Hydroxyl-functionalized Multi-walled Carbon Nanotubes Research Articles

Enhancement of flame spread and droplet dynamics behavior of biodiesel constituents with ethanol and MWCNT-OH additions

The interactive droplet combustion between three adjacent droplets of biodiesel constituents was investigated to obtain flame spread and droplet dynamics behavior enhancement with ethanol and hydroxyl-functionalized multi-walled carbon nanotubes (MWCNT-OH) additives. The experiment was conducted at atmospheric pressure and under normal gravity using spatial and temporal tracking. This study found that ethanol effectively increases flame spread velocity and shortens droplet heating time at a close droplet distance. Meanwhile, MWCNT-OH shortens flame spread induction time at a large droplet distance when thermal conduction time mainly controls the flame spread. Both additives improve the volatility and thermal conductivity of fuel blends, extending the flame spread limit distance with strong reciprocal interaction between droplets and accelerating combustion with a higher burning rate. Different flame spread mechanisms were observed and determined by the fuel additives. Child droplet ejection and microburst flame encourage rapid ignition and flame spread to the next unburned droplet. The puffing and microexplosion mechanisms of the fuel blends were determined by the nucleation type preceding the child droplet ejection. Combining ethanol and MWCNT-OH as fuel additives is the most effective way to improve combustion and flame spread performance because ethanol induces nanoparticle burns at the earlier combustion stage.

Novel PEG6000-Silica-MWCNTs Shape-Stabilized Composite Phase-Change Materials (ssCPCMs) for Thermal-Energy Storage.

This paper describes the preparation of new PEG6000-silica-MWCNTs composites as shape-stabilized phase change materials (ssPCMs) for application in latent heat storage. An innovative method was employed to obtain the new organic-inorganic hybrid materials, in which both a part of the PEG chains, used as the phase change material, and a part of the hydroxyl functionalized multiwall carbon nanotubes (MWCNTs-OH), used as thermo-conductive fillers, were covalently connected by newly formed urethane bonds to the in-situ-generated silica matrix. The study's main aim was to investigate the optimal amount of PEG6000 that can be added to the fixed sol-gel reaction mixture so that no leakage of PEG occurs after repeated heating-cooling cycles. The findings show that the optimum PEG6000/NCOTEOS molar ratio was 2/1 (~91.5% PEG6000), because both the connected and free PEG chains interacted strongly with the in-situ-generated silica matrix to form a shape-stabilized material while preserving high phase-transition enthalpies (~153 J/G). Morphological and structural findings obtained by SEM, X-ray and Raman techniques indicated a distribution of the silica component in the amorphous phase (~27% for the optimum composition) located among the crystalline lamellae built by the folded chains of the PEG component. This composite maintained good chemical stability after a 450-cycle thermal test and had a good storage efficiency (~84%).

Compare Performance MWCNT-OH Network as a Gas Sensor of Embedded Nanoparticles when Exposed (NH3, NO2) Gases

This study is about gas sensor preparation of hydroxyl functionalized multiwall carbon nanotubes (MWCNTs-OH) network use filtration from suspension (FFS) method. Improve the properties of the sensor use embedded nanoparticles (PANI, Pt-CNT active, Ni). the gas sensor good responce toward Exposure (NH3, NO2) gases at room temperature and at low concentration (1ppm). The sensor was more responsive when exposure to NO2 gas because it is an oxidizing gas(corroded), When exposure NH3 gas for concentration (1ppm ) and embedded Ni NP the sensitivity value (3.41, 3.49, 9.7 and 5.4) % at the temperatures (RT, 50, 100 and 150 ) C˚. The recovery time was decreases at (150)C˚ as it was (5.4)sec , the factors to improve the properties of the sensor was increase temperature and embedded NPs.

ZIF-8-derived ZnO/C decorated hydroxyl-functionalized multi-walled carbon nanotubes as a new composite electrode for supercapacitor application

Due to the poor conductivity of metal-organic frameworks (MOFs), it is challenging to directly employ MOFs as electrode materials for supercapacitors. Herein, hydroxyl-functionalized multi-walled carbon nanotube (f-MWCNT) was used to decorate ZnO/C obtained from the prior calcination of pristine zeolitic imidazolate framework-8 (ZIF-8) and applied as electrode material for supercapacitor application. The resulting ZnO/C@f-MWCNT electrode exhibits excellent storage performance, as confirmed by the specific capacitance of 650 F/g at 1 A/g and a superior energy/power density compared to the single electrode. Additionally, the composite electrode displayed remarkable cycling stability of 70% after 5000 cycles and retained 75% of its initial capacitance at 10 A/g, demonstrating good rate cyclability. The exceptional performance of ZnO/C@f-MWCNT was attributed to the synergistic effects offered by f-MWCNT which improved its electrical conductivity and ZnO/C that provided sufficient redox-active sites and structural stability. This work may promote the design of advanced MOF-based nanocomposites for energy storage application.

Performance evaluation, enzymatic activity and microbial community of sequencing batch reactor under hydroxyl-functionalized multi-walled carbon nanotubes (MWCNTs-OH) stress

The nitrogen removal, microbial communities and enzymatic activities of sequencing batch reactors (SBRs) had been compared under long-term exposure of different hydroxyl-functionalized multi-walled carbon nanotubes (MWCNTs-OH) concentrations. Compared with 0 mg/L MWCNTs-OH, the chemical oxygen demand (COD) and nitrogen removals had no obvious change at 10 and 30 mg/L MWCNTs-OH during the whole operation process. However, the microbial oxygen uptake rate, nitrifying rate, denitrifying rate, dehydrogenase activity, nitrifying enzymatic activity and denitrifying enzymatic activity decreased with the increase of MWCNTs-OH concentration and operation time owing to the toxicity of MWCNTs-OH. The microbial reactive oxygen species production and lactate dehydrogenase release under MWCNTs-OH stress kept an ascending trend as the operation time increased, which might affect the normal microbial functions. The presence of MWCNTs-OH varied the microbial community structure of SBR. The relative abundances of Nitrosomonas, Nitrosospira, Nitrospira and denitrifying genera displayed some evident changes under MWCNTs-OH stress.

Multi-walled carbon nanotubes with different features reinforced cement pastes: A compressive and systematic approach using principal component analysis

The properties of multi-walled carbon nanotubes (MWCNTs) significantly affect cement paste properties. This study statistically analyzed the effects of MWCNT properties such as specific surface area, length, functional group content and outer diameter on cement paste properties, together with associated reasons. While MWCNTs with fewer functional groups, smaller surface area, shorter length and larger outer-diameter are successful in filling gel nano-micro pores, others were successful in filling micro-meso cracks. The acidic environment formed by carboxyl groups causes more void formation, while hydroxyl groups with water-absorbing structure have been effective in filling voids. Remarkable improvement ratios have been obtained in electrical resistivity (61.0%), splitting tensile strength (77.2%), CH content (51.0%), water absorption (15.2%), and porosity (6.2%) by using hydroxyl-functionalized multi-walled carbon nanotubes with a 30 nm outer wall-diameter, to replace 0.1% by weight of cement.

Carbon nanotubes grease with high electrical conductivity

While most commercial greases are used to prevent wear and tear in machinery, many specialized applications require electrically conductive grease. Applications include, but are not limited to, use in next generation electric vehicles (NGEVs), superb electric motor bearing protection, and electrical contact improvement. Using recently new invented methods, electrically conductive greases have been prepared. Petro-Canada N650HT oil with 7.5 wt% hydroxyl functionalized multiwall carbon nanotubes (MWNT-OH), yielded a surprising resistivity of 22.4 Ω cm, compared to the resistivity of 7880 Ω cm of an almost identical sample made with multiwall nanotube (MWNT). Another sample, 75 % Glycerol, 25 % Water, 4.5 wt% MWNT-OH, yielded the lowest resistivity of all samples measured, at 10.0 Ω cm. Hydrogen bonding is believed to be attributed to the best performing samples. The introduction of hydrogen bonding in any form into the grease increases electrical conductivity. This finding can be extended with further research to other nanomaterials with functional groups like OH, COOH, F, and NH.

Molecularly imprinted polymer solid-phase extraction for the analysis of 1,8-cineole in thyme and sagebrush distillates

Molecularly imprinted polymers (MIPs) are polymers possessing receptor cavities with selective characteristics. The molecularly imprinted polymer of 1,8-cineole on hydroxyl-functionalized multiwall carbon nanotubes was synthesized for selective extraction of 1,8-cineole in water distillates of Artemisia sieberi (sagebrush) and thyme samples. The MIP was synthesized with cineole as template, methacrylic acid as functional monomer, ethylene glycol dimethacrylate as cross-linker and benzoyl peroxide as initiator. The main parameters affecting the synthesis of MIP and also the extraction efficiency of the analyte were optimized. The limit of detection of 1,8-cineole was as low as 0.04 μg/mL, while the dynamic linear range was found to be in the range of 0.125–100 µg/mL. The relative standard deviations (RSDs%) found for samples spiked at 1 and 70 µg/mL were 1.45–4.3%, respectively. The relative recoveries of the spiked samples at the above concentration levels were 93.8–98.2%.

Effect and mechanisms of nanomaterials on interface between aggregates and cement mortars

As the weakest zone in concrete, the interfacial transition zone (ITZ) between aggregates and cement mortars has important effects on the properties of concrete. This paper aims to investigate the effects and mechanisms of nanofillers on the bond strength and interfacial microstructures between aggregates and cement mortars. A total of 8 representative types of nanofillers (namely nano-SiO2, nano-TiO2, nano-ZrO2, untreated multi-walled carbon nanotubes (MWCNTs), hydroxyl-functionalized MWCNTs, nickel-coated MWCNTs, multi-layer graphenes (MLGs), and nano boron nitride (nano-BN)) were selected to fabricate specimens with scale-up aggregate-cement mortar interface that can be characterized by the three-point bend test. The experimental results indicate that all types of nanofillers can enhance the bond strength between aggregates and cement mortars. The highest relative/absolute increases of 2.1 MPa/35.1%, 2.32 MPa/38.8% and 2.56 MPa/42.8% in interfacial bond strength are achieved by incorporating 2 wt% of nano-ZrO2, 0.3 wt% of nickel-coated MWCNTs, and 0.3 wt% of nano-BN, respectively. Scanning electron microscope observations show the presence of nanofillers can improve hydration products and increase interfacial compactness. Energy dispersive spectrometer results suggest that local content of nanofillers in the ITZ is higher than that in the bulk cement mortars. These findings indicate the nanofillers can transfer with water migration toward aggregates and enrich in ITZ, thus improving the bond strength and interfacial microstructures between aggregates and cement mortars through the nano-core effect.

Effect of the oxidation process on the molecular interaction of polyaromatic hydrocarbons (PAH) with carbon nanotubes: Adsorption kinetic and isotherm study

Agglomeration is a major setback in the use of pristine multiwall carbon nanotube for many applications. Therefore, application of hydroxyl functionalized multiwall carbon nanotubes (MWCNT-OH) for the removal of naphthalene and fluorine was investigated and compared with pristine MWCNT for the first time. FTIR, BET, TGA, SEM, and TEM were used to investigate the functional group, microstructure and morphology of MWCNT and MWCNT-OH. The BET results showed more mesoporosity for MWCNT-OH than MWCNT. Batch equilibrium adsorption data were fitted to the Langmuir, Freundlich and Temkin models, of which the Langmuir model exhibited the best fit. The correlation of Langmuir model for naphthalene adsorption on MWCNT-OH was observed to be higher (i.e. R2 = 0.9703 for MWCNT-OH and R2 = 0.5082 for MWCNT) while the correlation for adsorption of flourene is higher for MWCNT (i.e. R2 = 0.998 for MWCNT and R2 = 0.9517 for MWCNT-OH). The maximum adsorption capacity (qe) for MWCNT-OH (57.401 ng/g-356.121 ng/g for naph and 61.235 ng/g - 367.361 ng/g for fluorene) was generally higher and more stable for lower concentration ranges while it is comparable with MWCNT (48.177 ng/g - 354.00 ng/g for naph and 59.635 ng/g- 366.709 ng/g for fluorene) at higher concentration. The qe calculated (344.828 ng/g for naph and 357.143 ng/g for fluorene) using PSO was observed to be much closer to experimental qe (356.121 ng/g for naph and 367.361 ng/g for fluorine) for MWCNT-OH adsorbent than MWCNT (cal qe are 384.615 ng/g for naph and 400.000 ng/g for fluorene; exp qe 354.00 ng/g for naph and 366.709 ng/g for fluorene). The value of boundary layer thickness, is >0, this indicates the reaction process is quite complex and is not solely controlled by the intra-particle diffusion. The results of this study indicate the high potential of the developed MWCNT-OH adsorbent as an efficient and successful material for the removal of carcinogenic PAHs from the water body.

Facile Fabrication of Environmentally-Friendly Hydroxyl-Functionalized Multiwalled Carbon Nanotubes/Soy Oil-Based Polyurethane Nanocomposite Bioplastics with Enhanced Mechanical, Thermal, and Electrical Conductivity Properties.

It is challenging to prepare polyurethane bioplastics from renewable resources in a sustainable world. In this work, polyurethane nanocomposite bioplastics are fabricated by blending up to 80 wt % of soy-based polyol and petrochemical polyol with hydroxyl-functionalized multiwalled carbon nanotubes (MWCNTs-OH). The scanning electron microscope (SEM), transmission electron microscope (TEM), and Fourier transform infrared spectroscopy (FTIR) analyses reveal homogeneous dispersion of the MWCNTs-OH in the matrix, as well as interaction or reaction of MWCNTs-OH with the matrix or polymeric methylene diphenyl diisocyanate (pMDI) in forming the organic–inorganic hybrid bioplastic with a three-dimensional (3D) macromolecule network structure. Mechanical properties and electrical conductivity are remarkably enhanced with the increase of the multiwalled carbon nanotube (MWCNTs) loading. Dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA) results show that the bioplastics with MWCNTs-OH have a better thermal stability compared with the bioplastics without MWCNTs-OH. The composition of the nanocomposites, which defines the characteristics of the material and its thermal and electrical conductivity properties, can be precisely controlled by simply varying the concentration of MWCNTs-OH in the polyol mixture solution.

Comparing the effect of incorporation of various nanoparticulate on the performance and antifouling properties of polyethersulfone nanocomposite membranes

We have prepared polyethersulfone (PES) nanocomposite membranes comprising of cloisite 30B clay, SiO2, TiO2, hydroxyl-functionalized multi-walled carbon nanotubes (MWCNTs-OH), and carboxyl-functionalized multi-walled carbon nanotubes (MWCNTs-COOH). The nanoparticulate at five different concentrations were added into the polymeric dope solutions including 15 or 18 wt% of PES, N,N-dimethylacetamide (DMAc) or 1-methyl-2-pyrrolidone (NMP) as solvents, and 1 wt% of pore forming agent. These nanoparticulate may improve porosity, hydrophilicity, and open the channels up for improved water transport. Although many nanoparticulate with various properties and functionalities have been used for the same aims, the efforts have been made to choose the best nanomaterial and its loading among these five famous nanofillers for modifying PES ultrafiltration membrane. The nanocomposite membranes showed better antifouling characteristics and water permeability as compared with the pristine PES membrane because of the porosity and hydrophilicity improvements. However, further increasing nanoparticulate loading led to a possible agglomeration and diminished the water flux and fouling resistance. The effect of polymer concentration and solvent showed that membranes fabricated using 15 wt% of PES concentration possessed greater fouling resistance and water flux compared to those of fabricated using 18 wt% of PES concentration. Also, membranes fabricated using DMAc exhibited a more porous structure with considerably greater water flux as compared with those of fabricated using NMP as the solvent. Based on the results, 1 wt% of TiO2 is recommended as the best nanoparticulate for the PES ultrafiltration membrane modification since it exhibited the superlative performance with a 320% water flux enhancement, nearly 98% BSA rejection, and 130% FRR improvement.

Sprayed superamphiphilic copper foams for long term recoverable oil-water separation

Superamphiphilic copper foams were prepared by one-step spraying a water-borne solution of hydroxyl-functionalized multi-wall carbon nanotubes and melamine formaldehyde. Water or oil droplets can spread on the coating rapidly and completely in air; meanwhile, oil droplets underwater can retain quasi-spheres without any penetration all the time (superoleophobic underwater), and so the water droplets underoil can do (superhydrophobic underoil). The superamphiphilic copper foams which prewetted by water can effectively separate oil and water solely driven by gravity, showing high separation efficiency and water flux (>5000Lm−2h−1) for a series of oil-water mixtures. Furthermore, the as-prepared copper foams exhibited outstanding mechanical durability in the long-term mechanical wear process and excellent chemical stability under a series of harsh environment conditions, including strong acid and strong base. Meanwhile, The samples still retained the underwater superoleophobic property after 4 separation-water backwash cycles (>140 continuous separation repetitions) with the separation efficiency always remaining above 95%, which indicated the excellent recoverability and recyclability.

Effects of hydroxyl-functionalized multiwalled carbon nanotubes on sperm health and testes of Wistar rats.

Carbon nanotubes (CNTs) are promising candidates for various applications including biomedical purposes. Owing to their remarkable physical, mechanical, electrical and chemical properties, CNTs have become an area of intense research and industrial activity in recent years. Therefore, toxicity and risk assessment studies are becoming increasingly important. The present study was designed to assess the effects of hydroxyl-functionalized multiwalled CNTs (OH-f MWCNTs) on sperm health and testes of adult Wistar rats. Animals were treated with different doses of OH-f MWCNTs (0.4, 2.0 and 10.0 mg/kg) along with a control group receiving only vehicle. Assessments after 15 alternate intraperitoneal doses revealed dose-related adverse effects on many endpoints tested. Results of the study showed significant impairment of sperm health at 2.0 and 10.0 mg/kg. Histology of testes demonstrated degeneration of germinal epithelium and loss of germ cells in the treatment groups. The exposure resulted in increased oxidative stress in testes in a dose-dependent manner. The findings of the study demonstrate that CNTs are potentially harmful for male reproductive health.

Effect of bacteria on the transport and deposition of multi-walled carbon nanotubes in saturated porous media

The influence of bacteria on the transport and deposition behaviors of carbon nanotubes (CNTs) in quartz sand was examined in both NaCl (5 and 25 mM ionic strength) and CaCl2 (0.3 and 1.2 mM ionic strength) solutions at unadjusted pH (5.6–5.8) by direct comparison of both breakthrough curves and retained profiles in both the presence and absence of bacteria. Two types of widely utilized CNTs, i.e., carboxyl- and hydroxyl-functionalized multi-walled carbon nanotubes (MWCNT-COOH and MWCNT-OH, respectively), were employed as model CNTs and Escherichia coli was utilized as the model bacterium. The results showed that, for both types of MWCNTs under all examined conditions, the breakthrough curves were higher in the presence of bacteria, while the retained profiles were lower, indicating that the co-presence of bacteria in suspension increased the transport and decreased the deposition of MWCNTs in porous media, regardless of ionic strength or ion valence. Complementary characterizations and extra column tests demonstrated that competition by bacteria for deposition sites on the quartz sand surfaces was a major (and possibly the sole) contributor to the enhanced MWCNTs transport in porous media.

Sorption characteristics of tetrabromobisphenol A by oxidized and ethylendiamine-functionalized multi-walled carbon nanotubes

Two kinds of functional groups, carboxyl, and amidogen were attached to on multi-walled carbon nanotubes (MWCNTs) with mixed acid and ethylenediamine (EDA). Scanning electron microscopy and transmission electron microscopy characterization showed no distinguishable changes in morphology, but found defects on the walls of the modified MWCNTs, and X-ray diffraction characterization indicated that the MWCNTs still retain the graphite structure. The sorption kinetics, sorption isotherms, and thermodynamics of pristine and modified MWCNTs were also investigated. The results showed that the equilibrium sorption could be well modeled by a pseudo-second-order kinetic fit. The uptake of tetrabromobisphenol A (TBBPA) sharply decreased with increasing pH values under alkaline conditions and at higher temperatures. The sorption isotherms of TBBPA on MWCNTs were well described by Langmuir and Freundlich models. Carboxyl- and hydroxyl-functionalized MWCNTs (MWCNTs-O) have higher values of the change in the standard Gibbs free energy (ΔG°) than do the amino-functionalized MWCNTs (MWCNTs-N); this is in agreement with the phenomenon that MWCNTs-O have a slightly higher sorption capacity than MWCNTs-N. The calculated thermodynamic parameters suggest that the sorption of TBBPA onto the modified MWCNTs is a feasible, spontaneous, and exothermic process. It was also proposed that hydrophobic interactions and π–π interactions were dominant in TBBPA sorption onto MWCNTs. The three sorbents retain a high sorption capacity after five sorption and desorption cycles.

Effects of surface modification with 3‐aminopropyltriethoxysilane on structure and mechanical property of multiwalled carbon nanotube/polycarbonate composites

Hydroxyl functionalized multiwalled carbon nanotubes (H‐MWNTs) were silanized using 3‐aminopropyltriethoxysilane (APTES) in order to improve the dispersion and interfacial interaction in composites. MWNT/polycarbonate (PC) composites filled with H‐MWNTs and silanized MWNTs (S‐MWNTs) were fabricated by melt mixing and injection molding. Fourier transform infrared spectrometry (FTIR) and energy dispersion X‐ray spectroscopy (EDS) were employed to prove the presence of APTES on the surface of S‐MWNTs. In addition, thermogravimetric analysis (TGA) was used to evaluate the relative amount of introduced APTES. The microstructure and mechanical property of both composites were investigated by scanning electron microscopy (SEM), transmission electron microscope (TEM), tensile test and dynamic mechanical analysis (DMA). The SEM and TEM images showed that S‐MWNT/PC composites had better dispersion and interfacial adhesion than H‐MWNT/PC composites. A reinforcing and toughening effect on tensile behavior of composites was obtained after silane functionalization. The storage modulus of composites increased markedly as a function of MWNTs content, especially for the composites with S‐MWNTs. In summary, the silanization can improve the dispersion of MWNTs and the interfacial adhesion between MWNTs and PC so as to enhance the mechanical properties of composites. POLYM. COMPOS., 37:1914–1923, 2016. © 2015 Society of Plastics Engineers

The influence of hydroxyl-functionalized multi-walled carbon nanotubes and pH levels on the toxicity of lead to Daphnia magna

The acute toxicity of lead was examined for Daphnia magna in waters with different pH values (5.0, 6.0, 7.0, 8.0 and 9.0) and different concentrations (0.01, 0.10, 0.50 and 1.00mg/L) of hydroxyl-functionalized multi-walled carbon nanotubes (OH-MWCNTs). The results indicated that pH values could affect the toxicity of lead. With pH values increasing from 5.0 to 9.0, the 24h-LC50 of Pb(II) increased from 0.784 to 9.473mg/L, suggesting that the toxicity of Pb(II) was dramatically decreased. Although OH-MWCNTs almost caused no lethal effect to D. magna at the studied four concentrations, the combination of OH-MWCNTs and Pb(II) could cause more serious toxic effects to D. magna than Pb(II) alone. This study indicated that the synergistic effect caused by CNTs and lead could not be neglected.

Physical properties of maleated poly(lactic acid) composites containing different functionalized multiwalled carbon nanotubes.

In the current study, maleic anhydride-grafted poly(lactic acid) (MA-g-PLA) was prepared by using a reactive blending method to improve interfacial interaction and compatibilization in PLA/functionalized multiwalled carbon nanotube nanocomposites. Concentrations of maleic anhydride and initiator were varied at 3, 5 wt% and 0-0.7 wt%, respectively. The maleation content was determined by using a titration method, in which MA-g-PLA containing the optimum degree of grafting was subsequently chosen to prepare the nanocomposites containing hydroxyl and carboxylic functionalized multiwalled carbon nanotubes at various contents (0-5 wt%) and compared with the ones prepared with non-functionalized type. Dispersion morphology, thermal and mechanical properties of the resultant nanocomposites were investigated by means of transmission electron microscopy, differential scanning calorimetry, thermogravimetric analysis, and tensile measurement. It was shown that the compatibility between the nanotubes and MA-g-PLA was improved where the functionalized nanotubes exhibited a better dispersion and mechanical property than the nonfunctionalized nanotubes. With increasing concentration of carbon nanotubes, tensile strength and Young's modulus of the nanocomposites were correspondingly enhanced, in which at 5 wt% addition yielded the highest values at 90 MPa and 10 GPa, respectively.

Novel THTBN/MWNTs-OH polyurethane conducting composite thin films for applications in detection of volatile organic compounds

Novel polyurethane (PU) conducting composite thin films based on tetrahydroxyl-terminated poly(butadiene-co-acrylonitrile) (THTBN) and hydroxyl-functionalized multi-walled carbon nanotubes (MWNTs-OH), were prepared via an in-situ coupling reaction route between hydroxyl groups and isocyanate groups. The chemical and crystal structures were characterized by Fourier transform infrared spectra (FTIR) and X-ray diffraction (XRD). The morphologies and the dispersion behavior of THTBN/MWNTs-OH were examined by scanning electron microscope (SEM), transmission electron microscopy (TEM) and UV–Vis measurements. The influence of MWNTs-OH loading amount on conducting properties and response to some volatile organic compounds (VOCs) especially benzene and toluene was investigated. The experimental results indicated that MWNTs-OH was tightly encapsulated by PU moieties and homogeneously dispersed in the PU moieties. The as-prepared THTBN/MWNTs-OH PU conducting thin films exhibited strong and selective response to nonpolar benzene and toluene vapors, and the response depends on the loading of MWNTs-OH and VOC vapor concentrations. The improvement in dispersity and sensing properties were closely correlated with the chemical linkage of MWNTs-OH in the THTBN matrices through bridging molecules HDI. The developed PU conducting thin films had fast response and reversibility, significant reproducibility and long-term stability. Therefore, they had a possibility as a candidate of volatile organic solvent vapor sensors.