanical thermal analysis (DMTA) that the storage modulus (E′), loss modulus (E″), and glass transition temperature (T g) of ethylene Acrylic Elastomer (AEM) matrix increased by incorporation of CCB. The dielectric relaxation characteristics of AEM vulcanizates such as dielectric permittivity (e′), electrical conductivity (σ ac), and electric moduli (M′ and M″) have been studied as a function of frequency (101 to 106 Hz) at different filler loading. The variation of e′ with frequency and filler loading was explained based on the interfacial polarization of the fillers within a heterogeneous system. The e′ increased with increasing the CCB loading and it decreased with applied frequency. The frequency dependency of σ ac was investigated using conduction path theory and percolation threshold limit. The σ ac increased with increase in both CCB concentration and applied frequency. The M′ increased with applied frequency, however, it decreased above 30 phr filler. The M″ peak shifted towards higher frequency region and above 20 phr filler loading the peaks were not observed within the tested frequency region. The electromagnetic interference shielding effectiveness (EMISE) was studied in the X-band frequency region (8–12 GHz), which significantly improved with increase in CCB loading.
Michael Wissler - One of the best experts on this subject based on the ideXlab platform.
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A comparison between silicone and Acrylic Elastomers as dielectric materials in electroactive polymer actuators
Polymer International, 2010Co-Authors: Silvain Michel, Xuequn Q. Zhang, Michael Wissler, Christiane LöweAbstract:Soft Elastomers, mostly silicones and Acrylics, are interesting candidates as dielectric materials in electroactive polymer actuator technology. Generally, characteristics like large strain, high stress, high energy density, good efficiency and high response speed are required for actuator applications. However, some of these material properties may be contradictory. For this reason a comparison between Dow Corning silicone and 3M Acrylic Elastomers was made based on a set of six electromechanical tests for actuator applications. The silicone Elastomer shows a fast electromechanical response (3 s) with good reproducibility and the dissipated work is negligible and not frequency dependent. It also shows a stable mechanical behaviour over a wide temperature range. In contrast, the Acrylic Elastomer shows a slow electromechanical response with poor reproducibility. The dissipated work of the Acrylic Elastomer is significant: a strong frequency and temperature dependency of the dissipated work is observed for this material. The Dow Corning silicone (DC 3481) is a better material for many applications, where activation strains of less than 10% are sufficient. However, in applications where higher strains are required, it might be obligatory to use Acrylic Elastomers, because only these have the potential for use with activation strains beyond 10%. The electrical activation of a circular specimen is most useful in order to evaluate a material as a dielectric in electroactive polymer actuators. Copyright © 2009 Society of Chemical Industry
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electromechanical coupling in dielectric Elastomer actuators
Sensors and Actuators A-physical, 2007Co-Authors: Michael Wissler, Edoardo MazzaAbstract:Abstract In this paper the electromechanical coupling in dielectric Elastomer actuators is investigated. An equation proposed by Pelrine et al. [R.E. Pelrine, R.D. Kornbluh, J.P. Joseph, Electrostriction of polymer dielectrics with compliant electrodes as a means of actuation, Sens. Actuators A 64 (1998) 77–85] is commonly used for the calculation of the electrostatic forces in dielectric Elastomer systems. This equation is analyzed here with (i) energy consideration and (ii) numerical calculations of charge and force distribution. A new physical interpretation of the electrostatic forces acting on the dielectric Elastomer film is proposed, with contributions from in-plane and out-of-plane stresses. Representation of this force distribution using Pelrine's equation is valid for an incompressible material, such as the Acrylic Elastomer VHB 4910. Experiments are performed for the measurement of the dielectric constant ɛ r of the Acrylic Elastomer VHB 4910 for different film deformations. The values of ɛ r are shown to decrease with increasing pre-stretch ratio λ p , from 4.7 for the un-stretched film, down to 2.6 for equi-biaxial deformation with λ p = 5. This result is important in that it corrects the constant value of 4.7 largely applied in literature for pre-stretched dielectric Elastomer actuator modeling. With the results of this work the predictive capabilities of a model describing the three-dimensional passive and active actuator behavior are remarkably improved.
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mechanical behavior of an Acrylic Elastomer used in dielectric Elastomer actuators
Sensors and Actuators A-physical, 2007Co-Authors: Michael Wissler, Edoardo MazzaAbstract:Abstract The paper reports on extensive experimental work for the characterization of a dielectric Elastomer used as base material for electroactive polymer (EAP) actuators. The mechanical behavior of the Acrylic Elastomer VHB 4910 is characterized using large strain experiments (uniaxial and equibiaxial deformation) under force and displacement controlled loading conditions. Next to tensile and relaxation tests, experiments were conducted also using the so-called circular actuators. Over 40 actuators were produced (with different in-plane pre-strain levels) and activated with voltages between 2000 and 3500 V. The experimental data are useful for determining constitutive model parameters as well as for validating models and simulation procedures for electromechanical coupling in EAP actuators. A novel approach is proposed for finite element analysis of dielectric Elastomer actuator, which has been used in the present work for the evaluation of the experimental observations from circular actuators. Material parameters of different visco-hyperelastic models have been determined from a subset of the experimental data and the predictive capabilities of the models evaluated through comparisons with the remaining data. The prediction of the circular actuator behavior was satisfactory so that the proposed models might be useful for actuator design and optimization purposes. Limitations of the proposed constitutive model formulation are presented.
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effects of crosslinking prestrain and dielectric filler on the electromechanical response of a new silicone and comparison with Acrylic Elastomer
Smart Structures and Materials 2004: Electroactive Polymer Actuators and Devices (EAPAD), 2004Co-Authors: Xuequn Zhang, Michael Wissler, B Jaehne, Rolf Breonnimann, Gabor KovacsAbstract:Silicone and Acrylic Elastomers have received increased attention as dielectric electroactive polymer (EAP) materials for actuator technology. The goal of this work was to develop and characterize a new class of silicones (DC3481) and to compare it with Acrylic Elastomers. The influence of various types of hardeners, hardener concentration, prestrain and high dielectric organic fillers was studied by mechanical, electrical and electromechanical experiments. Furthermore the temperature dependence and the viscoelastic properties were investigated. The results show that by changing type and concentration of hardener, the Young's modulus can be varied. In order to increase the dielectric constant, the silicone was blended with organic materials. Compared to Acrylic Elastomers, this new class of silicone Elastomers has the advantage of a constant stiffness over a wide range of temperature and a lower viscosity that results in a higher response speed of the actuator.
Edoardo Mazza - One of the best experts on this subject based on the ideXlab platform.
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electromechanical coupling in dielectric Elastomer actuators
Sensors and Actuators A-physical, 2007Co-Authors: Michael Wissler, Edoardo MazzaAbstract:Abstract In this paper the electromechanical coupling in dielectric Elastomer actuators is investigated. An equation proposed by Pelrine et al. [R.E. Pelrine, R.D. Kornbluh, J.P. Joseph, Electrostriction of polymer dielectrics with compliant electrodes as a means of actuation, Sens. Actuators A 64 (1998) 77–85] is commonly used for the calculation of the electrostatic forces in dielectric Elastomer systems. This equation is analyzed here with (i) energy consideration and (ii) numerical calculations of charge and force distribution. A new physical interpretation of the electrostatic forces acting on the dielectric Elastomer film is proposed, with contributions from in-plane and out-of-plane stresses. Representation of this force distribution using Pelrine's equation is valid for an incompressible material, such as the Acrylic Elastomer VHB 4910. Experiments are performed for the measurement of the dielectric constant ɛ r of the Acrylic Elastomer VHB 4910 for different film deformations. The values of ɛ r are shown to decrease with increasing pre-stretch ratio λ p , from 4.7 for the un-stretched film, down to 2.6 for equi-biaxial deformation with λ p = 5. This result is important in that it corrects the constant value of 4.7 largely applied in literature for pre-stretched dielectric Elastomer actuator modeling. With the results of this work the predictive capabilities of a model describing the three-dimensional passive and active actuator behavior are remarkably improved.
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mechanical behavior of an Acrylic Elastomer used in dielectric Elastomer actuators
Sensors and Actuators A-physical, 2007Co-Authors: Michael Wissler, Edoardo MazzaAbstract:Abstract The paper reports on extensive experimental work for the characterization of a dielectric Elastomer used as base material for electroactive polymer (EAP) actuators. The mechanical behavior of the Acrylic Elastomer VHB 4910 is characterized using large strain experiments (uniaxial and equibiaxial deformation) under force and displacement controlled loading conditions. Next to tensile and relaxation tests, experiments were conducted also using the so-called circular actuators. Over 40 actuators were produced (with different in-plane pre-strain levels) and activated with voltages between 2000 and 3500 V. The experimental data are useful for determining constitutive model parameters as well as for validating models and simulation procedures for electromechanical coupling in EAP actuators. A novel approach is proposed for finite element analysis of dielectric Elastomer actuator, which has been used in the present work for the evaluation of the experimental observations from circular actuators. Material parameters of different visco-hyperelastic models have been determined from a subset of the experimental data and the predictive capabilities of the models evaluated through comparisons with the remaining data. The prediction of the circular actuator behavior was satisfactory so that the proposed models might be useful for actuator design and optimization purposes. Limitations of the proposed constitutive model formulation are presented.
Bibhu Prasad Sahoo - One of the best experts on this subject based on the ideXlab platform.
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multiwalled carbon nanotube filled ethylene Acrylic Elastomer nanocomposites influence of ionic liquids on the mechanical dynamic mechanical and dielectric properties
Polymer Composites, 2016Co-Authors: Bibhu Prasad Sahoo, Kinsuk Naskar, D K TripathyAbstract:Electrically conductive nanocomposites based on ethylene Acrylic Elastomer (AEM) and multiwalled carbon nanotube (MWNT) have been successfully prepared. Before mixing the MWNT is dispersed in ethanol in presence of ionic liquids such as 1-methyl-3-octylimidazolium chloride (MOIC) and 1-allyl-3-methyl imidazolium chloride (AMIC). Uniform dispersion of MWNT in the nanocomposites is achieved in presence of ionic liquid, which is confirmed by the high-resolution transmission electron microscopic (HRTEM) microphotographs. The tensile strength increases up to 6 phr of MWNT loading and above that it decreases. However, the tensile strength increases due to the incorporation of ionic liquid assisted dispersed MWNT. It is observed from the dynamic mechanical analysis (DMA) that the storage modulus (E′) and glass transition temperature (Tg) of AEM matrix increase by incorporation of MWNT. The E′ also increases and the tan δmax marginally decreases due to the incorporation of dispersed MWNT in presence of ionic liquids. The dielectric relaxation characteristic properties of AEM/MWNT nanocomposites such as dielectric permittivity (e′), AC conductivity (σac), impedance (Z*) have been studied as a function of frequency (101−106 Hz) in presence of ionic liquids. The e′ and σac increase with increasing the MWNT loading due to the easy orientation of dipoles and formation of interconnected conductive networks in the nanocomposites. The electromagnetic interference shielding effectiveness (EMISE) is studied in the X-band frequency range of 8 to 12 GHz, which significantly improved with increase in MWNT loading. POLYM. COMPOS., 2015. © 2015 Society of Plastics Engineers
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study of dielectric relaxation behavior of electron beam cured conductive carbon black filled ethylene Acrylic Elastomer
Journal of Materials Science, 2013Co-Authors: Bibhu Prasad Sahoo, Kinsuk Naskar, Abhinav K Dubey, R N P Choudhary, D K TripathyAbstract:Composites based on ethylene Acrylic Elastomer (AEM) filled with a special type of conductive carbon black (CCB) have been prepared by two-roll mixing mill. The compression-molded sheet of the prepared composites have been subjected to electron beam (EB) radiation dose up to 400 kGy to induce radiation crosslinked composites. The crosslinked density has been calculated according to Flory–Rehner equation and is found to increase with increasing EB dose and CCB loading. Chain scission-to-crosslink density has been calculated by Charlesby–Pinner equation, which shows decreasing trend with increasing radiation dose. The dielectric relaxation behaviors of different doses of EB-treated AEM/CCB composites have been extensively studied as a function of frequency of applied electric field (101–106 Hz), CCB loading [0–30 phr (parts per hundred)], temperature (25–120 °C), and EB dose (50–400 kGy). It is observed that the dielectric permittivity (e′) increases with CCB loading and temperature, but decreases with increasing EB dose. This can be explained on the basis of interfacial polarization. Based on dielectric loss tangent (tan δ) values, it is observed that the dielectric relaxation time decreases with increases in the filler loading and temperature. However, it increases with increase in the radiation doses. Both the real and imaginary parts of the impedance (Z′ and Z″) have been found to decrease with increase in conductive filler loading. The AC conductivity (σac) increases with increase in the CCB concentration, test temperature, and radiation doses, which is attributed to the more pronounced hopping and tunneling mechanism. The percolation threshold (φcrit) occurred in the range of 16 phr CCB loading. The dispersions of CCB phase in AEM matrix below and above percolation have been captured by the transmission electron microscope photomicrographs.
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conductive carbon black filled ethylene Acrylic Elastomer vulcanizates physico mechanical thermal and electrical properties
Journal of Materials Science, 2012Co-Authors: Bibhu Prasad Sahoo, Kinsuk Naskar, D K TripathyAbstract:The effect of conductive carbon black (CCB) on the physico-mechanical, thermal, and electrical properties have been investigated by various characterization techniques. Physico-mechanical properties of the vulcanizates were studied with variation of filler loading, which revealed that the tensile strength increased up to 20 phr (parts per hundred rubber) CCB loading, whereas at higher filler loading it decreased marginally. Furthermore, tensile modulus, tear strength, and hardness gradually increased with increase in filler loading. The compression set and abrasion loss decreased with increasing CCB loading. The bound rubber content (Bdr) of unvulcanized rubber was found to increase significantly with increasing CCB content. The crosslink density increased, whereas the swelling decreased with CCB loading. The thermal stability of the vulcanizates evaluated by thermogravimetric analysis (TGA) showed a minor increment with increase in CCB content. It is observed from the dynamic mechanical thermal analysis (DMTA) that the storage modulus (E′), loss modulus (E″), and glass transition temperature (T g) of ethylene Acrylic Elastomer (AEM) matrix increased by incorporation of CCB. The dielectric relaxation characteristics of AEM vulcanizates such as dielectric permittivity (e′), electrical conductivity (σ ac), and electric moduli (M′ and M″) have been studied as a function of frequency (101 to 106 Hz) at different filler loading. The variation of e′ with frequency and filler loading was explained based on the interfacial polarization of the fillers within a heterogeneous system. The e′ increased with increasing the CCB loading and it decreased with applied frequency. The frequency dependency of σ ac was investigated using conduction path theory and percolation threshold limit. The σ ac increased with increase in both CCB concentration and applied frequency. The M′ increased with applied frequency, however, it decreased above 30 phr filler. The M″ peak shifted towards higher frequency region and above 20 phr filler loading the peaks were not observed within the tested frequency region. The electromagnetic interference shielding effectiveness (EMISE) was studied in the X-band frequency region (8–12 GHz), which significantly improved with increase in CCB loading.
