Preparation and thermal,electrical, and morphological properties of multiwalled carbon nanotubeand epoxy composites

Multiwalled carbon nanotube (MWCNT)/epoxy composites are prepared, and the characteristics and morphological properties are studied. Scanning electron microscopy microphotographs show that MWCNTs are dispersed on the nanoscale in the epoxy resin. The glass‐transition temperature (T_g) of MWCNT/epoxy composites is dramatically increased with the addition of 0.5 wt % MWCNT. The T_g increases from 167°C for neat epoxy to 189°C for 0.5 wt % CNT/epoxy. The surface resistivity and bulk resistivity are decreased when MWCNT is added to the epoxy resins. The surface resistivity of CNT/epoxy composites decreases from 4.92 × 10¹² Ω for neat epoxy to 3.03 × 10⁹ Ω for 1 wt % MWCNT/epoxy. The bulk resistivity decreases from 8.21 × 10¹⁶ Ω cm for neat epoxy to 6.72 × 10⁸ Ω cm for 1 wt % MWCNT/epoxy. The dielectric constant increases from 3.5 for neat epoxy to 5.5 for 1 wt % MWCNT/epoxy. However, the coefficient of thermal expansion is not affected when the MWCNT content is less than 0.5 wt %. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1272–1278, 2007     

Rheology,crystallization behaviors,and thermal stabilities of poly(butylene succinate)/pristine multiwalled carbon nanotube composites obtained by melt compounding

Poly(butylene succinate) (PBS)/pristine raw multiwalled carbon nanotube (MWCNT) composites were prepared in this work via simple melt compounding. Morphological observations indicated that the MWCNTs were well dispersed in the PBS matrix. Moreover, the incorporation of MWCNTs did not affect the crystal form of PBS as measured by wide‐angle X‐ray diffraction. The rheology, crystallization behaviors, and thermal stabilities of PBS/MWCNT composites were studied in detail. Compared with neat PBS, the incorporation of MWCNTs into the matrix led to higher complex viscosities (|η*|), storage modulus (G′), loss modulus (G″), shear thinning behaviors, and lower damping factor (tan δ) at low frequency range, and shifted the PBS/MWCNT composites from liquid‐like to solid‐like, which affected the crystallization behaviors and thermal stabilities of PBS. The presence of a very small quantity of MWCNTs had a significant heterogeneous‐nucleation effect on the crystallization of PBS, resulting in the enhancement of crystallization temperature, i.e., with the addition of 0.5 wt % MWCNTs, the values of T_c of PBS/MWCNT composites could attain to 90°C, about 6°C higher than that of neat PBS, whereas the values of T_c increased slightly with further increasing the MWCNTs content. The thermogravimetric analysis illustrated that the thermal stability of PBS was improved with the addition of MWCNTs compared with that of neat PBS. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Preparation of epoxy composites with CTAB‐modified BN and MWCNTs

In this study, multi‐walled carbon nanotubes (MWCNTs) and boron nitride (BN) were functionalized with cetyltrimethylammonium bromide (CTAB) at both pH 5.5 and pH 11. These MWCNT‐CTAB and BN‐CTAB particles used to prepare the composites were dispersed in a bisphenol A (DGEBA)‐type epoxy resin (ER) system at room temperature. The TGA analysis showed that the BN composite can significantly improve the thermal stability of neat ER at temperatures above 400 °C. The curing degrees of the nanocomposites were calculated to be approximately the same values as neat ER using the Beer–Lambert law from FTIR spectra. The best electrical conductivity of the composites obtained was 3.10 × 10⁻³ S/cm for ER/MWCNT‐CTAB (pH 5.5). The surface hardness, Young's modulus, and tensile strength of the composites were examined. The surface hardness values of the ER/MWCNT‐CTAB composites were higher than those of the other composites. The composite morphology was characterized using X‐ray diffraction (XRD) and scanning electron microscopy (SEM). POLYM. COMPOS., 37:3423–3432, 2016. © 2015 Society of Plastics Engineers     

Direct functionalization with 3,5‐substituted benzoic acids of multiwalled carbon nanotube/epoxy composites

Directly functionalized multiwalled carbon nanotubes (MWCNTs) with benzene‐1,3,5‐tricarboxylic acid (BTC) and 3,5‐diaminobenzoic acid (DAB) were successfully accomplished with less structural damage as confirmed by XPS and FT‐Raman results. Their dispersibility and thermal stability were achieved after the functionalization. The functional groups on MWCNT surfaces can accelerate the curing reaction of epoxy composites remarkable inducing rather low exothermic peak temperature (T_p) and exothermic heat of reaction (ΔH). The values of activation energy (E_a) obtained from Kissinger and Ozawa methods obviously decreased with the introduction of MWCNTs, especially DAB‐MWCNTs. The dynamic mechanical properties notably enhanced with the incorporation of unmodified and functionalized MWCNTs. The crosslink density (ρ) increased and free volume fraction (f_g) decreased, resulting in dramatic increase of glass transition temperatures (T_g) and decrease of coefficient of thermal expansion. Additionally, epoxy composites exhibited low dielectric constant close to that of neat epoxy resin. From these remarkable properties, MWCNT/epoxy composites can be considered as a good candidate for high performance insulation materials. POLYM. ENG. SCI., 53:2194–2204, 2013. © 2013 Society of Plastics Engineers     

Effect of amino‐functionalization of multi‐walled carbon nanotubes on the dispersion with epoxy resin matrix

Amino‐functionalization of multiwalled carbon nanotubes (MWCNTs) was carried out by grafting triethylenetetramine (TETA) on the surfaces of MWCNTs through the acid–thionyl chloride way. The amino‐functionalized MWCNTs show improved compatibility with epoxy resin and, as a result, more homogenous dispersion in the matrix. The mechanical, optical, and thermal properties of the amino‐functionalized MWCNT/epoxy composites were also investigated. It was found that introducing the amino‐functionalized MWCNTs into epoxy resin greatly increased the charpy impact strength, glass transition temperature, and initial decomposing temperature of cured epoxy resin. In addition, introducing unfunctionalized MWCNTs into epoxy resin was found greatly depressing the light transmission properties, which would affirmatively confine the application of the MWCNTs/epoxy composites in the future, while much higher light transmittance than that of unfunctionalized MWCNTs/epoxy composites was found for amino‐functionalized MWCNTs/epoxy composites. SEM of the impact cross section and TEM of ultrathin film of the amino‐functionalized MWCNTs/epoxy composites showed that the amino‐functionalized MWCNTs were wetted well by epoxy matrix. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 97–104, 2006     

Preparation,morphology, and properties of silane‐modified MWCNT/epoxy composites

Both epoxy resin and acid‐modified multiwall carbon nanotube (MWCNT) were treated with 3‐isocyanatopropyltriethoxysilane (IPTES). Scanning electron microscopy (SEM) and transmission electronic microscope (TEM) images of the MWCNT/epoxy composites have been investigated. Tensile strength of cured silane‐modified MWCNT (1.0 wt %)/epoxy composites increased 41% comparing to the neat epoxy. Young's modulus of cured silane‐modified MWCNT (0.8 wt %)/epoxy composites increased 52%. Flexural strength of cured silane‐modified MWCNT (1.0 wt %)/epoxy composites increased 145% comparing to neat epoxy. Flexural modulus of cured silane‐modified MWCNT (0.8 wt %)/epoxy composites increased 31%. Surface and volume electrical resistance of MWCNT/epoxy composites were decreased with IPTES‐MWCNT content by 2 orders and 6 orders of magnitude, respectively. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Mechanical properties of graphene nanoplatelet/epoxy composites

Because of their high‐specific stiffness, carbon‐filled epoxy composites can be used in structural components in fixed‐wing aircraft. Graphene nanoplatelets (GNPs) are short stacks of individual layers of graphite that are a newly developed, lower cost material that often increases the composite tensile modulus. In this work, researchers fabricated neat epoxy (EPON 862 with Curing Agent W) and 1–6 wt % GNP in epoxy composites. The cure cycle used for this aerospace epoxy resin was 2 h at 121°C followed by 2 h at 177°C. These materials were tested for tensile properties using typical macroscopic measurements. Nanoindentation was also used to determine modulus and creep compliance. These macroscopic results showed that the tensile modulus increased from 2.72 GPa for the neat epoxy to 3.36 GPa for 6 wt % (3.7 vol %) GNP in epoxy composite. The modulus results from nanoindentation followed this same trend. For loadings from 10 to 45 mN, the creep compliance for the neat epoxy and GNP/epoxy composites was similar. The GNP aspect ratio in the composite samples was confirmed to be similar to that of the as‐received material by using the percolation threshold measured from electrical resistivity measurements. Using this GNP aspect ratio, the two‐dimensional randomly oriented filler Halpin–Tsai model adjusted for platelet filler shape predicts the tensile modulus well for the GNP/epoxy composites. Per the authors' knowledge, mechanical properties and modeling for this GNP/epoxy system have never been reported in the open literature. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Preparation and properties of multi‐walled carbon nanotubes/carbon fiber/epoxy composites

Multi‐walled carbon nanotubes/carbon fiber (MWCNTs/CF) hybrid fillers are employed to prepare MWCNTs/CF/epoxy composites. Results reveal that a great improvement of the thermal conductivities of the epoxy composites with the addition of MWCNTs/CF hybrid fillers, and the thermal conductivity of the MWCNTs/CF/epoxy composites is 1.426 W/mK with 8 vol% treated MWCNTs/CF hybrid fillers (5 vol% MWCNTs + 3 vol% CF). Both the flexural and impact strength of the MWCNTs/CF/epoxy composites are increased firstly, but decreased with the excessive addition of MWCNTs. The flexural and impact strength of the MWCNTs/epoxy composites are optimal with 2 vol% MWCNTs. For a given MWCNTs/CF hybrid fillers loading, the surface treatment of MWCNTs/CF hybrid fillers can further increase the thermal conductivities and mechanical properties of the MWCNTs/CF/epoxy composites. POLYM. COMPOS., 35:2150–2153, 2014. © 2014 Society of Plastics Engineers     

Preparation and thermal properties of bio‐based gallic acid epoxy/carbon nanotubes composites by cationic ring‐opening reaction

In order to prepare the bio‐based polymeric materials, a gallic acid epoxy resin (GA‐ER) is synthesized by using biodegradable gallic acid, and the nanocomposites of GA‐ER/glycidyl methacrylate (GMA)/multiwalled carbon nanotubes (MWCNTs) were prepared by dual hybrid cationic ring‐opening reaction. Differential scanning calorimetry (DSC) results show that the curing reaction temperature of the nanocomposites is between 150 and 225°C. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) results suggest that MWCNTs are homodispersing in the GA‐ER/GMA matrix when the MWCNTs content is not more than 1.0 wt%. The glass transition temperature of the nanocomposite with 0.5 wt% MWCNTs is 9.3°C higher than that of pure resin system. The initial thermal degradation temperature and degradation activation energies E_a of the nanocomposite with 1.0 wt% MWCNTs is 10°C and 68.6 kJ/mol higher than that the pure resin system, respectively. POLYM. COMPOS., 37:3093–3102, 2016. © 2015 Society of Plastics Engineers     

Fabrication and characterization of NBR/MWCNT composites by latex technology

To develop a rubber composite with excellent electrical properties, a sort of synthetic rubber, acrylonitrile butadiene rubber (NBR) with CN dipoles as matrix, multi‐walled carbon nanotubes (MWCNTs) as filler, was synthesized. NBR composites reinforced with 0.5, 1.5, 3, 10, and 20 phr MWCNT contents were fabricated by latex technology. The electrical conductivity, dielectric characteristics, and electromagnetic interference (EMI) shielding effectiveness at room temperature of NBR/MWCNT composites were investigated. MWCNTs were found well dispersed into NBR matrix even for 20 phr content by FESEM observation. The electrical conductivity increased with an increment of MWCNT content. The dielectric constant was over 10⁴ at 10³ Hz frequency for 10 and 20 phr MWCNTs‐reinforced NBR composites. It was attributed to the increased electrons and interface polarization. The improved conductivity and dielectric permittivity resulted in an enhanced EMI shielding effectiveness. The EMI shielding effectiveness reached 26 dB at 16.7 GHz frequency for NBR/20 phr MWCNT composite with 1.0 mm thickness. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers     

A comparative study on the properties of the different amino‐functionalized multiwall carbon nanotubes reinforced epoxy resin composites

Multiwall carbon nanotubes (MWCNTs) were amino‐functionalized by 1,2‐ethylenediamine (EDA)' triethylenetetramine (TETA), and dodecylamine (DDA), and investigated by fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, and thermogravimetric analysis (TGA). The dispersion of the DDA functionalized MWCNT in DMF is better than that of the MWCNT functionalized by the EDA and the TETA. Carbon nanotubes reinforced epoxy resin composites were prepared, and the effect of the amino‐functionalization on the properties of the composites was investigated by differential scanning calorimetry (DSC), dynamical mechanical analysis (DMA), and TGA. The composites reinforced by the MWCNTs demonstrate improvement in various mechanical properties. The increase of T_g of the composites with the addition of amino‐functionalized MWCNT compared to the T_g of the composites with the addition of unfunctionalized MWCNT was due to the chemical combination and the physical entanglements between amino group from modified MWNTs and epoxy group from the epoxy resin. The interfacial bonding between the epoxy and the amino group of the EDA and the TETA‐modified MWCNT is more important than the well dispersion of DDA‐modified MWCNT in the composites for the improvement of the mechanical properties. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

The role of a biobased epoxy monomer in the preparation of diglycidyl ether of bisphenol A/MWCNT composites

A biobased epoxy monomer (GA‐II) derived from gallic acid for multiwalls carbon nanotubes’ (MWCNTs) dispersion improvement is reported in this article. The aromatic group in its molecular structure made it to be absorbed onto the surface of MWCNTs via π‐π interactions and the GA‐II anchored MWCNT could be homogeneously dispersed in DGEBA matrix via sonication. That was proved by Raman and UV spectroscopy as well as scanning electron microscope. After curing reaction, the epoxy/MWCNT composites demonstrated enhanced mechanical properties, excellent thermal conductivity, and high electrical conductivity. With the addition of only 0.5 wt% GA‐II modified MWCNT, the tensile strength, tensile modulus, flexural strength, and flexural modulus of the composites were improved by 28%, 40%, 22%, and 16%, respectively. The thermal and electrical conductivities were also improved from 0.15 to 0.25 W/m K (67% increased) and from 0.7 × 10⁻¹⁴ to 0.24 × 10⁻⁴ S cm⁻¹ (10 orders increased). POLYM. COMPOS., 38:1640–1645, 2017. © 2015 Society of Plastics Engineers     

Synthesis and characterization of chlorinated soy oil based epoxy resin/glass fiber composites

Composites with good toughness properties were prepared from chemically modified soy epoxy resin and glass fiber without additional petroleum based toughening agent. Chlorinated soy epoxy (CSE) resin was prepared from soybean oil. The CSE was characterised by spectral, and titration method. The prepared CSE was blended with commercial epoxy resin in different ratios and cured at 85°C for 3 h, and post cured at 225°C for 2 h using m‐phenylene diamine (MPDA) as curing agent. The cure temperatures of epoxy/CSE/MPDA with different compositions were found to be in the range of (151.2–187.5°C). The composite laminates were fabricated using epoxy /CSE/MPDA‐glass fiber at different compositions. The mechanical properties such as tensile strength (248–299 MPa), tensile modulus (2.4–3.4 GPa), flexural strength (346–379 MPa), flexural modulus (6.3–7.8 GPa) and impact strength (29.7–34.2) were determined. The impact strength increased with the increase in the CSE content. The interlaminor fracture toughness (G_IC) values also increased from 0.6953 KJ/m² for neat epoxy resin to 0.9514 KJ/m² for 15%CSE epoxy‐modified system. Thermogravimetric studies reveal that the thermal stability of the neat epoxy resin was decreased by incorporation of CSE. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers     

Preparation and characterization of epoxy resin modified with alkoxysilane‐ functionalized poly(urethane‐imide) by the sol–gel process

The sol–gel process has been frequently employed for preparation of high performance silica/polymer composites. In this paper, novel sol–gel precursor triethoxysilane‐terminated poly(urethane‐imide) (PUI‐Si), combining the advantages of polyurethane (PU) and polyimide, was synthesized and characterized. Then PUI‐Si was incorporated into the epoxy resin matrix to prepare a series of EP/PUI‐Si organic‐inorganic hybrids through an in situ sol–gel process and crosslinking reactions. The thermal stability of EP/PUI‐Si hybrids was evaluated by thermogravimetric analysis and the results show that the PUI‐Si could significantly improve the thermal properties of epoxy resin. The initial decomposition temperature of composites with 50 wt% PUI‐Si reached 347.1 °C, 157.3 °C higher than that of neat epoxy resin. Furthermore, the tensile strength and breaking elongation can also be clearly improved by adding a suitable amount of PUI‐Si. Similarly, the water contact angle increased to 97.4° with 70 wt% PUI‐Si, showing a hydrophobic surface. The morphology was investigated by transmission electron microscopy and the results reveal that the silica particles are smaller than 20 nm and have a strong interaction with the epoxy resin matrix, resulting in the above‐mentioned high performance properties. Copyright © 2011 Society of Chemical Industry     

Enhanced Thermal Conductivity of Epoxy Composites with MWCNTs/AlN Hybrid Filler

To further improve the thermal conductivity of epoxy resin, the multi-walled carbon nanotube/aluminum nitride (MWCNTs/AlN) hybrid filler was employed to prepare thermal conductivity MWCNTs/AlN/epoxy composite by casting process, and the silane coupling reagent of γ-glycidoxy propyl trimethoxy silane(KH-560) was also used to functionalize the surface of MWCNTs and/or AlN. Results revealed that, the thermal conductivity of epoxy resin was improved remarkably with the addition of MWCNTs/AlN hybrid filler, a higher thermal conductivity of 1.04 W/mK could be achieved with 29 wt% MWCNTs/AlN hybrid filler (4 wt% MWCNTs +25 wt% AlN), about 5 times higher than that of native epoxy resin. And the epoxy composite with 29 wt% MWCNTs/AlN hybrid filler possessed better thermal conductivity and mechanical properties than those of single 5 wt% MWCNTs or 40 wt% AlN. The thermal decomposition temperature of MWCNTs/AlN/epoxy composite was increased with the addition of MWCNTs/AlN hybrid filler. For given filler loading, surface treatment of MWCNTs and/or AlN by KH-560 exhibited a positive effect on the thermal conductivity of epoxy composite.     

Thermal stability and kinetics analysis of epoxy composites modified with reactive polyol diluent and multiwalled carbon nanotubes

The effect of polyether polyol and amino‐functionalized multiwalled carbon nanotubes (NH₂‐MWCNTs) on the thermal stability of three‐phase (epoxy/polyol/NH₂‐MWCNTs) epoxy composites was investigated. Thermal stability and degradation characteristics of polyol/MWCNTs modified epoxy composites was evaluated using thermogravimetric analysis. The kinetics of thermal degradation was assessed from data scanned at 5, 10, and 20°C/min. Activation energy for degradation of epoxy nanocomposites was calculated using different differential and integral methods, that is, Kissinger's, Flynn–Wall–Ozawa, Coats–Redfern, and Horowitz–Metzger methods. In addition, the integral procedure decomposition temperature was determined to evaluate the inherent thermal stability of the modified composite system. Rate of thermal degradation in MWCNT/Polyol samples was found to be reduced significantly while activation energy of degradation was increased compared to unmodified epoxy composite. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41558.     

Effect of compatibilizer on morphology,thermal, and rheological properties of polypropylene/functionalized multi‐walled carbon nanotubes composite

Multi‐walled carbon nanotubes (MWCNTs) filled polypropylene (PP) composites were prepared by a corotating intermeshing twin screw extruder. To improve the dispersion of MWCNTs, the surface of MWCNT was modified with 1,10‐diaminodecane, and maleic anhydride grafted polypropylene (MA‐g‐PP) was used as a compatibilizer. Micrographs of well dispersed functionalized MWCNTs (diamine‐MWCNT) were observed due to the reaction between MA‐g‐PP and diamine‐MWCNT in PP/MA‐g‐PP/diamine‐MWCNTs composites. The different behaviors in crystallization and melting temperatures of PP/MA‐g‐PP/diamine‐MWCNTs composite were observed compared to PP and PP/neat‐MWCNT. Especially, the decomposition temperature of the composite was increased by 50°C compared to PP. PP/MA‐g‐PP/diamine‐MWCNTs composite showed the highest complex viscosity. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

The effects of triethylenetetramine grafting of multi‐walled carbon nanotubes on its dispersion,filler‐matrix interfacial interaction and the thermal properties of epoxy nanocomposites

This study describes the influence of triethylenetetramine (TETA) grafting of multi‐walled carbon nanotubes (MWCNTs) on the dispersion state, interfacial interaction, and thermal properties of epoxy nanocomposites. MWCNTs were first treated by a 3:1 (v/v) mixture of concentrated H₂SO₄/HNO₃, and then TETA grafting was performed. Chemically grafted MWCNT/bisphenol‐A glycidol ether epoxy resin/2‐ethyl‐4‐methylimidazole nanocomposites were prepared. TETA grafting could establish the connection of MWCNTs to the epoxy matrix and transform the smooth and nonreactive MWCNT surface into a hybrid material that possesses the characteristics of both MWCNTs and TETA, which facilitates homogeneous dispersion of MWCNTs and improves nanotube‐epoxy interfacial interaction. Therefore, the impact property, glass transition temperature, thermal stability, and thermal conductivity of epoxy nanocomposites are enhanced. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers     

Amino functionalization of multiwalled carbon nanotubes by gamma ray irradiation and its epoxy composites

In this paper, γ‐ray radiation technique was utilized to simply functionalize multi‐walled carbon nanotube (MWCNT) with amino groups. The successful amino functionalization of MWCNTs (MWCNTs‐Am) was proven and the physicochemical properties of MWCNTs before and after radiation grafting modifications were characterized using FT‐IR, X‐ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The results indicated that the γ‐ray radiation had the visible effects on the surface properties of MWCNTs. The effects of various functionalized MWCNTs on morphological, thermal, and mechanical properties of an epoxy‐based nanocomposite system were investigated. Utilizing in situ polymerization, 1 wt% loading of MWCNT was used to prepare epoxy‐based nanocomposites. Compared to the neat epoxy system, nanocomposites prepared with MWCNT‐Am showed 13.0% increase in tensile strength, 20.0% increase in tensile modulus, and 24.1% increase in thermal decomposition temperature. POLYM. COMPOS., 2012. © 2011 Society of Plastics Engineers     

Positive temperature coefficient to resistively characteristics of polystyrene/nickel powder/multiwall carbon nanotubes composites

Positive temperature coefficient to resistivity (PTCR) characteristics of polystyrene (PS)/Ni‐powder (40 wt%) composites in the presence of multiwall carbon nanotubes (MWCNTs) has been investigated with reference to PS/carbon black (CB) composites. The PS/CB (10 wt%) composites showed a sudden rise in resistivity (PTC trip) at ≈110°C, above the glass transition temperature (T_g) of PS (T_g ≈95°C). Interestingly, the PTC trip temperature of PS/Ni‐powder (40 wt%)/MWCNT (0.75 phr) composites appeared at ≈90°C (below T_g of PS), indicating better dimensional stability of the composites at PTC trip temperature. The PTC trip temperature of the composites below the T_g of matrix polymer (PS) has been explained in terms of higher coefficient of thermal expansion (CTE) value of PS than Ni that led to a disruption in continuous network structure of Ni even below the T_g of PS. The dielectric study of PS/Ni‐powder (40 wt%)/MWCNT (0.75 phr) composites indicated possible use of the PTC composites as dielectric material. Dynamic mechanical analysis (DMA) and thermogravimetric analysis studies revealed higher storage modulus and improved thermal stability of PS/Ni‐powder (40 wt%)/MWCNT (0.75 phr) composites than the PS/CB (10 wt%) composites. POLYM. COMPOS., 33:1977–1986, 2012. © 2012 Society of Plastics Engineers