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Graphene oxide exhibits great applications in the rubber industry due to its unique two-dimensional nanosheet structure, significant specific surface area, good barrier property, and high reactivity. However, different rubbers, such as carboxylated nitrile butadiene rubber, natural rubber, and styrene butadiene rubber, have different interactions with graphene oxide, which have a great influence on the reinforcement effect of graphene oxide on the rubber matrix. In this work, the enhancement mechanism of graphene oxide on carboxylated nitrile butadiene rubber, natural rubber, and styrene butadiene rubber was studied and the relationship between the microstructures and properties of GO/rubber nanocomposites was investigated by combining experiments with molecular dynamics simulation. The simulation results showed that graphene oxide had the best compatibility and the strongest interaction with carboxylated nitrile butadiene rubber, resulting in the largest binding energy and the smallest fractional free volume, mean square displacement, and the change of adhesive energy. The solvent resistance and mechanical properties of carboxylated nitrile butadiene rubber were improved by introducing graphene oxide, which was consistent with simulation results. This study provides a new way to explore the macroscopic properties of rubber nanocomposites at the molecular level. [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]

In this work, graphene oxide (GO) with various oxidation degrees were synthesized by adjusting the dosage of oxidation agent based on a modified Hummers' method, and were then used for the fabrication of the styrene–butadiene rubber (SBR)/GO nanocomposites through latex coagulation method, followed by a high‐temperature cure process. The vulcanization characteristics, thermal stability, mechanical properties, thermal conductivity as well as solvent resistance of SBR/GO nanocomposites were investigated. The results indicated that various surface structures of GO due to oxidation degrees may lead to different dispersion states of GO in the rubber matrix, and thus greatly influenced the cure rate, mechanical properties as well as thermal conductivity of SBR/GO nanocomposites. The optimal (moderate) oxidation degree of GO was achieved at the oxidation agent (KMnO4)/graphite weight ratio 9/5, for which case the tensile strength, tear strength, and thermal conductivity of SBR/GO nanocomposites increased by 271.3%, 112.3%, and 28.6%, respectively, compared with those of neat SBR. In addition, the mentioned nanocomposites also showed the best solvent resistance in toluene. POLYM. ENG. SCI., 58:1409–1418, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Water‐induced mechanically adaptive rubber nanocomposites were prepared by mixing bacterial cellulose whiskers (BCWs) suspension with styrene‐butadiene rubber (SBR) latex, followed by evaporation method. The structure, morphology, dynamic mechanical properties, water stimuli‐responsive behavior, and biodegradability of SBR/BCWs nanocomposite films were investigated. The results showed that the hydrophilic whiskers had a significant reinforcement effect on the storage modulus of SBR matrix, which originated from the formation of a rigid three‐dimensional filler network within matrix by strong hydrogen bonding between whiskers. The SBR/BCWs nanocomposites showed pronounced water stimuli‐responsive behavior compared with neat SBR. The storage modulus of SBR/BCWs nanocomposite could be decreased by 99.2% after equilibrium water swelling. This remarkable water‐triggered modulus change is attributed to the disentanglement of BCWs network via competitive hydrogen bonding with water. [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]

A facile non-covalent surface treatment method is reported in this paper to modify graphene oxide (GO) sheets with the assistance of polyvinylpyrrolidone (PVP). The PVP-modified GO (PGO) was further adopted to fabricate PGO/styrene-butadiene rubber (SBR) nano-composites through the latex compounding method. The properties of PGO were carefully investigated and interaction between GO and PVP molecules was confirmed. The mechanical properties, dynamic mechanical properties, thermal stability, thermal conductivity as well as swelling properties of the PGO/SBR nano-composites were thoroughly studied. It was confirmed that PVP molecules could have strong interaction with GO via hydrogen bond; thus, the PGO significantly improved the strength of SBR matrix, e.g., 517 and 387 % increase in tensile strength and tear strength, respectively, with the presence of only 5 phr (parts per hundred rubber) PGO in the nano-composite. The presence of PGO had also greatly reduced the glass transition temperature ( T) and enhanced the storage modulus of SBR matrix in the nano-composites. Meanwhile, the maximum heat decomposition temperature ( T) was increased by 23.6 °C; equilibrium solvent uptake in toluene was reduced by 41 % and thermal conductivity was increased by 30 %. All the observations indicated that PVP modification of GO can achieve excellent exfoliation and dispersion of GO in the SBR matrix. These findings were further supported by X-ray diffraction and scanning electron microscopy measurements. [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]

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]

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]