bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spontaneous Reduction of a Hydroborane To Generate a B−B Single Bond by the Use of a Lewis Pair
Authors: Rochette Étienne , Bouchard Nicolas , Légaré Lavergne Julien , Matta Chérif F. , Fontaine Frédéric‐Georges 
Published: September 2016

AbstractThe ansa‐aminohydroborane 1‐NMe2‐2‐(BH2)C6H4 crystallizes in an unprecedented type of dimer containing a B−H bond activated by one FLP moiety. Upon mild heating and without the use of any catalyst, this molecule liberates one equivalent of hydrogen to generate a diborane molecule. The synthesis and structural characterization of these new compounds, as well as the kinetic monitoring of the reaction and the DFT investigation of its mechanism, are reported.
Cobalt‐Doped FeS2 Nanospheres with Complete Solid Solubility as a High‐Performance Anode Material for Sodium‐Ion Batteries
Authors: Zhang Kai , Park Mihui , Zhou Limin , Lee Gi‐Hyeok , Shin Jeongyim , Hu Zhe , Chou Shu‐Lei , Chen Jun , Kang Yong‐Mook 
Published: September 2016

AbstractConsidering that the high capacity, long‐term cycle life, and high‐rate capability of anode materials for sodium‐ion batteries (SIBs) is a bottleneck currently, a series of Co‐doped FeS2 solid solutions with different Co contents were prepared by a facile solvothermal method, and for the first time their Na‐storage properties were investigated. The optimized Co0.5Fe0.5S2 (Fe0.5) has discharge capacities of 0.220 Ah g−1 after 5000 cycles at 2 A g−1 and 0.172 Ah g−1 even at 20 A g−1 with compatible ether‐based electrolyte in a voltage window of 0.8–2.9 V. The Fe0.5 sample transforms to layered NaxCo0.5Fe0.5S2 by initial activation, and the layered structure is maintained during following cycles. The redox reactions of NaxCo0.5Fe0.5S2 are dominated by pseudocapacitive behavior, leading to fast Na+ insertion/extraction and durable cycle life. A Na3V2(PO4)3/Fe0.5 full cell was assembled, delivering an initial capacity of 0.340 Ah g−1.
Spontaneous Reduction of a Hydroborane To Generate a B−B Single Bond by the Use of a Lewis Pair
Authors: Rochette Étienne , Bouchard Nicolas , Légaré Lavergne Julien , Matta Chérif F. , Fontaine Frédéric‐Georges 
Published: September 2016

AbstractThe ansa‐aminohydroborane 1‐NMe2‐2‐(BH2)C6H4crystallizes in an unprecedented type of dimer containing a B−H bond activated by one FLP moiety. Upon mild heating and without the use of any catalyst, this molecule liberates one equivalent of hydrogen to generate a diborane molecule. The synthesis and structural characterization of these new compounds, as well as the kinetic monitoring of the reaction and the DFT investigation of its mechanism, are reported.
Formation damage in chemical enhanced oil recovery processes
Authors: Sheng James J. 
Published: September 2016

AbstractGenerally, we do not link enhanced oil recovery (EOR) to formation damage. However, formation damage can occur during chemical EOR processes, although it is not often discussed in literature on the topic. This unfortunate gap in EOR literature ignores the fascinating fact that sometimes the formation damages in some chemical EOR processes are the very mechanisms that enhance oil recovery. This paper summarizes all of the formation damages in chemical EOR processes. The conditions and mechanisms to occur are detailed. Benefits and consequences are discussed. Solutions to promote the benefits and negate the consequences are summarized and/or proposed. This paper suggests that relevant experiments should be conducted to assess possible formation damages in chemical EOR processes. © 2016 Curtin University of Technology and John Wiley & Sons, Ltd.
Flame‐retardant, glass‐fabric‐reinforced epoxy resin laminates fabricated through a gradient distribution mode
Authors: Liao Honghui , Liu Yuansen , Jiang Jun , Liu Yuan , Wang Qi 
Published: September 2016

ABSTRACTIn general, epoxy resin (EP) glue mixed with a high content of flame retardants is used to coat glass fabrics layer by layer to prepare fire‐retardant printed circuit boards (PCBs). However, the addition of the flame retardants not only increases the cost but also greatly deteriorates the processability and mechanical properties of the PCBs. In this study, a gradient distribution mode of composite flame retardants was designed and applied in EP‐based PCB composites. Unlike the traditional uniform distribution mode, in which flame retardants are evenly distributed in every resin layer, the gradient mode concentrates a higher content of the flame retardants on the surface layer, and the concentrations are gradually reduced along the thickness. In this way, the surface resin can quickly form a condensed charring barrier to hold back fire; this effectively protects the underlying resin, which has lower contents of flame retardant. The results of this study show that PCB prepared by the gradient mode obtained satisfactory flame retardance (a UL94 V‐0 rating) with only a 3.5 wt % total amount of flame retardant; this value was much lower than that (6.3 wt %) of composites featuring a uniform distribution. Additionally, the gradient mode also maintained the mechanical properties of PCB better. The tensile, impact, and flexural strengths of the gradient distribution system were obviously higher than those of the uniform distribution one with the same content of flame retardant. On the basis of the mode, a more economic and efficient technology was developed to manufacture flame‐retardant layered PCB. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44369.
Electrical conductivity and transparency of polymer hybrid nanocomposites based on poly(trimethylene terephthalate) containing single walled carbon nanotubes and expanded graphite
Authors: Paszkiewicz S. , Szymczyk A. , Sui X. M. , Wagner H. D. , Linares A. , Cirera A. , Varea A. , Ezquerra T. A. , Rosłaniec Z. 
Published: September 2016

ABSTRACTSingle‐walled carbon nanotubes (SWCNT)/expanded graphite (EG)/poly(trimethylene terephthalate) (PTT) hybrid nanocomposites were prepared via in situ polymerization. Raman spectroscopy and scanning electron microscopy (SEM) were employed to determine both, purity and morphology of the nanofillers and the dispersion of nanotubes and nanosheets. The electrical and optical properties of thin polymer films based on both “single” nanocomposites and hybrid nanocomposites were studied. For PTT/SWCNT nanocomposites, results confirmed that films optical transmittance decreases as the concentration of SWCNT increases, attaining almost no optical transmittance for 0.3 wt % of nanofiller. Conversely, the electrical conductivity of nanocomposites was found to increase by increasing the nanofiller amount and the σdc values indicate that percolation occurs at a very low SWCNT content (around 0.05 wt %). In the case of PTT/SWCNT + EG nanocomposites, when the content of SWCNT is 0.05%, the hybrid system presents lower conductivity than that corresponding to the “single” nanocomposite. The incorporation of additional EG to the PTT/SWCNT nanocomposite has a small effect on the electrical conductivity but inhibits the transparency of the system. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44370.
Rheological and fire properties of a composite of unsaturated polyester resin and halogen‐free flame retardants
Authors: Kużdżał Ewa , Cichy Barbara , Kicko‐Walczak Ewa , Rymarz Grażyna 
Published: September 2016

ABSTRACTThe main subject of the present research is to determine the impact of flame retarding fillers on macroscopic properties of composites. The effect on rheological properties of composition unsaturated polyester resin (UP) and flame retardant blend (FR) consisting of expandable graphite (EG) and or not modified silica and: (1) melamine polyphosphate (MPP) with ammonium polyphosphate (APP), (2) MPP with aluminum trihydrate (ATH), (3) only MPP was examined. Next, their influence on thixotropic properties of UP was estimated. FR fillers were compared according to their grain size, specific surface, and shape factor. Rheological properties were determined by applying hysteresis loop surface and thixotropy factor measuring. For the UP + FR composition, the dependence of grain morphological parameters, such as shape factor and specific surface, on viscosity and hysteresis loop surface was determined experimentally. All of the tested composites consisting of UP + 40% FR blend exhibits high flame resistance. An addition of only 2% of modified silica to all of the FR blends caused significant enlargement of hysteresis loop surface and thixotropy index. Hence, for the next stage of the research (an industrial test of GRP pipes casted by the centrifugal method) FR blend without modified silica was chosen. A composite consisting of UP, MP, APP and EG is characterized by lower heat release rate (HRRmax) (ca. 83%) and lower TSR (ca. 80%), ALMR (55%), and MARHE (73%) in comparison to UP resin; and that UP + FR composition exhibit satisfactory rheological properties as well. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44371.
Decoration of graphene oxide nanosheets with amino silane‐functionalized silica nanoparticles for enhancing thermal and mechanical properties of polypropylene nanocomposites
Authors: Klunbud Panupong , Suktha Phansiri , Sawangphruk Montree 
Published: September 2016

ABSTRACTGraphene oxide nanosheets were decorated by amino‐silane modified silica nanoparticles. An electrostatic interaction between the negative charge of oxygen‐containing groups of graphene oxide and the positive charge of amino‐silane functional groups on the surface of silica nanoparticles plays a major role for the interfacial interaction of these two materials. The hybrid material was then used as a reinforcement in polypropylene (PP) composite. The increasing tensile strength at yield, tensile, and flexural modulus of the PP composite at a graphene oxide‐ amino‐silane silica loading content of 20 wt % are about 24.81, 55.52, and 30.35%, respectively, when compared with those of PP. It is believed that GO assists the dispersion of SiO2 nanoparticles to the polymer matrix because of its unique structure having hydrophilicity due to its oxygen functional groups and hydrophobicity owing to its backbone graphitic carbon structure. This hybrid material may also be used as the reinforcement in other polyolefins. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44382.
Durable adhesives based on electrospun poly(vinylidene fluoride) fibers
Authors: Sahay Rahul , Baji Avinash , Ranganath Anupama Sargur , Anand Ganesh V. 
Published: September 2016

ABSTRACTHerein, the fabrication of poly(vinylidene fluoride) (PVDF) fibrous membrane using electrospinning is reported and its use for dry‐adhesive applications is demonstrated. The shear and normal adhesion performance of the samples was investigated using an Instron tensile tester and an atomic force microscope (AFM) respectively. For shear adhesion measurements, the electrospun membrane was finger pressed on to a glass slide and pulled in shear mode using a tensile tester. The thickness of the electrospun membrane was varied and the effect of thickness on shear adhesion was investigated. The shear adhesion strength increased when the thickness of the samples was reduced. Shear adhesion strength of a 200 µm thick sample was determined to be approximately 0.165 N/cm. For normal adhesion measurements, a flat tipless cantilever was used to indent the sample and then retract back to measure the pull‐off force. High shear adhesion strength and normal pull‐off force recorded are attributed to the fine size of the fibers that conform to the asperities present on the surfaces of the glass slide and the AFM cantilever. The durability of the adhesive was also verified by repeating the AFM adhesion measurements over 1000 consecutive attachment–detachment cycles. The pull‐off force was seen to be constant over 1000 attachment–detachment cycles. Our results indicate that these electrospun fibrous membranes can potentially be used as reusable dry‐adhesives. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44393.
Metallo‐organic n‐type thermoelectrics: Emphasizing advances in nickel‐ethenetetrathiolates
Authors: Menon Akanksha K. , Uzunlar Erdal , Wolfe Rylan M. W. , Reynolds John R. , Marder Seth R. , Yee Shannon K. 
Published: September 2016

ABSTRACTMetallo‐organic complexes with nickel as the metal center have been shown to exhibit high electrical conductivities warranting investigation of their thermoelectric potential. A review of metallo‐organic n‐type thermoelectrics is presented with a focus on nickel‐sulfur coordination compounds. Herein, we also investigate the extent of oxidation on thermoelectric properties of poly(Ni‐1,1,2,2‐ethenetetrathiolate) (Ni‐ETT) based materials. Elemental analysis and X‐ray photoelectron spectroscopy are used to characterize samples with different air exposure times, leading to differing levels of oxidation. When blended with an inert polymer matrix, the sample exposed to air for 30 min resulted in an eight times enhancement in electrical conductivity compared to the sample exposed to air for 24 h. Furthermore, the elemental composition of the 30 min sample fit the empirical formula Ax(MC2S4) postulated in literature, while the 24 h sample does not, which we attribute to decomposition during the oxidation process and presence of disulfides. The Seebeck coefficient remains largely unchanged as a function of oxidation time, indicating that this may be a viable technique to decouple Seebeck and electrical conductivity for high‐performance organic thermoelectric materials. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44402.
Reaction‐induced phase separation and resulting thermomechanical and surface properties of epoxy resin/poly(ethylene oxide)–poly(propylene oxide)–poly(ethylene oxide) blends cured with 4,4′‐diaminodiphenylsulfone
Authors: Parameswaranpillai Jyotishkumar , Krishnan Sidhardhan Sisanth , Jose Seno , Siengchin Suchart , Pionteck Jürgen , Magueresse Anthony , Grohens Yves , Hameed Nishar 
Published: September 2016

ABSTRACTWe investigated the phase separation, cure kinetics and thermomechanical properties of diglycidyl ether of bisphenol‐A/4,4′‐diaminodiphenylsulfone/poly(ethylene oxide)–poly(propylene oxide)–poly(ethylene oxide) (PEO–PPO–PEO) triblock copolymer (TBCP) blends. Fourier transform infrared spectroscopy, differential scanning calorimetry, and atomic force microscopy revealed that the blends exhibited heterogeneous phase morphology in which the TBCP formed dispersed domains in epoxy matrix, due to reaction induced phase separation. A fraction of phase‐separated PEO phase underwent partial crystallization whereas another fraction formed interphases between the dispersed domains and epoxy matrix. Moreover, the dispersed PEO chains improved the compatibility and interfacial adhesion between the matrix and domains and, consequently, significantly improved the mechanical properties of epoxy resin. Furthermore, the thermal degradation studies and contact angle measurements disclosed that the dispersed domains were well protected by the epoxy matrix. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44406.
Surface photochemical graft polymerization of acrylic acid onto polyamide thin film composite membranes
Authors: Hong Anh Ngo Thu , Tran D. T. , Hung Dinh Cuong 
Published: September 2016

ABSTRACTSurface modification is an effective approach to enhance the properties of polymeric membranes. In this work, the UV‐photo‐induced graft polymerization of acrylic acid (AA) onto the surfaces of polyamide thin film composite (TFC‐PA) membranes was carried out using an immersion method performed under ambient conditions. The experimental results indicate that the membrane surface becomes more hydrophilic because of the appearance of new carboxylic groups on the surface after the modification. This reduces the water contact angle and increases the water permeability compared with the unmodified membrane. The membrane surface is relatively compact and smooth due to the formation of the polymeric AA‐grafted layer. The separation performance of the modified membrane is improved with enhancements of the permeate flux and the retention of humic acid from aqueous feed solutions compared with those of the unmodified membrane. The fouling resistance of the membrane is also improved because of the higher maintained flux ratios and the lower irreversible fouling factors for the removal of various organic compounds from feed solutions. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44418.
pH‐responsive core crosslinked polycarbonate micelles via thiol‐acrylate Michael addition reaction
Authors: He Jingwen , Xia Yingchun , Niu Yile , Hu Ding , Xia Xinnian , Lu Yanbing , Xu Weijian 
Published: September 2016

ABSTRACTA facile method for the construction of pH‐responsive core crosslinked micelles (CCLMs) based on polycarbonate was developed. Biodegradable amphiphilic block copolymer monomethoxy poly(ethylene glycol)‐b‐Poly(AC) (mPEG‐b‐poly(AC)) with pendant acrylate group was synthesized by means of ring opening polymerization of acryloyl carbonate (AC). Then CCLMs were obtained via thiol‐acrylate Michael addition reaction between the pendant acrylate group in the hydrophobic block and the crosslinker 1,6‐hexanedithiol. DLS results showed that the CCLMs prepared from mPEG‐b‐poly(AC)25 were more stable than uncrosslinked micelles (UCLMs) upon dilution by 10‐fold DMF. Model drug Coumarin 102 was then encapsulated into the micelles. The pH‐responsive release of coumarin 102 from the CCLMs was demonstrated by fluorescence spectroscopy. The core crosslinked polycarbonate micelles have a potential as efficient intracellular smart drug delivery platforms. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44421.
Barrier properties of poly(lactic acid)/cloisite 30B composites and their relation between oxygen permeability and relative humidity
Authors: Bartel Melanie , Remde Helmut , Bohn Andreas , Ganster Johannes 
Published: September 2016

ABSTRACTPoly(lactic acid) based nanocomposite films were prepared by melt compounding and subsequent flat film extrusion. After characterizing the nanocomposites with the help of transmission electron microscopy and wide angle X‐ray diffraction to estimate the nanoclay distribution in the matrix material, the oxygen and water vapor permeability of untreated and annealed nanocomposite films were analyzed. A reduction to 34% of both permeability values could be realized by the addition of 6 wt % Cloisite 30B and subsequent annealing to realize maximum crystallinity. Experimental permeability as a function of nanoclay concentration was successfully described by the Tortuous Path Model. In addition, the correlation between oxygen permeability and relative humidity was analyzed for pure PLA and PLA based nanocomposite films. For both untreated films oxygen permeability decreased almost linearly between 0% and 96% RH to approximately 70% of the respective value for the dry sample. Annealed PLA films, on the other hand, showed a similar behavior up to 70% RH but an increase in oxygen permeation for higher moisture content. This is explained by the observed reduction in crystallinity generating more free volume, bringing the system closer to the amorphous case where permeability is generally higher. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44424.
Effect ofTween 80 on morphology and performance of poly(L‐lactic acid) ultrafiltration membranes
Authors: Jiang Bin , Wang Baoyu , Zhang Luhong , Sun Yongli , Xiao Xiaoming , Yang Na , Dou Haozhen 
Published: September 2016

ABSTRACTPoly(L‐lactic acid) (PLLA) ultrafiltration (UF) membrane was fabricated by immersion precipitation method using Tween 80 as an additive. Membrane structure was characterized by scanning electron microscopy (SEM), porosity and pore size measurement, and atomic force microscopy (AFM). Membrane performance was evaluated by pure water flux, molecular weight cut‐off, and tensile test. It was found that the addition of Tween 80 into the casting solution significantly increased the permeability and molecular weight cut‐off of membrane. Tensile test confirmed that the as‐prepared PLLA membranes exhibited acceptable mechanical properties for ultrafiltration. Further, the role of Tween 80 in the process of membrane formation was analyzed and proposed. The addition of Tween 80 favored the formation of larger pores by interrupting the polymer chain entanglement and improving the miscibility between solvent and coagulant. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2017,134, 44428.
Self‐supporting‐film from starch, poly(vinyl alcohol), and glutaraldehyde: Optimization of composition using response surface methodology
Authors: Sen Chandani , Das Madhusweta 
Published: September 2016

ABSTRACTUse of starch based biodegradable packaging film can partially reduce the landfilling problem from non‐biodegradable petroleum based alternatives. The aim of this work was to optimize raw material blend composition containing corn‐starch (CS), and low amount of poly(vinylalcohol) (PVA) and glutaraldehyde (GA) to produce self‐supporting‐film (SSF), using response surface methodology. Rotatable central composite design was used to evaluate the effect of CS (6.25–7.50), PVA (0.00–1.25), and GA (0.00–1.25), in g/100 mL of the blend, on tensile strength (TS), percent elongation (%El), and water vapor permeability (WVP) of the film. The most significant (p < 0.01/0.05) factors were: CS and GA for TS, CS and PVA for El, and PVA for WVP. The SSFs were thin, flexible and transparent; the optimum composition (g/100 mL) to maximize TS and El, and minimize WVP was 7.50 (CS), 0.875 (PVA), and 0.125 (GA), which produced SSF showing TS: 11.66 MPa, %El: 8.56, and WVP: 0.13 g mm/m2 /kPa/h. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44436.
Dual‐Confined Sulfur Nanoparticles Encapsulated in Hollow TiO2 Spheres Wrapped with Graphene for Lithium–Sulfur Batteries
Authors: Fan Haining , Tang Qunli , Chen Xiaohua , Fan Binbin , Chen Shanliang , Hu Aiping 
Published: September 2016

AbstractLithium–sulfur (Li−S) batteries are attractive owing to their higher energy density and lower cost compared with the universally used lithium‐ion batteries (LIBs), but there are some problems that stop their practical use, such as low utilization and rapid capacity‐fading of the sulfur cathode, which is mainly caused by the shuttle effect, and the uncontrollable deposition of lithium sulfide species. Herein, we report the design and fabrication of dual‐confined sulfur nanoparticles that were encapsulated inside hollow TiO2 spheres; the encapsulated nanoparticles were prepared by a facile hydrolysis process combined with acid etching, followed by “wrapping” with graphene (G−TiO2@S). In this unique composite architecture, the hollow TiO2 spheres acted as effective sulfur carriers by confining the polysulfides and buffering volume changes during the charge‐discharge processes by means of physical force from the hollow spheres and chemical binding between TiO2 and the polysulfides. Moreover, the graphene‐wrapped skin provided an effective 3D conductive network to improve the electronic conductivity of the sulfur cathode and, at the same time, to further suppress the dissolution of the polysulfides. As results, the G−TiO2@S hybrids exhibited a high and stable discharge capacity of up to 853.4 mA h g−1 over 200 cycles at 0.5 C (1 C=1675 mA g−1) and an excellent rate capability of 675 mA h g−1 at a current rate of 2 C; thus, G−TiO2@S holds great promise as a cathode material for Li−S batteries.