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In this work, aramid nanofibers (ANFs)/reduced graphene oxide (ANFs/RGO) film electrodes were prepared by vacuum-assisted filtration, followed by hydroiodic acid reduction. Compared with thermal reduced ANFs/RGO, these as-prepared film electrodes exhibit a combination of mechanical and electrochemical properties with a tensile strength of 184.5 MPa and a volumetric specific capacitance of 134.4 F/cm3 at a current density of 0.125 mA/cm2, respectively. In addition, the film electrodes also show a superior cycle life with 94.6% capacitance retention after 5000 cycles. This kind of free-standing film electrode may have huge potential for flexible energy-storage devices. [ABSTRACT FROM AUTHOR]

In this work, a distinguished hydrothermal treatment succeeded in modifying aramid nanofibers (ANFs) with the help of mixed acid, and the hydrothermal-treated ANFs (hANFs) were regarded as a reinforcement agent to be introduced into styrene-butadiene rubber (SBR) via latex co-agglutination treatment. The enhanced comprehensive behaviour of SBR/hANFs composites induced by π-π stacking interaction between hANFs and polymer chains were investigated in details. With respect to virgin SBR, it was found that the temperature at maximum rate of degradation, tear strength and tensile strength of composites with adding 7 phr (parts per hundred rubber) hANFs significantly improved by 14 °C, 148 % and 215 %, respectively. The incorporation of hANFs also endowed SBR with greatly enhanced solvent resistance. [ABSTRACT FROM AUTHOR]

Abstract: Styrene–butadiene rubber (SBR) nano‐composites were prepared through mixing SBR latex with bacterial cellulose whiskers (BCWs). BCWs were extracted from the residual bacterial cellulose (BC) that was treated with acid hydrolysis. A rod‐like nanofiber structure of BCWs was observed by transmission electron microscopy and atomic force microscopy. BCWs maintained the crystal structure in BCWs/SBR nano‐composites as confirmed by X‐ray diffraction patterns. The dispersion of BCWs in SBR matrix was further detected with field emission scan electron microscope. BCWs acted as a multifunctional physical cross‐linker in the SBR matrix, the combination of BCW reinforcement and increased effective cross‐linking density of the rubber network with incorporating BCWs would cause a more effective transfer of stresses from matrix to filler. Compared with neat SBR, the tensile strength and tear strength of SBR/BCW nano‐composite with 2.5 phr (parts per hundred rubber) BCWs were increased by 319% and 182%, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Carboxylated acrylonitrile–butadiene rubber (XNBR) and styrene–butadiene rubber (SBR) composites with 3 phr (parts per hundred rubber) graphene oxide (GO) were prepared using a latex mixing method. Effects of XNBR/SBR blend ratios on the mechanical properties, thermal conductivity, solvent resistance and thermal stability of the XNBR/SBR/GO nanocomposites were studied. The tensile strength, tear strength, thermal conductivity and solvent resistance of the XNBR/SBR/GO (75/25/3) nanocomposite were significantly increased by 86, 96, 12 and 21%, respectively, compared to those of the XNBR/SBR (75/25) blend. The thermal stability of the nanocomposite was significantly enhanced; in other words, the temperature for 5% weight loss and the temperature of the maximal rate of degradation process were increased by 26.01 and 14.97 °C, respectively. Theoretical analysis and dynamic mechanical analysis showed that the GO tended to locate in the XNBR phase, which led to better properties of the XNBR/SBR/GO (75/25/3) nanocomposite. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Ionic liquid 1-allyl-3-methyl-imidazolium chloride (AMICl) is used to fine-tune the surface properties of graphene oxide (GO) sheets for fabricating ionic liquid functionalized GO (GO-IL)/styrene-butadiene rubber (SBR) nanocomposites. The morphology and structure of GO-IL are characterized using atomic force microscope, X-ray diffraction, differential scanning calorimetry, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, UV-vis spectra and Raman spectra. The interaction between GO and AMICl molecules as well as the effects of GO-IL on the mechanical properties, thermal conductivity and solvent resistance of SBR are thoroughly studied. It is found that AMICl molecules can interact with GO via the combination of hydrogen bond and cation-π interaction. GO-IL can be well-dispersed in the SBR matrix, as confirmed by X-ray diffraction and scanning electron microscope. Therefore, the SBR nanocomposites incorporating GO-IL exhibit greatly enhanced performance. The tensile strength, tear strength, thermal conductivity and solvent resistance of GO-IL/SBR nanocomposite with 5 parts per hundred rubber GO-IL are increased by 505, 362, 34 and 31%, respectively, compared with neat SBR. This method provides a new insight into the fabrication of multifunctional GO-based rubber composites. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT The natural rubber (NR) nanocomposites were fabricated by filling ionic liquid (1-allyl-3-methyl-imidazolium chloride, AMI) modified nano-silica (nSiO2) in NR matrix through mechanical mixing and followed by a cure process. Based on the measurements of differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), solid state nuclear magnetic resonance spectroscopy, and Raman spectroscopy, it was proved that AMI could interact with nSiO2 through hydrogen bonds. With the increase of AMI content, the curing rate of nSiO2/NR increased. The results of bound rubber and dynamic mechanical properties showed that polymer-filler interaction increased with the modification of nSiO2. Morphology studies revealed that modification of nSiO2 resulted in a homogenous dispersion of nSiO2 in NR matrix. AMI modified nSiO2 could greatly enhance the tensile strength and tear strength of nSiO2/NR nanocomposites. Compared to unmodified nSiO2/NR nanocomposite, the tensile strength of AMI modified nSiO2/NR nanocomposite increased by 102%. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44478. [ABSTRACT FROM AUTHOR]

The carbon-silica dual phase filler (CSDPF) was modified by bis (3-triethoxy-silylpropyl) tetrasulphane (Si69) and 1-allyl-3-methyl-imidazolium chloride (AMI), respectively. The natural rubber (NR) vulcanizates filled with modified CSDPF were fabricated through mechanical mixing followed by a high-temperature cure process. The impacts of filler surface modification on the curing characters, crosslinked junctions, network structure, and mechanical properties of NR vulcanizates were investigated. The results showed that the Si69 interacted with CSDPF through covalent bond, while the interaction between AMI and CSDPF was hydrogen bond. Both modifications increased the cure rate of CSDPF/NR compounds as well as the crosslinked degree, compared with those of pristine CSDPF/NR compound. The modifications improved the dispersion of CSDPF in NR matrix. The covalent modification by Si69 caused a limited movement of NR chains in the CSDPF surface, which contributed to a greater tensile modulus of Si69-modified CSDPF/NR. However, the higher content of mono-sulfidic crosslink and the poorer content of strain-induced crystallization in the NR matrix led to a slight increase of tensile strength and tear strength of Si69-modified CSDPF/NR, compared with those of CSDPF/NR. The tensile modulus of AMI-modified CSDPF/NR had a lower value due to a faster polymer chain motion on the CSDPF surface. However, the tensile and tear strength of AMI-modified CSDPF/NR increased significantly because of the increase of mono-sulfidic crosslink, strain-induced crystallization, and the existed hydrogen bond between CSDPF and NR. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT This article presents a study on blends of high fluid polypropylene (HF-PP)/metallocene poly(ethylene-butane-hexene) copolymer (mEBHC) prepared by melt-blending process using a twin-screw extruder. Six different mass fractions of mEBHC in the blends: 0, 5, 10, 30%, and 100% were investigated in our study. The thermal behavior, fracture surface morphology, mechanical properties, and rheological properties of the blends were analyzed. Our results suggested that phase separation of HF-PP/mEBHC blends occurred during the cooling process. The addition of 30 wt % mEBHC resulted in a rise of crystallinity of HF-PP/mEBHC blends from 22.8% to 34.9%. The wide-angle X-ray diffraction (WAXD) showed that the incorporation of mEBHC did not have any influence on the intrinsic crystal structure of HF-PP. The droplet-matrix micrographs of the blends given by scanning electron microscope (SEM) revealed that mEBHC particles were dispersed as 'droplet' in HF-PP continuous phase. When mEBHC content was increased up to 30%, the impact strength at 23°C and −20°C of HF-PP/mEBHC blends were improved by 150 and 35%, respectively, while the tensile strength and flexural strength were decreased slightly, compared to pristine HF-PP. The apparent shear viscosities of blends were similar to that of pristine HF-PP. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2557-2562, 2013 [ABSTRACT FROM AUTHOR]

Water‐dispersible hydrolyzed Kevlar nanofibers (hANFs) prepared by acid‐assisted hydrothermal treatments of Kevlar nanofibers (ANFs) were first incorporated into carboxylated acrylonitrile butadiene rubber (XNBR) by a latex co‐coagulation method. The obtained hANFs maintained the one‐dimensional nanofibrous morphology and crystal structure as ANFs. There were amounts of polar groups appearing at the end of hANFs molecular chains after hydrothermal process, which led to the strong hydrogen bonding interaction between the filler and XNBR matrix. The results indicated that hANFs had significant reinforcement effects on the mechanical properties, crosslink density, and thermal stability of XNBR matrix. In comparison with those of neat XNBR, the tensile strength, tear strength, crosslink density, and maximum heat decomposition temperature (Tmax) of XNBR/hANFs nanocomposites filled with 7 phr hANFs increased by 236%, 161%, 35%, and 19.64 °C, respectively. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47698. Water‐dispersible hydrolyzed Kevlar nanofibers with large amounts of polar groups will have good dispersibility in carboxylated acrylonitrile butadiene rubber matrix as well as better interaction with the matrix via hydrogen bonding. [ABSTRACT FROM AUTHOR]

In this paper, graphene oxide (GO) was modified with carboxylated acrylonitrile-butadiene rubber (xNBR) to synthesize the xNBR modified GO (xNBR-GO), which was adopted to reinforce styrene-butadiene rubber (SBR) nanocomposites through latex compounding method. The interaction between GO and xNBR was verified by Fourier transform infrared spectroscopy (FTIR) and Raman spectra. The dispersion of filler and morphology of xNBR-GO/SBR nanocomposites were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The mechanical properties, dynamic mechanical properties, thermal stability, thermal conductivity as well as solvent resistance of the xNBR-GO/SBR nanocomposites were also thoroughly studied. It was confirmed that xNBR could interact with GO through hydrogen bonding. The modification would improve the dispersion and reinforcement of filler. With the incorporation of 5 phr (parts per hundred rubber) filler, the tensile strength, tear strength and thermal conductivity of xNBR-GO/SBR nanocomposite were increased by 545%, 351% and 31.7%, respectively. In addition, the equilibrium solvent uptake was decreased by 31.8%, and the thermal stability was enhanced. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) with various oxidation degrees were prepared through a modified Hummer’s method by varying the dosage of oxidizing agent. Styrene-butadiene rubber (SBR)/carboxylated acrylonitrile butadiene rubber (XNBR)/GO nanocomposites were fabricated by aqueous-phase mixing of GO colloidal dispersion with SBR latex and a small loading of XNBR latex, followed by co-coagulation. Effects of GO oxidation degree on the morphology, structure, mechanical and thermal properties of nanocomposites were thoroughly investigated. The results showed that the mechanical strength of nanocomposites were enhanced with the increase of oxidation degree of GO. Especially, when the weight ratio of KMnO 4 to graphite was 15/5, the tensile strength, tear strength and thermal conductivity of SBR/XNBR/GO filled with 3 phr (parts per hundred rubber) GO increased by 255.3%, 141.5% and 22.8%, respectively, compared to those of neat SBR/XNBR blend. In addition, the thermal stability and the solvent resistance of the nanocomposites were also improved significantly. This work suggested that GO with higher oxidation degree could effectively improve the properties of SBR/XNBR blend. [ABSTRACT FROM AUTHOR]

In this paper, graphene oxide (GO) with different oxidation degrees were prepared by a modified Hummers' method, and were filled into carboxylated acrylonitrile butadiene rubber (XNBR) by latex co-coagulation method. The impact of oxidation degrees on the structure of GO, the interaction between GO and XNBR, the mechanical properties and thermal conductivity of XNBR nanocomposites were investigated. The results indicated that interfacial interaction between XNBR and GO became stronger with the increase of oxidation degrees of GO due to more oxygen-containing groups forming on the GO sheets and hydrogen bonding in the XNBR/GO nanocomposites, which led to a better dispersion of GO in rubber matrix as well as improved mechanical properties and thermal conductivity of XNBR matrix. Especially, in comparison with those of neat XNBR, the tensile strength, tear strength and thermal conductivity of XNBR/GO nanocomposites with 4 phr (parts per hundred rubber) GO3 increased by 114.6%, 88.5% and 27.2%, respectively. [ABSTRACT FROM AUTHOR]

Abstract In this work, a facile and effective approach is developed to obtain the water-dispersible Kevlar nanofibers (KNFs) by modifying KNFs with the assistance of epichlorohydrin (ECH). And the ECH-modified KNFs (m-KNFs) are firstly utilized to prepare styrene–butadiene rubber (SBR)/m-KNFs nanocomposites through latex co-coagulation method. The multifunctional properties of SBR/m-KNFs nanocomposites are thoroughly investigated. It is confirmed that m-KNFs have strong interactions with SBR via π-π stacking, which can generate huge enhancement on the performance of SBR nanocomposites. For example, the tensile strength, tear strength and the maximum decomposition temperature of SBR filled with 7 phr (parts per hundred rubber) m-KNFs are increased by 576%, 202% and 13.1 °C, respectively, compared with those of neat SBR. Meanwhile, the presence of m-KNFs has also improved the dielectric constant of SBR nanocomposites. This work provides a new insight into the fabrication of multifunctional KNFs-based rubber composites. [ABSTRACT FROM AUTHOR]

This work reports a novel compatibilizer and reinforcing filler, graphene oxide (GO), which significantly improved the thermal and mechanical properties of immiscible carboxylated acrylonitrile butadiene rubber (XNBR) and styrene butadiene rubber (SBR) blends. The observed glass transition temperature shift of XNBR/SBR blends demonstrated the improved compatibility of XNBR and SBR. The analysis by Fourier transform infrared spectra and Raman spectroscopy indicated that GO could form both hydrogen bonding with XNBR and π - π conjugation with SBR, which favored the compatibility of XNBR and SBR components in the blends. This unique amphiphilic character of GO enabled it interact with both polar and non-polar components and significantly improve the mechanical properties of the system. With incorporation of only 0.3 phr (parts per hundred rubber) GO, the tensile strength and tear strength of XNBR/SBR blend increased by 71% and 94%, respectively. The temperature of the maximal rate of degradation process improved by 10 °C, and a higher resistance to swelling in toluene was obtained as well. This work suggests the GO has the potential to be a suitable reinforcing filler and compatibilizer in the immiscible XNBR/SBR blends. [ABSTRACT FROM AUTHOR]

In this work, water-dispersible modified Kevlar nanofibers (m-KNFs) were successfully prepared through grafting Kevlar nanofibers (KNFs) with epichlorohydrin (ECH). Then m-KNFs were incorporated into the compound of carboxylated acrylonitrile butadiene rubber (XNBR)/styrene butadiene rubber (SBR) thanked to a facile latex co-coagulation method. The interactions among m-KNFs, XNBR and SBR as well as the compatibility and mechanical properties of XNBR/SBR/m-KNFs blends were investigated. The dynamic mechanical analysis and differential scanning calorimetry analysis showed that the glass transition temperature (T g) shifted mutually between XNBR and SBR confirming enhanced compatibility between XNBR and SBR. Moreover, Fourier transform infrared spectra demonstrated that m-KNFs might form covalent bonding with XNBR, while Raman spectra indicated that m-KNFs were ability to interact with the aromatic structure of SBR via π - π conjugation, which was responsible for the improved mechanical behaviors and compatibility of blends. With the addition of only 0.3 phr (parts per hundred rubber) m-KNFs, the tensile strength and tear strength of XNBR/SBR/m-KNFs blend were improved by 87.2% and 194.7%, respectively, compared with those of neat XNBR/SBR blend. Image 1 • The water-dispersible aramid nanofibers were successfully modified. • The compatibility of rubber blends was improved. • The mechanical properties of rubber blends were enhanced. • The modified aramid nanofibers could enhance and compatibilize immiscible rubber blends. [ABSTRACT FROM AUTHOR]