Statistical analysis of nanofibers alignment in magnetic‐field‐assisted electrospinning including an alignment percentage formula

Magnetic‐field‐assisted electrospinning (MFAES) is a simple and effective method to align polymer nanofibers. In this method, further research is needed to identify alignment mechanism. Hence, this article includes statistical analysis of affecting factors to investigate alignment mechanism in MFAES. Tip to target distance, magnets distance, voltage, and collection time, which are recognized as the most effective factors on nanofibers alignment, were applied in design of experiments. Central composite method was applied to get required experiments with designed expert 8 software. A response surface was proposed with regression coefficient of 97%. Then, the common physics concepts and statistical results were used to discuss the affecting mechanism of the electric and magnetic fields on the electrospinnig jet and the nanofibers alignment. Field emission scanning electron microscopy images were used to characterize the nanofibers alignment and calculate overall alignment percentage using a proposed statistical combinatorial weighted percentage formula. MFAES method, used in this research, achieved 95.3% polyacrylonitrile‐aligned nanofibers. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41179.     

Densifying and strengthening of electrospun polyacrylonitrile‐based nanofibers by uniaxial two‐step stretching

The effects of alignment of polyacrylonitrile (PAN) nanofibers and a two‐step drawing process on the mechanical properties of the fibers were evaluated in the current study. The alignment was achieved using a high‐speed collector in electrospinning synthesis of the nanofibers. Under optimal two‐step drawing conditions (e.g., hot‐water and hot‐air stretching), the PAN nanofiber felts exhibited large improvements in both alignment and molecular chain‐orientation. Large increase in crystallinity, crystallite size, and molecular chain orientation were observed with increasing draw ratio. Optimally, stretched PAN‐based nanofibers exhibited 5.3 times higher tensile strength and 6.7 times higher tensile modulus than those of the pristine one. In addition, bulk density of the drawn PAN nanofibers increased from 0.19 to 0.33 g/cm³. Our results show that fully extended and oriented polymer chains are critical in achieving the highest mechanical properties of the electrospun PAN nanofibers. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43945.     

Polyvinylbutyral‐assisted synthesis and characterization of SnS mesoporous fibers via electrospinning process

Tin sulfide (SnS) has the potential to be used as a low‐cost absorber material for applications in thin film photovoltaic solar cells. In this study, polyvinylbutyral/SnS (PVB/SnS) composite fibers were synthesized through a relatively simple electrospinning process. SnS mesoporous fibers were obtained from PVB/SnS composite fibers after sintering treatment at 500°C for 1 h in N₂ atmosphere. The SnS mesoporous fibers were then characterized using X‐ray powder diffraction, scanning electron microscopy, thermogravimetric analysis, and transmission electron microscopy. The optical properties of SnS mesoporous fibers were also recorded by UV–vis absorption spectroscopy. The results showed that the synthesized SnS mesoporous fibers exhibited a single phase, stoichiometric composition, with good crystallinity, a size ranging from 100 to 200 nm, and a band gap of 1.49 eV. The as‐prepared SnS mesoporous fibers are thus a suitable material to achieve visible light absorption in a thin film solar cell. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42388.     

Secondary dopants modified PEDOT‐sulfonated poly(imide)s for high‐temperature range application

Poly(3,4‐ethylenedioxythiophene) (PEDOT) was polymerized using sulfonated poly(amic acid)s templates (SPAA1 and SPAA2) by batch operation. The new method was invented to enhance conductivities (ca. 100 ‐ to 2000‐fold) and with less reaction time from previous work (7 days vs. 3 days). Moreover, to increase the conductivity, many dopants were introduced as secondary doping compared with DMF, D ‐sorbitol, and surfynol that were previously used. After annealing at 180°C for 10 min, PEDOT‐SPAA1 and PEDOT‐SPAA2 doped with benzo‐1,4‐dioxan and quinoxaline showed the increase in conductivity by higher percentage than any other systems, especially doped with D ‐sorbitol and surfynol. These showed the promising tendency to develop the annealing activated superior conductivity materials after further modifying the conducting film forming processes. However, PEDOT‐SPAAs doped with benzo‐1,4‐dioxan, imidazole and quinoxaline via annealed at 180°C for 10 min were found to be more conductive than doped with DMF, but still lower conductive than doped with D ‐sorbitol and surfynol. In terms of particle size, the stable aqueous dispersions of conducting polymers prepared were comparable to polystyrene sulfonate template. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Fabrication and characterization of double‐network agarose/polyacrylamide nanofibers by electrospinning

This study focused on the preparation of electrospun cross‐linked double‐network (DN) of agarose/polyacrylamide (PAAm) nanofibers. The agarose formed the first‐network that was physical‐linked by the agar helix bundles. After UV‐irradiation, the chemically crosslinked PAAm was formed as the second network. The resulting cross‐linked DN agarose/PAAm nanofibers were characterized by scanning electron microscopy (SEM), contact angle, attenuated total reflectance‐Fourier transform infrared spectroscopy (ATR‐FT‐IR), thermogravimetric analysis (TGA), and tensile test. SEM analysis shows the agarose/PAAM nanofibers present with the thickness of 187 nm. Agarose/PAAm nanofibers were showing FT‐IR spectral peaks at ～1660, 1590, and 1070 cm^?1 indicating the presence of both agarose and polyacrylamide in the crosslinked DN Agarose/PAAm nanofiber sheet, it suggests the strong interaction and good compatibility between the two components. Agarose/PAAm nanofiber sheet was showing thermal stability close to the pure polyacrylamide. From the tensile test study, agarose/PAAm strength improved by 66.66% compared to the pure agarose. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42914.     

Multiple conjugate electrospinning method for the preparation of continuous polyacrylonitrile nanofiber yarn

Continuous polyacrylonitrile nanofiber yarns were fabricated by the homemade multiple conjugate electrospinning apparatus, and the principle of yarn spinning was studied. The effects of the applied voltage, flow rate, spinning distance, and funnel rotary speed on the diameter and mechanical properties of nanofiber yarn were analyzed. The diameter of the nanofibers decreased with increasing applied voltage and the flow rate ratio of the positive and negative needles (F_P/F_N), whereas the diameter of nanofibers increased with increasing overall flow rate and needle distance between the positive and negative. Subsequently, the diameter of the yarns increased first and then decreased with increasing applied voltage, F_P/F_N, and needle distance. However, the diameters of the yarns increased dramatically and then remained stable with increasing overall flow rate. The nanofibers were stably aggregated and continuously bundled and then uniformly twisted into nanofiber yarns at an applied voltage of 20 kV, an overall flow rate of 6.4 mL/h, a needle distance of 18.5 cm, and an F_P/F_N value of 5:3. With increasing funnel rotary speed, the diameters of the nanofibers and yarns decreased, whereas the twist angle of the nanofiber yarns gradually enlarged. Meanwhile, an increase in the twist angle brought about an improvement in the yarn mechanical properties. Nanofiber yarns that prepared showed diameters between 70 and 216 μm. Nanofiber yarns with a twist angle of 65° showed a tensile strength of 50.71 MPa and an elongation of 43.56% at break, respectively. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40137.     

Fabrication and characterization of food‐grade fibers from mixtures of maltodextrin and whey protein isolate using needleless electrospinning

Food‐grade fibers were fabricated from dispersions of maltodextrin and whey protein isolate (WPI) using needleless electrospinning. Two maltodextrins (DE 2) from different starch sources were used and the maltodextrin/WPI ratio was varied. Molecular weight, intrinsic viscosity, entanglement concentration, shear stability, and electrical conductivity were studied as function of maltodextrin type and mixing ratio and correlated to fiber production rate and morphology. The results show that a high molecular weight of the maltodextrin was beneficial to its spinnability. Waxy potato starch maltodextrin (P‐MD) (M_w = 129.6 kDa) and WPI produced fibers with diameters between 1.40 and 1.67 µm at production rates up to 1.65 g/h; while the dispersions with waxy maize starch maltodextrin (M‐MD) (M_w = 85.9 kDa) showed poor spinnability and ruptured fibers. P‐MD/WPI dispersions had a higher viscosity and stronger shear thinning behavior attributed to a stronger entangled polymer network which is beneficial to electrospinning. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46328.     

Preparation and characterization of thermoplastic antistatic polyurethane synthesized by in situ polymerization

Antistatic polyurethane (APU) is prepared by in situ polymerization of polyester glycol (PEL), 4,4′‐diphenylmethane diisocyanate (MDI), 1,4‐butanediol (BDO), and antistatic agent (AA) formed by dissolving sodium salts in polyethylene glycol (PEG). Comprehensive properties of the APU are investigated by the FT‐IR, mechanical characterization, surface resistivity measurement, relative humidity (RH) study, and TGA, respectively. It is found that the surface resistivity of the APU can be effectively reduced to 10^9.15 Ω, showing a good antistatic property. Moreover, the APU maintains a low surface resistivity (～10^9.43 Ω) at the RH of 0.1%, revealing a non‐RH‐sensitive capacity of the APU. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39921.     

Electrospinning core‐shell nanofibers for interfacial toughening and self‐healing of carbon‐fiber/epoxy composites

This article reports a novel hybrid multiscale carbon‐fiber/epoxy composite reinforced with self‐healing core‐shell nanofibers at interfaces. The ultrathin self‐healing fibers were fabricated by means of coelectrospinning, in which liquid dicyclopentadiene (DCPD) as the healing agent was enwrapped into polyacrylonitrile (PAN) to form core‐shell DCPD/PAN nanofibers. These core‐shell nanofibers were incorporated at interfaces of neighboring carbon‐fiber fabrics prior to resin infusion and formed into ultrathin self‐healing interlayers after resin infusion and curing. The core‐shell DCPD/PAN fibers are expected to function to self‐repair the interfacial damages in composite laminates, e.g., delamination. Wet layup, followed by vacuum‐assisted resin transfer molding (VARTM) technique, was used to process the proof‐of‐concept hybrid multiscale self‐healing composite. Three‐point bending test was utilized to evaluate the self‐healing effect of the core‐shell nanofibers on the flexural stiffness of the composite laminate after predamage failure. Experimental results indicate that the flexural stiffness of such novel self‐healing composite after predamage failure can be completely recovered by the self‐healing nanofiber interlayers. Scanning electron microscope (SEM) was utilized for fractographical analysis of the failed samples. SEM micrographs clearly evidenced the release of healing agent at laminate interfaces and the toughening and self‐healing mechanisms of the core‐shell nanofibers. This study expects a family of novel high‐strength, lightweight structural polymer composites with self‐healing function for potential use in aerospace and aeronautical structures, sports utilities, etc. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Fabrication of superhydrophobic fiber coatings by DC‐biased AC‐electrospinning

Mesh‐like fiber mats of polystyrene (PS) were deposited using DC‐biased AC‐electrospinning. Superhydrophobic surfaces with water contact angles greater than 150° and gas fraction values of up to 97% were obtained. Rheological study was conducted on these fiber surfaces and showed a decrease in shear stress when compared with a noncoated surface (no slip), making them excellent candidates for applications requiring the reduction of skin‐friction drag in submerged surfaces. We have also shown that addition of a second, low‐surface energy polymer to a solution of PS can be used to control the fiber internal porosity depending on the concentration of the second polymer. Contact‐angle measurements on mats consisting of porous and nonporous fibers have been used to evaluate the role of the larger spaces between the fibers and the pores on individual fibers on superhydrophobicity. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

POSS‐based fluorinated azobenzene‐containing polymers: Photo‐responsive behavior and evaluation of water repellency

The photoresponsive polyhedral oligomeric silsesquioxanes (POSS) based fluorinated azobenzene‐containing polymers were prepared and characterized by NMR, FT‐IR, GPC, XRD, TG and UV–Vis spectra. The thermal property of the polymers was improved by the introduction of POSS cage. The trans‐cis photoisomerization of the polymers in solution was similar to that of the fluorinated azobenzene monomer and in accordance with the first‐order reaction kinetics equation within the first 250 seconds UV irradiation. The cotton fabrics coated with the polymers showed excellent water repellency and possessed switchable wettability under UV irradiation. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43540.     

Self‐healing and interfacially toughened carbon fibre‐epoxy composites based on electrospun core–shell nanofibres

Dual components of a self‐healing epoxy system comprising a low viscosity epoxy resin, along with its amine based curing agent, were separately encapsulated in a polyacrylonitrile shell via coaxial electrospinning. These nanofiber layers were then incorporated between sheets of carbon fiber fabric during the wet layup process followed by vacuum‐assisted resin transfer molding to fabricate self‐healing carbon fiber composites. Mechanical analysis of the nanofiber toughened composites demonstrated an 11% improvement in tensile strength, 19% increase in short beam shear strength, 14% greater flexural strength, and a 4% gain in impact energy absorption compared to the control composite without nanofibers. Three point bending tests affirmed the spontaneous, room temperature healing characteristics of the nanofiber containing composites, with a 96% recovery in flexural strength observed 24 h after the initial bending fracture, and a 102% recovery recorded 24 h after the successive bending fracture. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44956.     

Nanostructured star‐shaped polythiophene with tannic acid core: Synthesis,characterization, and its physicochemical properties

For the first time, synthesis and characterization of a nanostructured star‐shaped polythiophene (PTh) with tannic acid core by both chemical and electrochemical oxidation polymerization methods through a “core‐first” method is reported. The chemical structures of all samples as representatives were characterized by means of Fourier transform infrared (FTIR), and ¹H nuclear magnetic resonance (NMR) spectroscopies. The electroactivity behaviors of the synthesized samples were verified under cyclic voltammetric conditions, and their conductivities were determined using the four‐probe technique. The synthesized star‐shaped PTh showed higher electrical conductivity and electroactivity than those of the PTh in both chemical and electrochemical polymerized samples, due to its large surface area, spherical, and three‐dimensional structure. Moreover, the thermal behaviors, optical properties, and morphologies of the synthesized samples were investigated by means of thermogravimetric analysis (TGA), ultraviolet–visible (UV–Vis) spectroscopy, and field emission scanning electron microscopy (FE‐SEM), respectively. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43513.     

Synthesis and characterization of a ferrocene‐modified,polyaniline‐like conducting polymer

A novel monomer called 1,1′‐ferrocenediacyl anilide (FcA) was synthesized from ferrocene (Fc). Copolymerization was carried out between FcA and aniline (ANI) by an electrochemical method. The novel monomer and copolymer were characterized with ¹H‐NMR, Fourier transform infrared (FTIR) spectroscopy, and ultraviolet–visible (UV–vis) spectroscopy. The hydrogen protons of the benzene ring were moved to a low field in ¹H‐NMR, and the absorption band of N?Q?N (where Q is the quinoid ring) appeared in the FTIR spectrum of the polymer. The peaks of both Fc and the π–π* electronic transition in the UV–vis spectra were redshifted. The results indicate that the copolymer mainly existed as a highly delocalized conjugated system. X‐ray diffraction analysis established further proof, and the process of electrochemical deposition was observed by scanning electron microscopy. The optimal synthesis conditions of the copolymer were determined through changes in the monomer molar ratios and the scan rate. The ideal performance of the copolymer was gained when the monomer molar ratio between FcA and ANI was 1:4 and the scan rate was 50 mV/s. Furthermore, the electrochemical performances were tested in detail by cyclic voltammetry, galvanostatic charge–discharge testing, and electrochemical impedance spectroscopy. The results show that the specific capacitance of poly(1,1′‐ferrocenediacyl anilide‐co‐aniline) increased up to 433.1 F/g at 0.5 A/g, the diffusion resistance was very small, and the durability was good enough. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43217.     

A comprehensive study on Plantago ovata/PVA biocompatible nanofibers: Fabrication,characterization, and biological assessment

In this study, a biocompatible nanofiber is fabricated using Plantago ovata mucilage (POM) combined with polyvinyl alcohol (PVA), which is considered as a non-toxic polymer. High quality nanofibers were produced by controlling the electrospinning parameters after selecting an appropriate solvent for the POM/PVA combination (12% PVA and 3% POM). Electrospinning parameters, including high voltage, distance from collector to tip, feed rate and POM to PVA proportion were optimized following preparation of an aqueous POM/PVA solution. Using the results of scanning electron microscopy, the optimized electrospinning conditions for producing POM/PVA nanofibers were determined (high voltage = 18 kV, distance = 15 cm, feed rate = 0.125 ml/hr, PMM/PVA = 50/50) and uniform nanofibers with an average diameter of 250 nm were produced. The POM/PVA nanofiber sample was evaluated by determining the mechanical strength, characterization of produced nanofiber morphology, and investigating the cell viability by applying MTT assay. The bands for both POM and PVA from FTIR results showed that the samples remained stable. The tensile strength results showed that blending POM with PVA solution enhanced the Young's modulus by factor of 3.2 (0.2 MPa to 0.64 MPa). The MTT analysis on POM/PVA cell lines proved that the produced nanofiber considerably enabled the cellular proliferation. Enhancement in these analysis indicated how POM-based nanofibers is a promising scaffold for cell culture, drug delivery systems and food additives.     

Reversibly thermochromic and high strength core-shell nanofibers fabricated by melt coaxial electrospinning

Recent years, phase change materials (PCMs) with potential to store and transform energy have attracted broad attention, especially in the field of thermal energy storage. However, the instability and leak proneness of PCMs limit their universal application. In this paper, core-shell fibers with 1-tetradecanol (TD) as core and poly(vinylidene fluoride) (PVDF) as shell were prepared via melt coaxial electrospinning method, and for improvement, the dye composed of crystal violet lactone (CVL) and bisphenol A (BPA) was added to the core to endow the fiber the function of reversible thermochromism. During the preparation process, it was found that the addition of NaCl could regulate the fiber morphology and strength its mechanical property. By adjusting the concentration of shell solution and the flow rate of core solution, the high-strength reversible thermochromic fibers were produced when polymer concentration was 24 wt% with a core feed rate of 0.4 ml/h. The latent heat of these fibers is up to 88.71 J/g. Besides, its color can change from blue to white when heated, and the transition temperature is around 38°C. And 100 thermal cycle tests of the fiber showed its strong thermal stability and thermochromic property.     

Nanostructured membranes based on cellulose acetate obtained by electrospinning. Part II. Controlled release profile and microbiological behavior

Nanofiber membranes of cellulose acetate (CA) were produced with four mixtures of solvents, that is, acetic acid/water, acetone/water, dimethylacetamide (DMAc)/acetone, and DMAc/acetone/water, with the incorporation of the drug gentamicin sulfate at two concentrations. We evaluated the influence of the drug concentration in the electrospinning process. The best membrane produced in this stage was the membrane electrospun with the DMAc/acetone/water solvent mixture, whose process was shown to be viable and did not alter the membrane diameter or aspect with the variation of the drug concentration. Membranes prepared in this way and loaded with 50% of the drug were used for the studies of the release kinetics. Comparisons between the release profiles of the same membranes coated with hydroxypropyl methylcellulose, Eudragit L100, and electrospun CA nanofibers were carried out. The best results on the drug‐release profile were obtained with the membrane coated with nanofibers of CA, which caused a decrease of 9 h in the burst effect. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2772–2779, 2013     

Thermal conductivity of polyimide/boron nitride nanocomposite films

The thermal conductivity of polyimide/boron nitride (PI/BN) nanocomposite thin films has been studied for two sizes of BN nanofillers (40 and 120 nm) and for a wide range of content. A strong influence of BN particle size on the thermal conduction of PI has been identified. In the case of the largest nanoparticles (hexagonal‐BN), the thermal conductivity of PI/h‐BN (120 nm) increases from 0.21 W/mK (neat PI) up to 0.56 W/mK for 29.2 vol %. For the smaller nanoparticles (wurtzite‐BN), PI/w‐BN (40 nm), we observed two different behaviors. First, we see a decrease until 0.12 W/mK for 20 vol % before increasing for higher filler content. The initial phenomenon can be explained by the Kapitza theory describing the presence of an interfacial thermal resistance barrier between the nanoparticles and the polymer matrix. This is induced by the reduction in size of the nanoparticles. Modeling of the experimental results allowed us to determine the Kapitza radius a_K for both PI/h‐BN and PI/w‐BN nanocomposites. Values of a_K of 7 nm and >500 nm have been obtained for PI/h‐BN and PI/w‐BN nanocomposite films, respectively. The value obtained matches the Kapitza theory, particularly for PI/w‐BN, for which the thermal conductivity is expected to decrease compared to that of neat PI. The present work shows that it seems difficult to enhance the thermal conductivity of PI films with BN nanoparticles with a diameter <100 nm due to the presence of high interfacial thermal resistance at the BN/PI interfaces. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42461.     

Preparation and characterizations of superparamagnetic iron oxide‐embedded poly(2‐hydroxyethyl methacrylate) nanocarriers

The present study aims at formulating a novel multifunctional biocompatible superparamagnetic nanoparticles carrier system with homogeneously dispersed magnetic material in solid polymer matrix of poly(2‐hydroxyethyl methacrylate) (PHEMA). The nanocomposites were designed by modified suspension polymerization of 2‐hydroxyethyl methacrylate followed by in situ coprecipitation of iron oxide inside the nanoparticle matrix yielding magnetic PHEMA (mPHEMA) nanocomposites. The so prepared nanocomposites were characterized by Fourier transform Infrared spectroscopy, X‐ray diffraction technique, Raman spectroscopy, electron diffraction, and energy‐dispersive X‐ray spectroscopy confirming the presence of Fe₃O₄ inside the PHEMA nanoparticles. The magnetization studies of nanocomposites conducted at room temperature using vibrating sample magnetometer suggested for their superparamagnetic nature having saturation magnetization (Ms) of 20 emu/g at applied magnetic field of 5 kOe. Transmission electron microscopy, field‐emission scanning electron microscopy, and dynamic light scattering/zeta potential measurements were also performed which revealed that size of mPHEMA nanocomposites was lying in the range of 60–300 nm having zeta potential of ?93 mV. The nanocomposites showed no toxicity as revealed by cytotoxicity test performed on L‐929 fibroblast by extract method. The results indicated that the prepared superparamagnetic mPHEMA nanocomposites have enormous potential to provide a possible option for magnetically assisted targeted delivery of anticancer drugs. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40791.     

Synthesis and characterization of LiFePO4–carbon nanofiber–carbon nanotube composites prepared by electrospinning and thermal treatment as a cathode material for lithium‐ion batteries

Binder‐free LiFePO₄–carbon nanofiber (CNF)–multiwalled carbon nanotube (MWCNT) composites were prepared by electrospinning and thermal treatment to form a freestanding conductive web that could be used directly as a battery cathode without addition of a conductive material and polymer binder. The thermal decomposition behavior of the electrospun LiFePO₄ precursor–polyacrylonitrile (PAN) and LiFePO₄ precursor–PAN–MWCNT composites before and after stabilization were studied with thermogravimetric analysis (TGA)/differential scanning calorimetry and TGA/differential thermal analysis, respectively. The structure, morphology, and carbon content of the LiFePO₄–CNF and LiFePO₄–CNF–MWCNT composites were determined by X‐ray diffraction, high‐resolution transmission electron microscopy, Raman spectroscopy, scanning electron microscopy, and elemental analysis. The electrochemical properties of the LiFePO₄–CNF and LiFePO₄–CNF–MWCNT composite cathodes were measured by charge–discharge tests and electrochemical impedance spectroscopy. The synthesized composites with MWCNTs exhibited better rate performances and more stable cycle performances than the LiFePO₄–CNF composites; this was due to the increase in electron transfer and lithium‐ion diffusion within the composites loaded with MWCNTs. The composites containing 0.15 wt % MWCNTs delivered a proper initial discharge capacity of 156.7 mA h g^?1 at 0.5 C rate and a stable cycle ability on the basis of the weight of the active material, LiFePO₄. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43001.