Supplier selection plays an important role in the supply chain management and traditional criteria such as price, quality, and flexibility are considered for supplier performance evaluation in researches. In recent years sustainability has received more attention in the supply chain management literature with triple bottom line (TBL) describing the sustainability in supply chain management with social, environmental, and economic initiatives. This paper explores sustainability in supply chain management and examines the problem of identifying a new model for supplier selection based on extended model of TBL approach in supply chain by presenting fuzzy multicriteria method. Linguistic values of experts' subjective preferences are expressed with fuzzy numbers and Neofuzzy TOPSIS is proposed for finding the best solution of supplier selection problem. Numerical results show that the proposed model is efficient for integrating sustainability in supplier selection problem. The importance of using complimentary aspects of sustainability and Neofuzzy TOPSIS concept in sustainable supplier selection process is shown with sensitivity analysis.

A new conducting copolymer, polyacrylonitrile-graft-polyaniline (PAN-g-PANi), has been prepared by chemical and electrochemical methods from a precursor polymer. Poly[acrylonitrile-co-(acrylimine phenylenediamine)] (PAN-co-PAIPD) was synthesized chemically by reacting PAN with sodium 1,4phenylenediamine salt. PAN-g-PANi was synthesized chemically using ammonium peroxydisulfate as the oxidant and p-toluenesulfonic acid in dimethylsulfoxide solution and adding aniline to oxidized PAN-co-PAIPD. Electrochemical polymerization was carried out by spin coating PAN-co-PAIPD on the surface of a Pt electrode, then the growth of the graft copolymer (PAN-g-PANi) in the presence of fresh aniline and acidic solution. The structures of the graft copolymer and PAN-co-PAIPD were characterized using UV-visible, Fourier transform infrared, and 1 H and 13 C NMR spectroscopies. The thermal properties of PAN-g-PANi were studied using thermogravimetric analysis and differential scanning calorimetry. Scanning electron microscopy (SEM) images showed that the morphology of PAN-g-PANi copolymer films was homogeneous. Electrical conductivity of the copolymer was studied using the four-probe method, which gave a conductivity of 4.5 × 10 −3 S cm −1 with 51.4% PANi. SEM and electrical conductivity measurements supported the formation of the graft copolymer.

The nitration of low molecular weight polybutadiene (PB) by a convenient and inexpensive procedure was investigated. To retain the unique physico‐chemical properties of the plasticizer, it was nitrated to an extent of 10 % double bonds. The product nitropolybutadiene (NPB) was characterized by FT‐IR and 1H NMR spectroscopy as well as GPC, DSC, and TGA methods. The kinetic parameters for the decomposition of NPB from room temperature to 400 °C were obtained from non‐isothermal DSC. The changes in glass transition temperature (Tg) and inert uncured binder systems were used for determination of its efficiency as plasticizer. NPB was used in cured and unfilled nitro‐hydroxyl terminated polybutadiene (NHTPB) binder. Isothermal thermogravimetric analysis (Iso‐TGA) was employed to determine the migration rate in cured and unfilled HTPB binder systems compared to the dioctyladiphate (DOA) plasticizer. It was found that the exudation of the NPB plasticizer is slower than that of the DOA plasticizer. Thus, the NHTPB/NPB binder system (binder/plasticizer) presents more convenient mechanical properties than HTPB/DOA and is a promising new energetic binder system for polymer bonded explosives.

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In this paper, we report on the preparation of S, N co-doped carbon quantum dots (CQDs)/TiO 2 nanocomposite using a hydrothermal process where S, N-CQDs were concurrently synthesized and anchored to the surface of the TiO 2 . The prepared nanocomposite was carefully characterized to identify the morphology and structure, crystallinity, chemical composition and optical properties. The photocatalytic activity of the nanocomposite was investigated for degradation of acid red 88 (AR88) under visible light irradiation. The capability of the S, N-CQDs/TiO 2 nanocomposite to remove AR88 (77.29%) was higher than that of pure TiO 2 (23.7%). In order to determine the influencing factors on the photocatalytic activity of the prepared nanocomposite, we studied various contents of the photocatalyst, the effect of pH and the content of H 2 O 2. Further investigations were conducted to reveal the mechanism of photocatalytic degradation using radical scavenging agents. The stability and reusability of the S, N-CQDs/TiO 2 photocatalyst was tested in four reaction cycles (870 min) which showed a 25% loss of photoactivity after the fourth photocatalytic reaction.