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In the present study, attempts were made to manufacture innovative conducting polymer nanocomposites (CPCs) with high performance, low cost, and appropriate electrical, mechanical, and thermal properties. However, one of the main challenges in creating CPCs is the tendency of nanofillers to agglomerate and accumulate, resulting in a decrease in the electrical properties and performance of CPCs. To address this issue, the study developed an efficient and eco‐friendly CPC using carboxymethyl cellulose (CMC) as a binder and carbon nanotubes (CNTs) and graphene nanoplatelets (GNPs) as nanofillers. The study employed a chemical functionalization method to modify CNTs and enhance their compatibility and dispersion properties in the CMC matrix. The prepared CPCs were characterized using various techniques, including Fourier‐transform infrared spectroscopy, x‐ray diffraction, and field emission scanning electron microscopy. The results showed an improvement in homogeneity and surface cohesion between CMC and O‐CNTs through chemical surface modification of CNTs via carboxylic acid functional groups. The study observed good dispersion of nanofillers without any aggregation of the CMC/GNP/O‐CNT compared with the nontreated CMC/GNP/CNT composite. While a decrease in the degree of crystallinity was observed, conductivity increased for the CPC containing oxidized CNTs. The study found that the highest conductivity of ~112 S/m was obtained for D‐CMC/GNP/O‐CNT with 25 wt% of O‐CNT, while the maximum conductivity of D‐CMC/GNP/CNT was ~80 S/m with 35 wt% of CNTs. Additionally, the study observed an improvement in electrochemical properties after treatment of CNTs in the form of higher cathodic current in cyclic voltammetry and lower charge transfer resistance in impedance spectroscopy of D‐CMC/GNP/O‐CNT35 compared to untreated one. Highlights: Preparation of new conductive nanocomposite consisting of CMC, CNTs, and GNPs.Carboxylation of CNTs to improve O‐CNT and CMC intermolecular interactionCMC/GNP/O‐CNT is 40% more conductive than unmodified CNT nanocomposite.Higher thermal stability and mechanical properties were observed by using O‐CNT.O‐CNT caused higher current density and lower electron transfer resistance for CPCs. [ABSTRACT FROM AUTHOR]

Different contents of functionalized graphene nanoplatelet (FGNP) were incorporated into the blend of poly (lactic acid)/chitosan (PLA/CS) (75/25 wt/wt), and the effect of nanoplatelet addition on mechanical properties, biodegradability behavior, and electrical conductivity of the blend was investigated. The results revealed the proper dispersion of FGNP in the blend, and the nanocomposite containing 3 phr FGNP (PLA75/CS25/FGNP3) demonstrated the finest morphology and the narrowest size distribution. The nanocomposite filled with 3 phr FGNP indicated an improvement of approximately 142% and 261% in tensile strength and Young's modulus, respectively, compared to the neat blend. Moreover, with the addition of 3 phr FGNP to the PLA/CS blend, thermal stability significantly improved. In addition, the study of biodegradability behavior demonstrated that the weight loss rate enhanced over time. From the fifth week onwards, the weight loss rate diminished because of the decrease in the number of degradable functional groups in the nanocomposite. On the other hand, the thermal conductivity of PLA75/CS25/FGNP3 showed an improvement of higher than 12 orders of magnitude compared to the neat blend. In addition, experimental data on electrical conductivity and power‐law model predictions were consistent. [ABSTRACT FROM AUTHOR]

The principles of large deformation rubber viscoelasticity are not new, but there is a need to make explicit certain theories or modify the available models for deeper understanding of behavior of rubber nanocomposites. The difficulties are chiefly due to the assumptions under which a given theoretical model fails to predict large deformation behavior of elastomer nanocomposites, as models are basically proposed for neat rubbers, and more critically they can hardly be supposed to remain valid for systems in which two or more nanofillers having different nature, shape, and size are used. This work attempts to apply nonlinear hyperelastic theoretical models proposed for hyperelastic behavior of rubbers for nanocomposites containing multi‐walled carbon nanotubes (MWCNTs) and graphene nanoplatelets (GnPs), and to explore the interplay between morphology, viscoelastic properties, and large deformation behavior of typical hydrogenated acrylonitrile butadiene rubber (HNBR)‐based rubber nanocomposites. Morphological observations used for knowing the localization of nanofillers, where dynamic mechanical and uniaxial tensile strength analyses exhibited a rise in both Young's modulus and tensile strength of composites by MWCNTs and GNPs content up to 200 and 160%, respectively. We applied Arruda‐Boyce model and appropriately predicted nonlinear hyperelastic behavior of HNBR model nanocomposites and interfacial interactions between phases, as recognized by comparing model parameters for nanocomposites containing only MWCNTs, or only GNPs, and their combinations varying filler content. POLYM. COMPOS., 40:E1548–E1558, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Thermo‐mechanical and shape memory behavior of melt processed TPU/ABS (80/20 w/w) blends compatibilized with varying amounts of ABS‐g‐MAH loaded with multiwalled carbon nanotubes (MWCNTs) were discussed. The morphological observations by SEM and TEM techniques confirmed that introduction of ABS‐g‐MAH leads to a significant reduction in the size of ABS domain size due to improvement of interfacial adhesion between the blend components. Incorporation of MWCNTs to the compatibilized blend resulted in further reduction of the ABS droplet size. Mechanical properties investigations revealed that tensile strength of the TPU/ABS blend being about 26.4 MPa increases to 44.6 MPa, that is, about 70% improvement, on incorporation of 6 wt% ABS‐g‐MAH to the noncompatibilized blend. In the same direction, Young's modulus increases ca. 13%. A significant enhancement of about 70% in Young's modulus of the compatibilized blend was observed by inclusion of 2 wt% MWNCNTs. The shape memory results showed that interfacial compatibilization process has a strong positive impact on the shape recovery and shape fixity ratio of the blends. Moreover, loading MWCNTs into the compatibilized blend further improved these features. POLYM. COMPOS., 40:789–800, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

As a worldwide challenge, the oil spillage has gained tremendous attention within the last few years. In this work, a facile method is proposed to fabricate sponges treated with polydimethylsiloxane (PDMS) and modified/unmodified silica nanoparticles exhibiting superhydrophobic and superoleophilic properties for enhanced oil/water separation. The main aim is to delineate the role of surface composition versus surface morphology by employing different formulations. Scanning electron microscopy results demonstrated that a rough structure, induced by formation of a packed assembly of nanoparticles, gives a major contribution to the obtained superhydrophobic behavior. It was also proved that the surface modification of silica nanoparticles might play an even more important role in attaining superhydrophobicity. Once a combination of PDMS and modified silica was used, different oil/water mixtures were efficiently separated. On the other hand, surface composition of the coating was found to be the major factor affecting wettability of sponges and their capability to separate water/oil mixtures. Therefore, results of this study can be used as a hint for designing more efficient sponge‐based systems modified with polymer nanocomposites for oil/water separation applications. POLYM. COMPOS., 40:E431–E439, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Superhydrophobic behavior was imparted on the surface of poly(methyl methacrylate) (PMMA) films using a hybrid of nanoparticles including polyhedral oligomeric silsesquioxane (POSS) and silica. To this end, an improved phase separation method based on the concurrent use of nonsolvent and nanoparticles was used. In the absence of nanoparticles, scanning electron microscopy (SEM) results revealed the surface segregation of PMMA macromolecules as the ethanol content was increased causing the roughness to be enhanced; however, no superhydrophobic property was attained. SEM and X‐ray photoelectron spectroscopy results demonstrated that POSS particles were be mainly localized at the bulk of the nanocomposite films, and thus, superhydrophobicity could not be achieved. Accordingly, hydrophobic silica nanoparticles were introduced to the formulation leading to the superhydrophobic behavior. The durability of the superhydrophobic samples was investigated by immersing the films into the solutions with different pH values under dynamic conditions. Despite its more initial hydrophobicity, the sample made via the concurrent use of nonsolvent and nanohybrid exhibited a poorer durability, which was attributed to the more porous structure and formation of large cracks at the surface layer of the films. The results of this study could be used as a hint of nanohybrids' efficiency in the fabrication of stable superhydrophobic surfaces. POLYM. COMPOS., 40:E127–E135, 2019. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Fast cure epoxy/amine‐functionalized graphene oxide (GO) nanocomposites were designed, prepared, and characterized in this work. The GO nanosheets were functionalized by aliphatic amines having the same structure but different chain length. XPS and FTIR analyses were used to probe chemical structure and elemental surface composition of nanosheets before and after functionalization. Cure kinetics analysis was performed by dynamic differential scanning calorimetry (DSC) on samples containing pristine and functionalized GO to achieve minimum possible hindered cure. Kinetic studies confirmed that addition of pristine GO brings a steric hindrance effect, as signaled by a fall in the onset temperature, exotherm temperature and the total heat of curing reaction. According to isoconversional model, activation energy of cure reaction fell from approximately 80 to slightly over 60 kJ mol−1 as a result of improved dispersion. SEM micrographs provided evidence for good dispersion of GO platelets bearing short‐arm amines; but activation energy in such system was surprisingly higher than that of the one filled with pristine GO. By contrast, network formation in nanocomposites with GO functionalized by long‐arm amine has been facilitated, signifying the dominance of aliphatic amine length over dispersion state. The accelerated/decelerated cure is inferred based on the reactivity of reaction moieties, dispersion state of GO in the epoxy matrix, and cure behavior/kinetics of nanocomposites. The developed fast cure epoxy/GO nanocomposites compete in crosslinking with blank epoxy system. POLYM. COMPOS., 39:E2016–E2027, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Quasi‐solid‐state electrolytes were prepared by employing electrospun mats based on a blend of poly (ethylene oxide) [PEO]/poly (acrylonitrile) [PAN]/graphene nanocomposites. The effects of dispersion of graphene oxide (GO) and graphene sheets (GS) on the morphology, structure, miscibility, thermal, and mechanical properties of the PEO/PAN fibrous mats were investigated. The resultant porous membranes are good absorbent of the liquid electrolyte and exhibit high ionic conductivity. Fourier transform infrared (FTIR) spectra, dynamic mechanical analysis (DMTA), and transmission electron microscopy (TEM), revealed a phase separated structure for all the samples. Furthermore, the theoretical prediction of the position of nanofillers showed that GO particles selectively located in the PEO phase, whereas GS had a tendency to place at the interface of the two phases. Results of wide‐angle x‐ray scattering (WAXS) and differential scanning calorimetry (DSC) experiments indicated that GS‐loaded sample presents lower amount of crystallinity than PEO/PAN and PEO/PAN/GO. Apart from more amorphous nature, GS‐containing mat showed more electrical conductivity which resulted in higher ionic conductivity as compared to the other samples. On the other hand, according to TEM and XRD results, uniformly distribution and exfoliation of GO nanosheets into PEO/PAN, led to a profound improvement of the mechanical properties in comparison with PEO/PAN/GS. POLYM. COMPOS., 39:3626–3635, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Some shape‐memory materials were prepared based on TPU/ABS blends containing pristine and organo‐modified multiwalled carbon nanotubes (MWCNTs). The shape memory and mechanical properties of the samples were investigated. Scanning electron microscopy (SEM) analysis performed on the morphological features of the developed samples showed the presence of pristine MWCNTs and decreased diameter of ABS droplets which were uniformly distributed within TPU matrix. Unexpectedly, the ABS droplets in nanocomposites with organo‐modified MWCNTs were greater than ABS droplets in TPU/ABS/CNT nanocomposites. These differences were attributed to different degrees in interfacial interactions between the modified MWCNT and TPU matrix. The presence of modified MWCNT in TPU matrix could have increased the differences in surface energy and polarity of TPU and ABS and it has disturbed the compatibility of the blend fundamentally. Also, the mechanical and Izod impact properties of the shape memory samples containing pristine MWCNT are better than those samples containing MWCNT‐OH and MWCNT‐COOH. The results showed optimum tensile strength in all samples containing 2 wt% MWCNTs. The shape memory results showed that the shape recovery and fixity of TPU/ABS blend improved significantly with increases in MWCNTs. The pristine MWCNTs improved the shape recovery ratio from 93.88% for the neat TPU/ABS blend to 99.3% for TPU/ABS nanocomposite by just loading MWCNTs at 2 wt%. Surprisingly, the shape fixity changed from 92.98% for the neat blend to 100% by loading of 2 wt% of MWCNT‐OH and 1 wt% of MWCNT‐COOH. The results showed that the functionalized MWCNTs had better performance in shape fixity as compared to its pristine MWCNT counterpart. POLYM. COMPOS., 39:E984–E995, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]