Multi-walled Carbon Nanotubes Loading Research Articles

Hysteretic damping in XNBR – MWNT nanocomposites at low and high compressive strains

In this study, compressive hysteretic damping properties of carboxylated nitrile rubber (XNBR) and its composites containing multiwalled carbon nanotubes (MWNT) were investigated at high strains by Universal Testing Machine (UTM) and at low strains by Dynamic Mechanical Analyzer (DMA). Degree of damping is less than the neat XNBR at low MWNT loading and it increases significantly at higher loading. At constant MWNT loading, the extent of damping depends on applied strain. Mullins effect is observed in both neat XNBR and composites due to the presence of ionic clusters. Differential Scanning Calorimetry (DSC) and X-ray diffraction analysis (XRD) confirm the reversible nature of the ionic cluster formation/deformation. Deformation of ionic clusters and nanotube agglomerates contribute to the overall increase in damping. Morphology characterization by Transmission Electron Microscope (TEM) reveals agglomeration of nanotubes at higher loading levels. A schematic diagram about the structural changes due to application of heat and stress is proposed. The results would be of great assistance in the design of application specific composites for various engineering applications.

Noncovalent compatibilization of polypropylene/MWCNT composites using an amino-pyridine grafted polypropylene matrix

Polypropylene (PP)/multiwalled carbon nanotube (MWCNT) composites are prepared by implementing noncovalent compatibilization. The compatibilization method involves PP matrix functionalization with pyridine (Py) aromatic moieties, which are capable of π–π interaction with MWCNT sidewalls. Imaging revealed that the addition of 25 wt% of PP-g-Py to neat PP is capable of drastically reducing nanotube aggregate size and amount, compared to a matrix containing the equivalent amount of a maleated PP (PP-g-MA). Raman spectroscopy confirms improved polymer/nanotube interaction with the PP-g-Py matrix. The electrical percolation threshold appears at a MWCNT loading of approximately 1.2 wt%, and the maximum value of the electrical conductivity achieved is 10−2 S/m, irrespective of the functionalization procedure. The modulus of the composites is improved with the addition of MWCNTs. Furthermore, composites functionalized with Py display significant improvements in composite ductility compared with their maleated counterparts because of the improved filler dispersion. POLYM. COMPOS., 2015. © 2015 Society of Plastics Engineers

Multiwalled carbon nanotube-filled ethylene acrylic elastomer nanocomposites: Influence of ionic liquids on the mechanical, dynamic mechanical, and dielectric properties

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

Excellent electromagnetic interference shielding and mechanical properties of high loading carbon-nanotubes/polymer composites designed using melt recirculation equipped twin-screw extruder

This paper describes for the first time a facile, scalable and commercially viable melt blending approach involving use of twin-screw extruder with melt recirculation provision, for uniform dispersion of up to 4.6vol% multiwall carbon nanotubes (MWCNTs) within polypropylene random copolymer (PPCP). Morphological characterization of PPCP/MWCNT nanoscale composites (NCs) was done using scanning electron microscopy and transmission electron microscopy, which show good dispersion of MWCNTs in the PPCP matrix even at high loadings and confirm the formation of true NCs. The improved dispersion leads to the formation of electrically conducting three dimensional networks of MWCNTs within PPCP matrix at very low percolation threshold (∼0.19vol%). The attainment of dc conductivity value of ∼10−3S/cm, tensile strength of ∼42MPa and good thermal stability for 4.6vol% MWCNTs loading NC along with electromagnetic interference (EMI) shielding effectiveness (SE) value of −47dB (>99.99% attenuation), demonstrate its potential for making light weight, mechanically strong and thermally stable EMI shields. These NCs also display specific SE value of ∼−51dBcm3/g which is highest among unfoamed polymer NCs.

High electromagnetic interference shielding with high electrical conductivity through selective dispersion of multiwall carbon nanotube in poly (ε‐caprolactone)/MWCNT composites

ABSTRACTThis study presents the preparation of electrically conducting poly(ε‐caprolactone) (PCL)/multiwall carbon nanotube (MWCNT) composites with very low percolation threshold (pc). The method involves solution blending of PCL and MWCNT in the presence of commercial PCL beads. The PCL beads were added into high viscous PCL/MWCNT mixture during evaporation of solvent. Here, the used commercial PCL polymer beads act as an ‘excluded volume’ in the solution blended PCL/MWCNT region. Thus, the effective concentration of the MWCNT dramatically increases in the solution blended region and a strong interconnected continuous conductive network path of CNT−CNT is assumed throughout the matrix phase with the addition of PCL bead which plays a crucial role to improve the electromagnetic interference shielding effectiveness (EMI SE) and electrical conductivity at very low MWCNT loading. Thus, high EMI SE value (∼23.8 dB) was achieved at low MWCNT loading (1.8 wt %) in the presence of 70 wt % PCL bead and the high electrical conductivity of ∼2.49×10−2 S cm−1 was achieved at very low MWCNT loading (∼0.15 wt %) with 70 wt % PCL bead content in the composites. The electrical conductivity gradually increased with increasing the PCL bead concentration, as well as, MWCNT loading in the composites. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42161.

Design and characterization of novel conductive nanocomposites based on carbon nanotube modified liquid crystalline epoxy

In this work, a series of novel isotropically conductive adhesives (ICAs) based on multiwalled carbon nanotube (MWCNT)-modified liquid crystalline epoxy (LCE) resin was prepared. Different loadings of MWCNTs were used to produce LCE composites. Transmission electron microscope, scanning electron microscope, differential scanning calorimetry, polarized light optical microscopy, X-ray diffraction, electrical conductivity measurement, and tensile and flexural measurements were used to characterize the morphology, thermal, phase change, electrical, and mechanical properties of the prepared composites. The results showed that the added MWCNTs were dispersed well in the LCE matrix. The introducing MWCNTs did not show any major influence on typical curing peaks of LCE. Electrical conductivity at room temperature of the composites was increased significantly compared with neat LCE. The conductivity value of 10−2 S cm−1 was obtained at a weight concentration of only 0.5% MWCNT. In addition, tensile strength, Young’s modulus, flexural strength, and flexural modulus of the composites were increased clearly compared with neat LCE matrix. These produced LCE composites with very low MWCNT loadings showed a great prospect of being used as ICAs.

Water Vapor Transport Enhancement Through Isotactic Polypropylene by Incorporating Multiwalled Carbon Nanotubes

In the present work, the incorporation of multiwalled carbon nanotubes (MWCNTs) in isotactic polypropylene (i-PP) was examined in terms of water vapor transport. The structure of the composites, as well as the MWCNT dispersion, was characterized by scanning electron microscopy, Raman spectroscopy, thermal analysis, and X-ray diffraction. Furthermore, broadband dielectric relaxation spectroscopy was employed to study the electrical properties of the nanocomposites. The composite membranes were prepared by a melt mixing procedure. The incorporation of MWCNTs resulted in a 12-fold increase in the specific water vapor transmission rate. Water vapor transport properties were found to be limited by efficient obstructive nanotube agglomerate formation for high MWCNT loadings.

Expanded graphite (EG) as a potential filler in the reduction of percolation threshold of multiwall carbon nanotubes (MWCNT) in the PMMA/HDPE/EG/MWCNT nanocomposites

A facile route for the development of a conducting hybrid polymer nanocomposites composed of poly(methyl methacrylate) (PMMA)/high density polyethylene (HDPE) filled with multiwall carbon nanotube (MWCNT) and expanded graphite (EG) has been described. The EG used in this study was prepared by simple chemical exfoliation of graphite flakes and characterized by spectroscopic as well as morphological analysis. An industrially feasible melt mixing process was used for the preparation of the nanocomposites through sequential heating protocol. The judicious control of temperature during mixing revealed a highly co‐continuous structure of HDPE throughout the PMMA matrix and thus the percolation of the (75/25, w/w) PMMA/HDPE/bi‐filler nanocomposites was achieved at 0.07 wt% loading of MWCNT. An extensive analysis revealed that the selective dispersion of the conductive bi‐filler in the minor HDPE phase helped in the reduction of the percolation threshold through MWCNT–EG–MWCNT networking. The morphology, electrical conductivity, and their interrelation of the prepared nanocomposites can be found in detail in the manuscript. POLYM. COMPOS., 37:2070–2082, 2016. © 2015 Society of Plastics Engineers

Effect of MWCNT loading on the morphological, optical and electrical properties of Nickel phtalocyanine based composites

We report on the investigation of the surface morphology, optical and electrical properties of nanocompsite films from multiwalled carbon nanotubes (MWCNT) dispersed in nickel phthalocyanine (NiPc) with different amounts. We have explored the surface morphology of the films by using fractal concepts. The NiPc:MWCNT films were found to have a fractal dimension of ca. 2, indicating a quasi Euclidean surface. An increase in the wetting contact angle of NiPc:MWCNT films with MWCNT concentrations was observed. AC conductivity and dielectric properties of NiPc:MWCNT nanohybrids were measured at 100Hz–13MHz at room temperature. Upon increasing the concentration of MWCNT an increase in the AC conductivity is observed. The variation of AC conductivity with frequency has been described by the power law. The introduction of the concept of Constant Phase Element into the equivalent circuit model gave a fit in good agreement with the experimental data and implied the influence of a fractal interface on the real capacitance. The evolution of the electrical parameters with frequency and bias voltage of these composite-based systems has been discussed. Finally, the optimum composite proportion for high electrode sensitivity was tested by means of the electrochemical impedance spectroscopy for detection of Bisphenol A.

Multi-walled carbon nanotube-coated cotton fabric for possible energy storage devices

A conducting cotton fabric with a resistance of <1.5 kΩ cm−2 was obtained by dip coating of multi-walled carbon nanotubes (MWCNTs) dispersed in a surfactant, sodium dodecyl sulphate (SDS). The dip coating was repeated up to 20 times to increase the loading of MWCNT as observed from optical absorption spectra (λmax = 442 nm). The field emission scanning electron microscopy (FE-SEM) image of coated fabric at different magnifications shows micro-fibril structure. Energy-dispersive X-ray analysis (EDXA) spectra show peaks for carbon and other constituent elements of SDS, Na and S. In order to improve the functionality of loaded MWCNT, the coated fabric was treated with 5% HNO3 for 3 h. For such a sample, the resistance decreased significantly to 1.5 kΩ cm−2, whereas it is 2.0 and 2.5 kΩ cm−2 for untreated and KOH-treated sample. This is in corroboration with I−V characteristics, and is attributed to increased loading of MWCNT through hydrogen bonding with glycosidic group present in cotton (cellulose) fibres. The series capacitance of the MWCNT-coated fabric is about 40 μF cm−2, which is found to decrease with the increase in frequency, close to zero at about 20 kHz. A capacitor formed by placing two MWCNT-coated fabrics between etched PCB plates (terminal contacts) shows the charging capacity of about 1 F.

Super Heat-Resistant Conductive Nanocomposites Based on Polysulfone–Carbon Nanofillers

The present article describes the morphology, mechanical, thermal, electrical, and dielectric properties of polysulfone (PSU) nanocomposites filled with different concentrations of multiwalled carbon nanotubes (MWCNT) and carbon nanofibers (CNF) [Only one carbon material per each]. The tensile strength and tensile modulus of both MWCNT- and CNF-filled nanocomposites increased with the increase in filler loading up to 3 wt.%. The addition of 3 wt.% CNF led to increase in tensile strength and modulus by 22% and 46%, respectively. Similarly at the same loading of MWCNT, the tensile strength and tensile modulus increased by 16% and 44%, respectively. Thermogravimetric analysis indicated continuous upgrade in thermal stability compared to pure PSU matrix up to 3 wt.% nanofiller loading. Electrical conductivity of both nanocomposites obeyed a power law model of the percolation theory having very low percolation threshold of 0.0079 (0.9 wt.%) for PSU/CNF nanocomposite and 0.014 (1.5 wt.%) for PSU/MWCNT nanocomposite. Dielectric properties of nanocomposites were enhanced significantly with increasing MWCNT/CNF concentration, but decreased with increasing frequency. The dielectric constant reached to 8.5 × 109 (100 Hz) at 5 wt.% MWCNT and 5.4 × 1010 at 5 wt.% CNF, respectively, from the neat PSU matrix (2.1 at 100 MHz). The current (I)–voltage (V) characteristics exhibited ohmic conduction at and above the percolation threshold for both MWCNT- and CNF-filled nanocomposites.

Enhancement of the electrochemical performance of LiFePO4/carbon nanotubes composite electrode for Li-ion batteries

LiFePO4 is very good potential cathode materials for the power lithium-ion batteries because of its high theoretical capacity and high voltage, but its electrochemical performance suffers from the low electronic conductivity. In this paper, the multi-walled carbon nanotubes (MWCNTs)/LiFePO4 composites cathode materials are prepared by ball milling. With high conductivity and the network structure existing in the LiFePO4 electrode, carbon nanotubes can reduce internal resistance and increase practical capacity and cycle stability of LiFePO4. As electrodes of lithium battery, the charge–discharge capacity, cyclic voltammetry, cycle life, alternating current impedance, and discharge temperatures characteristic of LiFePO4/MWCNTs (the loading of MWCNTs from 0 to 20 %) are investigated. The resistances of LiFePO4/MWCNTs decrease with the increase of MWCNTs loading and reach a minimal value of 56 Ω in the 10 % loading of MWCNTs, and result in the improvement of electrochemical performance. It is found that the composite electrode with 10 % loading of MWCNTs exhibits a best charge–discharge performance, and has initial charge capacities of 148 mAhg−1 and discharge capacities of 145 mAhg−1, respectively at 0.1 °C rate and the capacity retention is 98 %. The result of the pure LiFePO4 shows that the discharge capacity is 131 mAhg−1 at the rate of 0.5 °C, which means the increase in capacity of the LiFePO4/MWCNTs electrode achieves 16 %. The LiFePO4/MWCNTs composites also have perfectly high temperature performance due to the excellent thermal stability of the MWCNTs, and the discharge capacity of the composite electrode is 164 mAhg−1 at 0.1 °C rate in the temperature of 60 °C. After 30 cycles, the capacity still maintains as 163 mAhg−1 and the capacity retention is 99 %. The excellent cycle performance of the LiFePO4/MWCNTs electrode may attribute to the netlike-structure mechanical and electrical performance of MWCNTs.

Potential of Polarized PVDF/Carbon Nanotube Nanocomposite Scaffolds for Cell Growth

ABSTRACTWe investigated the effects of varying the multiwalled carbon nanotube (MWCNT) contents, as well as the additional use of drawing and poling on the polymorphic behavior and electroactive (piezoelectric) properties of the cast poly(vinylidene fluoride) (PVDF)/MWCNT membranes. Dramatic changes occurred in the polar β-phase crystal contents with the MWCNT loading. An optimum concentration of MWCNT exists for PVDF film polarization. On the other hand, films prepared by electrospinning process exhibited almost constant amount of β-phase with the MWCNT concentration. In this process, polymer fibers with diameters down to the nanometer range, or nanofibers, are formed by subjecting a fluid jet to a high electric field. The remanent polarization and piezoelectric response increased with the β-phase crystals. Cell adhesion and proliferation measured with MTT (Methylthiazolyl diphenyl-tetrazolium bromide) assay coincidentally responded to the polarized PVDF films (β-phase amount).

Studies of Electrical and Thermal Conductivities of Sheared Multi-Walled Carbon Nanotube with Isotactic Polypropylene Polymer Composites

Polymer nanocomposite materials of higher thermal and electrical transport properties are important to nanotechnology applications such as thermal management, packaging, labelling and the textile industry. In this work, thermal and electrical conductivities in nanocomposites of multiwalled carbon nanotubes (MWCNT) and isotactic polypropylene (iPP) are investigated in terms of MWCNT loading, temperature dependence, and anisotropy caused by melt shearing. IPP/MWCNT nanocomposites show a significant increase in thermal and electrical conductivity with increasing MWCNT loading, reaching 17.5 W/m K and 10−6 S/m, respectively, at a MWCNT 5.0 weight percentage at 40°C. The increase in MWCNT/iPP is more than would be expected based on the additivity rule, and suggests a reduction of the interfacial thermal electrical resistance at nanotube-nanotube junctions and the nanotube-matrix interface. The anisotropy in both conductivities was observed to be larger at low temperature and to disappear at higher temperature due to isotropic electrical and thermal contact in both directions. Oriented MWCNT/iPP nanocomposites exhibit higher electrical and thermal conductivities, attributed primarily by orientation of nanotubes due to the shearing fabrication process.

Fabric Nanocomposite Resistance Temperature Detector

This paper illustrates the characterization of a fabric resistance temperature (RTD) detector made from electrospun nylon-6 functionalized with multiwalled carbon nanotubes (MWCNTs) and polypyrrole (PPy) for use in supracutaneous applications like smart clothing, prosthetic sockets, and other medical devices where a temperature detecting fabric is better suited than a rigid detector. The nanocomposite material acts like a RTD, because the conductivity increases linearly with temperature. The empirically determined temperature coefficient of resistance (TCR) is reported for this material, and is -0.204 ± 0.008%/C. Development of a simple and scalable process for constructing the detector utilized electrospinning nylon-6 as a membrane style substrate, vacuum filtration of MWCNTs onto the nylon scaffold, and vapor phase polymerization of pyrrole to PPy onto the MWCNT functionalized nylon nanofibers. The optimal loading of MWCNTs is 6.6 wt%. The conductivity of the device follows a percolative behavior and TCR values indicate this is a viable option for temperature detection. Resistance decreases with increasing temperature, which indicates this is a negative TCR material.

Electrical conduction and rheological behaviour of composites of poly(ε-caprolactone) and MWCNTs

Two mechanisms of conduction were identified from temperature dependent (120 K–340 K) DC electrical resistivity measurements of composites of poly(ε-caprolactone) (PCL) and multi-walled carbon nanotubes (MWCNTs). Activation of variable range hopping (VRH) occurred at lower temperatures than that for temperature fluctuation induced tunneling (TFIT). Experimental data was in good agreement with the VRH model in contrast to the TFIT model, where broadening of tunnel junctions and increasing electrical resistivity at T > Tg is a consequence of a large difference in the coefficients of thermal expansion of PCL and MWCNTs. A numerical model was developed to explain this behavior accounting for a thermal expansion effect by supposing the large increase in electrical resistivity corresponds to the larger relative deformation due to thermal expansion associated with disintegration of the conductive MWCNT network. MWCNTs had a significant nucleating effect on PCL resulting in increased PCL crystallinity and an electrically insulating layer between MWCNTs. The onset of rheological percolation at ∼0.18 vol% MWCNTs was clearly evident as storage modulus, G′ and complex viscosity, |η*| increased by several orders of magnitude. From Cole–Cole and Van Gurp-Palmen plots, and extraction of crossover points (Gc) from overlaying plots of G′ and G″ as a function of frequency, the onset of rheological percolation at 0.18 vol% MWCNTs was confirmed, a similar MWCNT loading to that determined for electrical percolation.

Microwave absorption properties of multi-walled carbon nanotube (outer diameter 20–30 nm)–epoxy composites from 1 to 26.5 GHz

In this work, multi-walled carbon nanotube (MWCNT) (outer diameters (OD) in the range of 20–30nm)–epoxy composites were fabricated. The MWCNT loadings in the polymer composites were controlled from 1–10wt.%. An Agilent PNA Network analyzer was utilized in the measurements of microwave absorption (MA) properties of these MWCNT–epoxy composites over a wide frequency range of 1–26.5GHz. The measurement results showed that MA strongly depends on MWCNT loadings in the composites. In addition, the microwave reflection, transmission, and dielectric permittivity of the MWCNT–epoxy composites are also investigated. The composite with 8wt.% MWCNT loading shows high microwave absorption as well as low reflection and transmission. These MWCNT–epoxy composites with 8–10wt.% MWCNT loadings show a significant potential for microwave technology applications.

Fabrication and origin of high-k carbon nanotube/epoxy composites with low dielectric loss through layer-by-layer casting technique

The distribution of polarized space charges and their relaxation behavior in high dielectric constant electric conductor/polymer composites are main factors that determine the frequency-dependent dielectric constant and dielectric loss. However, few reports focus on this motif. We present here the dielectric performance and mechanism of a unique kind of composites with multi-layers (coded as [MWCNT/EP]x, where x refers to the number of layers), fabricated by using layer-by-layer casting technique. Each composite layer with same thickness was composed of multi-walled carbon nanotubes (MWCNTs) and epoxy (EP) resin. When the loading of MWCNTs is 0.5wt%, the four-layer [MWCNT0.5/EP]4 material shows the highest dielectric constant (465 at 1Hz) and low dielectric loss tangent (0.7 at 1Hz), about 4 and 2.1×10−2 times the values of traditional MWCNT0.5/EP composite, respectively. By investigating the space charge polarization (SCP), Debye polarization and dielectric moduli in [MWCNT/EP]x materials, the complex relationships and the origin among dielectric constant, dielectric loss, frequency and the content of filler were clearly elucidated. The SCP within each layer is different from that between layers. The greatly improved dielectric properties of [MWCNT/EP]x materials are believed to be the reinforced SCP and blocked transport of carriers between every two layers.

Effect of glass fiber on the electrical resistivities of polyoxymethylene/maleic anhydride‐grafted polyethylene/multiwalled carbon nanotube composites

ABSTRACTThe effect of glass fiber (GF) on the electrical resistivities of polyoxymethylene (POM)/maleic anhydride‐grafted polyethylene (MAPE)/multiwalled carbon nanotube (MWCNT) composites is investigated. The POM/MAPE/MWCNT composites at a MWCNT loading of 0.75% are nonconductive because most of MWCNTs are isolated in the MAPE islands, and their electrical resistivities decrease significantly after the addition of GF because of the formation of MAPE‐coated GF structure, which facilitates the formation of conductive paths and was confirmed by field emission scanning electron microscopy (FESEM). The formation of MAPE‐coated GF structure is attributed to the interaction between GF and MAPE during melt compounding, as contrasted by the uncoated GF using high‐density polyethylene (HDPE) instead of MAPE. Nonconductive POM/5–20% MAPE/0.75% MWCNT composites become conductive upon the addition of 20% GF. This preparation method for conductive materials can be generalized to POM/5–20% maleic anhydride‐grafted polypropylene (MAPP)/0.75% MWCNT composites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41794.

Multi-walled carbon nanotube/PVDF blended membranes with sponge- and finger-like pores for direct contact membrane distillation

Polyvinylidene fluoride (PVDF) flat sheet membranes were blended with multi-walled carbon nanotubes (MWCNTs) by the phase inversion method for direct contact membrane distillation (DCMD) of salty water (35gL−1 NaCl). The membrane properties and performances depended markedly on the synthesis parameters such as MWCNT loading, polyvinylpyrrolidone (PVP) addition and MWCNT surface chemistry. MWCNT/PVDF membranes prepared with functionalized MWCNTs have a smaller pore size (determined by bubble point measurements) and lower contact angles, thus, functionalization of MWCNTs is not recommended for this application. For membranes presenting the same pore size, the pore morphology and the membrane thickness are crucial for efficient salt rejection. Sponge-like pores and the smallest possible thickness (i.e., membranes prepared without PVP) allow complete salt rejection (i.e., 100%), in contrast with larger thickness and elongated finger-like pores (resulting from PVP addition) whose salt exclusion ranged from 88.8 to 98.6%. Overall, the MWCNT/PVDF blended membrane prepared with 0.2wt.% optimal content of pristine MWCNTs (without adding PVP) exhibited the best performance in DCMD, presenting total salt rejection and a higher permeate flux (9.5×10−3kgm−2s−1) than that obtained with a commercial PVDF membrane (7.8×10−3kgm−2s−1).