Synthesis of polyaniline/montmorillonite nanocomposites with an enhanced anticorrosive performance

Polyaniline/montmorillonite (PANI/Mt) nanocomposites (1–7% (w/w) Mt based on the aniline content) were synthesized by in situ chemical oxidative polymerization with a 73.4–75.8% monomer conversion level. Fourier-transform infrared and scanning electron microscopy analyses confirmed the presence of Mt incorporation into PANI, whilst X-ray diffraction analysis revealed the exfoliated structure and that PANI was intercalated between the Mt layers. Thermogravimetric analysis revealed that the thermal properties of PANI and PANI/Mt composites were enhanced with increasing Mt levels.     

Green Process for Natural Rubber Latex Hydrogenation via Metathesis

Natural rubber (NR) is an important renewable polymeric material which contains cis-1,4-polyisoprene as a major component. A new approach for a green hydrogenation process has been developed in this research work. This metathesis/hydrogenation method has less detrimental environmental impact and provides improved thermal stability of NR.     

Polyisoprene modified poly(alkyl acrylate) foam as oil sorbent material

Biorenewable polyisoprene latex obtained from natural rubber, Hevea brasiliensis, was used to prepare the reusable polyisoprene–poly(alkyl acrylate) foam for petroleum‐based liquid absorption. The foam was produced via latex vulcanization and cured by steaming. The effect of various types of poly(alkyl acrylate) such as poly(methyl methacrylate) (PMMA), poly(butyl methacrylate) (PBMA), and poly(butyl acrylate) (PBA) on oil sorption capacity of the foam were studied. Scanning electron microscope (SEM) images showed interconnected open‐cell macrostructure with the foam porosity greater than 75% and good compression set. The oil sorption capacity of the foam was in the range of 2.0–16.6 g g^?1. The addition of poly(alkyl acrylate) enhanced hydrophobicity and oil sorption capacity of the foam. The absorbed oil was easily recovered by squeezing and the foam can be reused up to 30 sorption–desorption cycles and still preserve high quality sorption. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42688.     

One‐step latex compounding method for producing composites of natural rubber/epoxidized natural rubber/aminosilane‐functionalized montmorillonite: enhancement of tensile strength and oil resistance

Montmorillonite (Mt) was intercalated with cetyltrimethylammonium bromide and functionalized with three types of aminosilane (3‐aminopropyltrimethoxysilane, n‐(2‐aminoethyl)‐3‐aminopropyltrimethoxysilane and 3‐[2‐(2‐aminoethylamino)ethylamino]propyltrimethoxysilane). The modified Mt was compounded with natural rubber (NR)/epoxidized natural rubber (ENR) via one‐step latex compounding. The effect of the modified Mt content on the oil resistance and mechanical properties of the NR/ENR/modified Mt composites was investigated. The X‐ray diffraction patterns of the composites showed partial intercalation/exfoliation of the modified Mt in the rubber matrix. Cryogenic fracture and X‐ray fluorescence results revealed highly dispersed modified Mt in the composites in the presence of 10 phr ENR. All three aminosilane groups slightly improved the oil resistance, with the long‐alkyl‐length group producing the greatest improvement. The addition of a small amount of modified Mt improved both oil resistance and tensile strength by increasing in the average diffusion path length in the NR matrix and enhancing the interaction between the modified Mt and the epoxide groups in ENR. The addition of 1.0 phr of modified Mt increased the tensile strength by 18% and decreased the elongation at break by 12% compared with a neat NR/ENR blend. © 2017 Society of Chemical Industry     

Large electrostrain in low-temperature sintered NBT-BT-0.025FN incipient piezoceramics

It is well-known that the high sintering temperatures of (Na_1/2Bi_1/2)TiO₃ (NBT)-based incipient piezoceramics limit their applications on low-cost multilayer piezoelectric actuators with base metal internal electrodes. In this work, a synergistic sintering additive of 0.75 wt% Li₂CO₃ and 0.75 wt% CuO was utilized to explore the effect on sintering behavior and electrostrain of (Na_1/2Bi_1/2)_0.935Ba_0.065Ti_0.975(Fe_1/2Nb_1/2)_0.025O₃ (NBT-BT-0.025FN) incipient piezoceramic. The optimal sintering temperature of NBT-BT-0.025FN decreased from 1160°C to 940°C due to the formation of a liquid phase, with limited degradation on electrostrain. When sintered at 940°C, a large strain of 0.39% (a nominal piezocoefficient of 571 pm/V) was achieved, which is promising for potential actuator applications co-firing with Ag electrodes.     

High Catalytic Activity of a Nickel Phosphide Nanocatalyst Supported on Melamine-Doped Activated Carbon for Deoxygenation

Topics in Catalysis - Nickel-based catalysts are inexpensive and exhibit high catalytic activity; therefore, they have been extensively explored in deoxygenation reactions. Employing catalyst...