Morphology,thermal, and electrical properties of polypropylene hybrid composites co‐filled with multi‐walled carbon nanotubes and graphene nanoplatelets

In this study, nanocomposites of polypropylene (PP) with various loadings of multi‐wall carbon nanotubes (MWCNT) and graphene nanoplatelets (GnP) were formed by masterbatch dilution/mixing approach from individual masterbatches PP‐MWCNT and PP‐GnP. Melt mixing on a twin‐screw extruder at two different processing temperatures was followed by characterization of morphology by transmitted‐light microscopy including the statistical analysis of agglomeration behavior. The influence of processing temperature and weight fractions of both nanofillers on the dispersion quality is reported. Thermal properties of the nanocomposites investigated by DSC and TGA show sensitivity to the nanofillers weight fraction ratio and to processing conditions. Electrical conductivity is observed to increase up to an order of magnitude with the concentration of each nanofiller increasing from 0.5 wt % to 1.0 wt %. This is related with a decrease of electrical conductivity observed for unequal concentration of both nanofillers. This particular behavior shows the increase of electrical properties for higher MWCNT loadings and the increase of thermo‐mechanical properties for higher GnP loadings. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42793.     

Improving thermal conductivity and shear strength of carbon nanotubes/epoxy composites via thiol‐ene click reaction

This study investigates the effect of the thiol‐ene click reaction on thermal conductivity and shear strength of the epoxy composites reinforced by various silane‐functionalized hybrids of sulfhydryl‐grafted multi‐walled carbon nanotubes (SH‐MWCNTs) and vinyl‐grafted MWCNTs (CC‐MWCNTs). The results of Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, thermal gravimetric analysis (TGA), and transmission electron microscopy (TEM) show that the sulfhydryl groups and vinyl groups are successfully grafted onto the surface of MWCNTs, after treatment of MWCNT with triethoxyvinylsilane and 3‐mercaptopropyltrimethoxysilane, respectively. Scanning electron microscopy (SEM), HotDisk thermal constant analyzer (HotDisk), optical microscope, and differential scanning calorimetry (DSC) are used to characterize the resultant composites. It is demonstrated that the hybrid of 75 wt % SH‐MWCNTs and 25 wt % CC‐MWCNTs has better dispersion and stability in epoxy matrix, and shows a stronger synergistic effect in improving the thermal conductivity of epoxy composite via the thiol‐ene click reaction with 2,2′‐azobis(2‐methylpropionitrile) as thermal initiator. Furthermore, the tensile shear strength results of MWCNT/epoxy composites and the optical microscopy photographs of shear failure section indicate that the composite with the hybrid MWCNTs has higher shear strength than that with raw MWCNTs. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44579.     

Electrically conductive polycarbonate/ethylene‐propylene copolymer/multi‐walled carbon nanotubes nanocomposites with improved mechanical properties

In this article, the effect of Multi‐walled carbon nanotubes (MWCNTs) on the electrical conductivity and mechanical properties of polycarbonate (PC) toughened with cross‐linked ethylene‐propylene copolymer (EPC) was investigated. The solubility parameters of the PC and EPC were calculated using Hoy methods to clarify the miscibility of the polymer blends. It could be concluded that in the cooled state, the blends form a heterogeneous structure with two separate phases. The tensile, flexural, impact toughness properties of the PC/EPC blend and PC/EPC/MWCNT nanocomposites were carried out to illuminate the optimum concentration of polymer blends and MWCNTs. The 335% increment for the impact strength results appeared with combination of 10% EPC in the PC matrix. The flexural modulus and strength of PC/EPC blend increased by 75.1% and 59.1%, respectively. The Nielsen model was performed to fit the best curve of theoretical simulation to experimental results for elastomeric dispersed in the plastic matrix. Halpin‐Tsai model was applied to estimate the stiffness of nanocomposites blends with different volume fraction and aspect ratio of MWCNTs in the PC/EPC blends. Finally, in the presence of MWCNTs, all nanocomposite samples were semi‐conducting and the percolation threshold of the PC/EPC (10%) blends was between 0.5% and 1.0% MWCNTs. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44661.     

Thermal conductivity and dielectric properties of polypropylene‐based hybrid compounds containing multiwalled carbon nanotubes

In this article, we explore the possibility to develop composites with improved thermal conductivity and electrically insulating properties. The strategy adopted is to combine a thermal and electrical conductive filler (multiwalled carbon nanotubes) with secondary dielectric (but thermally conductive) fillers. To this end, particles with different compositions, sizes, and shape were used as secondary fillers and the composites, prepared by melt compounding, are characterized in terms of thermal and dielectric properties. Results show that, in ternary formulations, an increase of thermal conductivity is always verified for all kind of secondary particles. Analogously, increments in electrical conductivity are observed for ternary compounds containing larger size secondary fillers, while a significant reduction is achieved with the addition of smaller ones. This behavior is explained in terms of mutual distribution of the fillers and is consistent with direct (scanning electron microscopy) and indirect (rheological) observations. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46470.     

Mechanical and thermal transmission properties of carbon nanofiber‐dispersed carbon/phenolic multiscale composites

The present article reports the development and characterization of carbon nanofiber (CNF)‐incorporated carbon/phenolic multiscale composites. Vapor‐grown CNFs were dispersed homogeneously in to phenolic resin using an effective dispersion route, and carbon fabrics were subsequently impregnated with the CNF‐dispersed resin to develop carbon fiber/CNF/phenolic resin multiscale composites. Mechanical and thermal transmission properties of multiscale composites were characterized. Elastic modulus and thermal conductivity of neat carbon/phenolic and multiscale composites were predicted and compared with the experimental results. It was observed that incorporation of only 1.5 wt % CNF resulted in 10% improvement in Young's modulus, 12% increase in tensile strength, and 36% increase in thermal conductivity of carbon/phenolic composites. Fracture surface of composite samples revealed the formation of stronger fiber/matrix interface in case of multiscale composites than neat carbon/phenolic composites. Enhancement of above properties through CNF addition has been explained, and the difference between the predicted values and experimental results has been discussed. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Preparation and properties of styrene‐butadiene rubber nanocomposites blended with carbon black‐graphene hybrid filler

Graphene has become an attractive reinforcing filler for rubber materials, but its dispersion in rubber is still a big challenge. In this work, a novel carbon black‐reduced graphene (CB‐RG) hybrid filler was fabricated and blended with styrene‐butadiene rubber (SBR) via simple two‐roll mill mixing. The prepared CB‐RG hybrids had a microstructure with small CB agglomerates adsorbed onto graphene surfaces. CB acted as a barrier preventing the RG sheets from restacking even after drying. Homogeneous dispersion of graphene sheets in SBR matrix was observed by the mechanical mixing method based on the application of the CB‐RG hybrid fillers. Dynamic mechanical analysis showed that Tg of the SBR/CB‐RG blend was higher than that of the SBR/CB blend indicating strong interfacial interactions between RG and SBR due to the high surface area of graphene and the π‐π interaction between SBR and graphene. The tensile properties of SBR/CB‐RG composites improved significantly and the volume resistivity decreased compared with the SBR/CB blends. The thermal stability of SBR composites filled with CB and CB‐RG showed slight difference. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41309.     

Structure,mechanical, and electrical properties of high‐density polyethylene/multi‐walled carbon nanotube composites processed by compression molding and blown film extrusion

The structure and properties of melt mixed high‐density polyethylene/multi‐walled carbon nanotube (HDPE/MWCNT) composites processed by compression molding and blown film extrusion were investigated to assess the influence of processing route on properties. The addition of MWCNTs leads to a more elastic response during deformations that result in a more uniform thickness distribution in the blown films. Blown film composites exhibit better mechanical properties due to the enhanced orientation and disentanglement of MWCNTs. At a blow up ratio (BUR) of 3 the breaking strength and elongation in the machine direction of the film with 4 wt % MWCNTs are 239% and 1054% higher than those of compression molded (CM) samples. Resistivity of the composite films increases significantly with increasing BURs due to the destruction of conductive pathways. These pathways can be recovered partially using an appropriate annealing process. At 8 wt % MWCNTs, there is a sufficient density of nanotubes to maintain a robust network even at high BURs. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42665.     

Graphene nanosheets‐filled epoxy composites prepared by a fast dispersion method

Graphene nanosheets‐filled epoxy composites (GNS/Epoxy) were prepared at different filler loading levels from 0.25 to 3.00 wt %. A fast dispersion method as short as 5 min is employed to disperse GNS in epoxy matrix, which was enough for the homogeneous dispersion of GNS with the help of high ultrasonic frequency of 100 kHz and power of 200 W and high heat treatment temperature of 70 °C. The maximum electrical conductivity and thermal conductivity of the composites achieved 0.058 S m^?1 and 0.57 W m^?1 K^?1, respectively, with a low electrical percolation threshold of 1.50 wt %. The electrical conductivities were further predicted by percolation theory and found to agree well with the experimental results, which indicated that the graphene nanosheets dispersed very well in the matrix even at very short processing time. The results showed that the microstructures, thermal, electrical, and mechanical properties of epoxy polymer were significantly improved by adding a low amount of graphene nanosheets. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45152.     

HDPE composites strengthened–toughened synergistically by l‐aspartic acid functionalized graphene/carbon nanotubes hybrid nanomaterials

Ethylenediamine (EDA) covalently functionalized graphene sheets (GS‐EDA) and acidized carbon nanotubes (MWNTs‐COOH) were first prepared, followed by synthesizing l ‐aspartic acid functionalized GS‐EDA/MWNTs‐COOH (LGC) hybrid nanomaterials by using l ‐aspartic acid as a bridging agent. Then nanocomposites of high density polyethylene‐g ‐maleic anhydride (HDPE‐g ‐MAH) synergistic strengthening–toughening using LGC hybrids were prepared via melt compounding method. The surface structure of filler was characterized by using infrared (FTIR) and Raman spectrum. The synergistic strengthening–toughening effects of LGC hybrids on the HDPE‐g ‐MAH were investigated by scanning electron microscopy (SEM), dynamic mechanical analysis (DMA), thermal gravimetric analysis (TGA), tensile, and impact tests. FTIR showed that EDA has been grafted on the graphene sheets, and ? COOH group has been introduced into MWNTs. The l ‐aspartic acid connected GS‐EDA and MWNTs‐COOH through chemical bonds. SEM observations showed that LGC hybrids were homogeneously dispersed in HDPE‐g ‐MAH nanocomposites. Tensile and impact tests indicated that the mechanical properties of nanocomposites were improved obviously when LGC hybrid nanomaterials were incorporated simultaneously. DMA analysis indicated that the storage modulus of composites was higher than that of pure HDPE‐g ‐MAH matrix. TGA results revealed that the maximum decomposition temperature of HDPE‐g ‐MAH composites containing 0.75 wt % of LGC showed 11.5 °C higher than that of HDPE‐g ‐MAH matrix. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45055.     

Preparation and characterization of extruded nanocomposite based on polycarbonate/butadiene‐acrylonitrile‐styrene blend filled with multiwalled carbon nanotubes

Nanocomposites of polycarbonate/acrylonitrile‐butadiene‐styrene (PC/ABS) with multiwall carbon nanotubes (MWCNT) prepared by masterbatch dilution are investigated in this work. Melt compounding with twin screw extruder is followed by complete characterization of morphology, rheological‐, mechanical‐, and thermal‐properties of the nanocomposites. Light‐transmission‐ and scanning electron microscopy shows the preferential location of MWCNT in the PC. Nevertheless, relatively good dispersion in the whole matrix is achieved, what is corroborated with the specific mechanical energy. The study of viscoelastic properties of PC/ABS‐MWCNT shows the fluid–solid transition below 0.5 wt % MWCNT. Beyond this point the continuous nanofiller network is formed in the matrix promoting the reinforcement. Addition of 0.5 wt % MWCNT reduces ductility of PC/ABS and enhances Young's modulus by about 30% and yield stress by about 20%. Moreover, theoretical values of stiffness calculated within this work agree with the experimental data. Electrical conductivity, showing percolation at 2.0 wt % MWCNT, are influenced by processing temperature. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40271.     

Electrical conductivity and tensile properties of block‐copolymer‐wrapped single‐walled carbon nanotube/poly(methyl methacrylate) composites

Poly(methyl methacrylate) (PMMA) composites containing raw or purified single‐walled carbon nanotubes (SWCNTs) are prepared by in situ polymerization and solution processing. The SWCNTs are purified by centrifugation in a Pluronic surfactant, which consists of polyethyleneoxide and polypropyleneoxide blocks. Both the effects of SWCNT purity and non‐covalent functionalization with Pluronic are evaluated. Electrical conductivity of PMMA increases by 7 orders of magnitude upon the integration of raw or purified SWCNTs. The best electrical properties are measured for composites made of purified SWCNTs and prepared by in situ polymerization. Strains at fracture of the SWCNT/PMMA composites are nearly identical to those of the neat matrix. A certain decrease in the work to fracture is measured, particularly for composites containing purified SWCNTs (?31.6%). Fractography and Raman maps indicate that SWCNT dispersion in the PMMA matrix improves upon the direct addition of Pluronic, while dispersion becomes more difficult in the case of purified SWCNTs. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41547.     

High electrical conductivity of nylon 6 composites obtained with hybrid multiwalled carbon nanotube/carbon fiber fillers

The synergetic effect of multiwalled carbon nanotubes (MWNTs) and carbon fibers (CFs) in enhancing the electrical conductivity of nylon 6 (PA6) composites was investigated. To improve the compatibility between the fillers and the PA6 resin, we grafted γ‐aminopropyltriethoxy silane (KH‐550) onto the MWNTs and CFs after carboxyl groups were generated on their surface by chemical oxidation with nitric acid. Fourier transform infrared spectroscopy and thermogravimetric analysis proved that the KH‐550 molecules were successfully grafted onto the surface of the MWNTs and CFs. Scanning electron microscopy and optical microscopy showed that the obtained modified fillers reduced the aggregation of fillers and resulted in better dispersion and interfacial compatibility. We found that the electrical percolation threshold of the MWNT/PA6 and CF/PA6 composites occurred when the volume fraction of the fillers were 4 and 5%, respectively. The MWNT/CF hybrid‐filler system exhibited a remarkable synergetic effect on the electrically conductive networks. The MWNT/7% CF hybrid‐filler system appeared to show a second percolation when the MWNT volume fraction was above 4% and a volume resistivity reduction of two orders of magnitude compared with the MWNT/PA6 system. The mechanical properties of different types of PA6 composites with variation in the filler volume content were also studied. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40923.     

Mechanical and thermal properties of hierarchical composites enhanced by pristine graphene and graphene oxide nanoinclusions

Epoxy resin nanocomposites incorporated with 0.5, 1, 2, and 4 wt % pristine graphene and modified graphene oxide (GO) nanoflakes were produced and used to fabricate carbon fiber‐reinforced and glass fiber‐reinforced composite panels via vacuum‐assisted resin transfer molding process. Mechanical and thermal properties of the composite panels—called hierarchical graphene composites—were determined according to ASTM standards. It was observed that the studied properties were improved consistently by increasing the amount of nanoinclusions. Particularly, in the presence of 4 wt % GO in the resin, tensile modulus, compressive strength, and flexural modulus of carbon fiber (glass fiber) composites were improved 15% (21%), 34% (84%), and 40% (68%), respectively. Likewise, with inclusion of 4 wt % pristine graphene in the resin, tensile modulus, compressive strength, and flexural modulus of carbon fiber (glass fiber) composites were improved 11% (7%), 30% (77%), and 34% (58%), respectively. Also, thermal conductivity of the carbon fiber (glass fiber) composites with 4% GO inclusion was improved 52% (89%). Similarly, thermal conductivity of the carbon fiber (glass fiber) composites with 4% pristine graphene inclusion was improved 45% (80%). The reported results indicate that both pristine graphene and modified GO nanoflakes are excellent options to enhance the mechanical and thermal properties of fiber‐reinforced polymeric composites and to make them viable replacement materials for metallic parts in different industries, such as wind energy, aerospace, marine, and automotive. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40826.     

Electrical conductivity and mechanical performance of multiwalled CNT‐filled polyvinyl chloride composites subjected to tensile load

This article reports a study on the strain‐sensitive conductivity (tensoresistivity) and mechanical properties of polyvinyl chloride/multiwalled carbon nanotube (PVC/MWCNT) composites subjected to tensile loading at different strain rates for potential use in sensor‐enabled geosynthetics and other applications involving electrically conductive polymer composites. Results indicate that adding 0.5 wt % MWCNT to the composite results in 57% reduction in its ultimate (failure) strain and a fivefold increase in its tensile modulus while leaving its ultimate strength almost unchanged. Laser scanning confocal microscopy is used to investigate the microscopic failure mechanism of the composite and how it contributes to the strain‐sensitive conductivity of the composites. It is observed that tensile fractures are initiated from inside the largest bundles between 18% and 36% strain and continue through further fractal‐like fracturing in smaller bundles. Gauge factors (e.g., 3.17) comparable to or exceeding those of typical strain gauges are obtained for the composite, indicating its strong potential for structural performance monitoring and damage detection applications. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43665.     

Effects of substitution for carbon black with graphene oxide or graphene on the morphology and performance of natural rubber/carbon black composites

In this study, nanosheets including graphene oxide (GO) and reduced graphene oxide (rGO), were incorporated into natural rubber (NR), to study the effects of substituting GO or rGO for carbon black (CB) on the structure and performance of NR/CB composites. The morphological observations revealed the dispersion of CB was improved by partially substituting nanosheets for CB. The improvements in static and dynamic mechanical properties were achieved at small substitution content of GO or rGO nanosheets. With substitution of rGO nanosheets, significant improvement in flex cracking resistance was achieved. NR/CB/rGO (NRG) composites has a much lower heat build‐up value compared with NR/CB/GO (NG) composites at a high load of nanosheets. However, both GO and rGO tended to aggregate at a high concentration, which led to the poor efficiency on enhancing the dynamic properties, or even deteriorate the performance of rubber composites. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41832.     

Magnetically aligning multilayer graphene to enhance thermal conductivity of silicone rubber composites

The increasing demand for packaging materials calls for new technologies to achieve excellent thermal conductivity of polymer composites with low content of thermal conductive filler. This article prepared a kind of magnetically functionalized multilayer graphene (Fe₃O₄@MG) via electrostatic interactions, which efficiently enhanced the thermal conductivity of silicone rubber (SR) composites by the alignment of Fe₃O₄@MG in an external magnetic field. The morphology and structure of the Fe₃O₄@MG together with the thermal conductivity of corresponding Fe₃O₄@MG/SR composites were systematically investigated by SEM, TEM, XRD, elemental mapping, and thermal conductivity tester. The obtained results showed that Fe₃O₄@MG was induced to form chain-like bundles in silicone rubber matrix under the applied magnetic field, which enhanced the MG–MG interaction, and formed effective thermal pathways in the alignment direction. Furthermore, as coating mass ratio of Fe₃O₄@MG increased, the thermal conductivity of randomly oriented Fe₃O₄@MG/silicone rubber composites (R-Fe₃O₄@MG/SR) decreased gradually, whereas the through-plane thermal conductivity of vertically aligned Fe₃O₄@MG/silicone rubber composites (V-Fe₃O₄@MG/SR) increased even filled with same contents of thermal conductive filler. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47951.     

High performance polyurethane composites with isocyanate‐functionalized carbon nanotubes: Improvements in tear strength and scratch hardness

A microwave‐assisted functionalization of carbon nanotubes (CNTs) with isocyanate groups allowed a reduction of functionalization time from 24 h to 30 min with no change in the degree of functionalization or in the nanotube characteristics. Polymer nanocomposites with enhanced mechanical properties were obtained because of the tailored interface by the covalent linkage between the surface‐modified multiwalled‐carbon nanotubes (MWCNTs) and an elastomeric polyurethane (PUE) matrix. The mechanical data revealed that the composite containing 0.25 wt % of MWCNT‐NCO showed an increase of 31% in tear strength and 28% in static toughness. A good adhesion between the matrix and individually dispersed nanotubes was observed in the scanning electron microscopy and transmission electron microscopy images. Nanoindentation and nanoscratch experiments were conducted to investigate the properties on the sub‐surface. An increase by a factor of 3 in the scratch hardness was observed for the composite with 0.50 wt % of MWCNT‐NCO with respect to the neat PUE. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44394.     

Mechanical properties of carbon fiber reinforced bisphenol A dicyanate ester composites modified with multiwalled carbon nanotubes

A novel electrophoretic deposition (EPD) method was employed for grafting multiwalled carbon nanotubes (MWCNTs) on carbon fibers, which, after impregnation with bisphenol A dicyanate ester (BADCy), synergistically reinforced BADCy matrix composites (CNT‐C/BADCy). The effect of MWCNT presence on the mechanical properties of the composites was investigated. Composite tensile strength increased by 45.2% for an EPD duration of 2 min, while flexural strength exhibited a decreasing trend with EPD duration. Optical microscopy revealed that the existence of MWCNTs enhanced the fiber‐matrix interface while a large number of CNTs were observed to have pulled‐out from the matrix, a finding which explained the observed tensile strength increase in terms of energy dissipation by the specific toughening mechanism. The flexural strength decrease of the composites with CNTs as compared to specimens without nanotubes was found linked to the increased stress concentration in the BADCy matrix due to tube presence which weakens the adhesion between carbon fabrics. In a word, carbon nanotubes will enhance the micro interface and weaken the macro interface of the composites. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45100.     

Hot‐melt adhesives based on co‐polyamide and multiwalled carbon nanotubes

Composites of two hot melt adhesives based on co‐polyamides, one high viscosity (coPA_A), the other low viscosity (coPA_B), and multiwalled carbon nanotubes (MWCNTs) were prepared using twin‐screw extrusion via dilution of masterbatches. Examination of these composites across the length scales confirmed that the MWCNTs were uniformly dispersed and distributed in the polymer matrices, although some micron size agglomerations were also observed. A rheological percolation was determined from oscillatory rheology measurements at a mass fraction of MWCNTs below 0.01 for coPA_B and, between 0.01 and 0.02 for coPA_A. Significant increases in complex viscosity and storage modulus confirmed the “pseudo‐solid” like behavior of the composite materials. Electrical percolation, determined from dielectric spectroscopy was, found to be at 0.03 and 0.01 MWCNT mass fraction for coPA_A and coPA_B based composites, respectively. Addition of MWCNTs resulted in heterogeneous nucleation and altered the crystallization kinetics of both copolymers. Indirect evidence from contact angle measurements and surface energy calculations confirmed that MWCNT addition enhanced the adhesive properties of coPA_B to a level similar to coPA_A. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45999.     

Shielding effectiveness of carbon‐filled polycarbonate composites

In this project, varying amounts of three different carbons [carbon black (CB), carbon nanotubes (CNT), and graphene nanoplatelets (GNP)] were added to polycarbonate (PC). The resulting single filler composites were tested for shielding effectiveness (SE). The effects of single fillers and combinations of two different carbon fillers were studied via a factorial design. At the highest single filler loadings, the following SE results were obtained at 800 MHz: 18.9 dB for 10 wt % CB/PC, 18.4 dB for 8 wt % CNT/PC, and 6.3 dB for 15 wt % GNP/PC. The highest SE value of 21.4 dB was measured for the 5 wt % CB/5 wt % CNT/PC composite and could be used in SE applications (typically > 20 dB is needed). Statistically significant equations were developed that could be used to predict the SE of composites containing these fillers. In addition, it was determined that the composite SE is higher than what would be expected from the additive effect of each single filler for the CB/GNP/PC composites. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42719.