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Nitrogen and oxygen co-doped hierarchical porous carbons (NOPCs) is prepared by the pyrolysis of polyethylene glycol-200 (PEG) and triazine carbon forming agent (CFA) using MgO as template. The PEG/CFA/MgO mixtures were compacted to form a consolidate solids, which play a key role for the formation of NOPCs. The morphology, microstructure, phase structure, textural property, surface element composition and thermal stability properties of NOPCs were investigated. It was demonstrated that the NOPCs exhibit hierarchical porous structure, high specific surface area (the largest SBET of 1244 m2/g), and abundant mesopore structures without any activation. Benefiting from the unique porous structure and rich heteroatom functional group (1.34 at % N and 20.33 at % O), the NOPC-900 electrode shows a specific capacitance of up to 347 F/g at 0.5 A/g and can keep 187 F/g even at 50 A/g. Moreover, the NOPC-900 electrode shows good cycle life with capacitance retention of 90% after 10,000 cycles. This paper provides a new, convenient way to construct hierarchical porous carbon materials for super capacitors.

Three-dimensional graphene-like materials can effectively prevent the restacking of graphene layers and show tremendous potential applications in practice. In the present work, foamed graphene flakes (FGs) were easily prepared by a one-step pyrolysis of polyethylene glycol-200 (PEG)/MgO composites, and they were successfully applied in supercapacitors and lithium-ion batteries (LIBs). The FGs consisted of a large number of foamed flakes, and each flake was made up of 3 to 10 graphene layers. By changing the weight ratio of PEG/MgO, the specific surface area, porosity, and graphitization of the FGs could be adjusted. As electrode materials of supercapacitors, FGs from the PEG/MgO at a weight ratio of 1 : 1.5 showed the highest areal capacitance of 29.5 μF cm−2 and a retention rate of 92%. As the anode materials of LIBs, FGs from PEG/MgO at a weight ratio of 4 : 1.5 had a reversible discharge capacity of 787 mA h g−1 at a current density of 0.2C, and showed excellent rate performance and cycling stability. These FGs have significant potential for practical application in electrochemical energy storage.

The hard-template method belongs to an effective route for preparing porous carbon materials with ideal hierarchical pores. In this work, a kind of hierarchical porous carbon (HPC) with high gravimetric and volumetric capacitance is fabricated by the use of Al–Cu double hydroxides (Al–Cu DHs) as hard templates and polyethylene glycol-200 as carbon precursors. It is found that the Al/Cu molar ratio has a profound influence on the morphology and composition of Al–Cu DHs and the obtained hierarchical porous architecture of HPCs owing to the template and catalyst functions of both Cu and Al2O3. For Al/Cu molar ratios of 5:1 and 7:1, the prepared HPC-05 and HPC-07 display a large specific surface area and appropriate hierarchical porous architecture. They can be used as the electrode materials of supercapacitors without any activation. The HPC-05 exhibits gravimetric capacitance (296.9 F g−1) and high volumetric capacitance (183.3 F cm−3). Moreover, the capacitance retention is 105% in 1 M Na2SO4 electrolyte with an ultrahigh gravimetric energy density of 16.32 W h kg−1 and a volumetric energy density of 10.09 W h l−1. This paper provides a tunable double-hydroxide-template way to construct HPC materials with high gravimetric and volume capacitance.

The hierarchical porous carbons (HPCs) are considered as promising supercapacitor electrode materials. However, most of them suffer from low volumetric capacitance values and rate performance. In the work, a kind of MgAl-layered double hydroxides (LDHs) templates is synthesized by co-precipitation and recrystallization strategy. It is found that the recrystallization can effectively decrease the overall dimensions and adjust the pore size of LDHs. By the use of LDHs as templates and polyethylene glycol-200 (PEG-200) as carbon precursors, a series of HPCs are synthesized. The HPCs basically copy the morphology of LDHs, and their electrochemical properties are influenced significantly by the recrystallization time of LDHs. With the 24h recrystallization of LDHs, the obtained HPC shows the highest compact density of 0.78 g cm−3. It delivers the volumetric capacitance of 183 F cm−3 and retains outstanding rate stability of 81.54% of initial capacitance when current density is increased to 50 times. Moreover, the volumetric energy density of 15.11 Wh L−1 (19.38 Wh kg−1) is achieved at the power density of 373.2 W L−1. This work provides a simple route to fabricate HPCs with high volumetric capacitance and rate performance.

The Ni, Ni–Mo, Ni–Mg, and Ni–Mo–Mg catalysts were systematically explored for the one-step conversion of polystyrene (PS) into carbon nanotubes (CNTs). The catalysts were characterized in the phase structure, morphology, reducibility, and carbonization performance. It was found that the Mo contributed to the small catalyst particle growth by the formation of NiMoO4 phase. The addition of Mg had no effect on catalyst particle sizes but effectively controlled the carbon solubility and led to the growth of CNTs by the generation of NiMgO2. Finally, we demonstrated that the Ni–Mo–Mg catalysts showed the most efficient for the conversion of PS into CNTs owing to the individually synergetic effect of Mo and Mg elements. Besides catalysts, the degradation additives and the carbonization temperature were also discussed for their effects on the carbonization of PS. It is believed that the work provides potential for the conversion of PS waste into CNTs.

Fluorometric “turn-on” glucose detection is presented that is based on the Fenton reaction which can trigger the generation of Ag nanoclusters (Ag NCs). Oxidation of D-glucose by glucose oxidase generates H2O2. Reactive radicals are formed from the Fenton reaction of H2O2 and Fe2+. These radicals initiate the polymerization of methacrylic acid to form poly(methacrylic acid) which is used as a template to generate fluorescent Ag NCs in situ by illumination with UV light. The increase in Ag NCs fluorescence intensity can be used to quantify glucose concentration. The sensing approach employed here provides a new strategy for the determination of glucose selectively.

A kind of junction-soldered CNT networks has been successfully prepared just by adding a kind of carbon black (CB) into the catalytic carbonization of polypropylene (PP). Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were applied to measure the morphology and microstructures of CNT networks. X-ray diffractometer (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and Thermogravimetric analysis (TGA) were used to characterize the phase structures, surface compositions and thermal stability of the CNT networks. Results demonstrated that the added CB-1 not only had a positive effect on the CNT yield of PP/Ni−Mo-Mg, but also soldered the as-synthesized CNTs to form a type of novel CB-soldering CNT networks. By analyzing the formation mechanism, the increased effect on CNT yield should come from its radical trapping ability, while the soldering performance is heavily dependent on the size of CB.

A simple and general approach is reported for the direct growth of carbon nanotubes (CNTs) on macroscopic carbon substrates. Two typical geometries of biomass materials, cellulose fibers or rice husks, are chosen to act as the precursor of carbon substrates, and commercial polypropylene (PP) pellets are used as the carbon source of CNTs with the presence of Ni–Mo–Mg catalysts. This simple and general strategy was realized by a direct pyrolyzation of the PP blends containing biomass materials and Ni–Mo–Mg catalysts in a chemical vapor deposition device at 800 °C under nitrogen’s protection. The carbon products were characterized by various techniques such as X-ray diffractometer, transmission electron microscopy, scanning electron microscopy, Raman spectroscopy, and thermogravimetric analysis. Results show that the CNTs are successfully grown on the macroscopic carbon substrate derived from cellulose fibers or rice husks, whereas the addition of biomass materials as carbon precursors has to some extent an influence on the morphology of CNTs in the carbon products.

We demonstrate the successful synthesis of carbon nanotubes (CNTs) on in situ formed siliceous micro-flakes by one-step pyrolyzation of polypropylene/(methyl MQ silicone)/Ni–Mo–Mg blends. An appropriate concentration of methyl MQ silicone in blends acts as a key factor for the formation of this kind of Si–C nanohybrid. CNTs growing on nano- or micro-scale siliceous flakes were acquired by directly pyrolyzing polypropylene with 12 wt% methyl MQ silicone and 5 wt% catalysts. The product was systematically characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and thermogravimetric analysis. A formation mechanism was also proposed. A tentative application for the obtained Si–C nanohybrids as anode materials of lithium-ion batteries was evaluated. Excellent electrochemical performance including cycle capacity and coulombic efficiency was confirmed. The current approach provides a very promising avenue for fabricating Si–C nanohybrids, studies of further applications of which are under way.

Plastics used as carbon source present a sustainable and environmentally benign route for the preparation of carbon nanotubes (CNTs); however, the current catalysts basically take effect on a certain type of plastics. Herein, a significantly universal carbonization performance of Ni-Mo-Mg catalysts has been created for polypropylene (PP), polyethylene (PE), polystyrene (PS), and their blends with the highest CNT yields of 26.24%, 28.36%, 18.39%, and 31.66%. With the further introduction of a universal synergistic agent (nanosized carbon black), the maximum CNT yields of 53.56%, 65.95%, 41.85%, and 59.83% from PP, PE, PS, and their blends were achieved, respectively. The morphology, microstructure, and the graphitization of above CNTs were measured by scanning electron microscopy, transmission electron microscopy, X-ray diffractometer, Raman spectroscopy, and high-resolution transmission electron microscope. Results demonstrated that the addition of carbon black could further improve the morphology of CNTs and enhance the graphitization of CNTs. Within three polyolefins, the PS offered the highest graphitization of CNTs. Finally, the highly universal carbonization performance of Ni-Mo-Mg catalysts and the universal synergistic effect were also discussed. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44647.

The gesture associated with the language can help to strengthen the effect of the natural language expression. Gesture animation synthesis associated with language is the focus and difficulty of virtual human interaction in virtual reality. We studies how to maintain motion details and motion smoothing during gesture animation synthesis. By analyzing the related technology and theory of gesture animation synthesis, this paper puts forward the gesture animation synthesis method based on keyframe interpolation among movement primitive elements. The method avoids the loss or interruption of the motion object and effectively improves the sense of reality of the gesture animation synthesis.

This article presents a novel investigation on the Mo/Mg/Ni/O catalysts (Nmm-cats) with which the noncharring polyolefins are basically transferred to the charring polymers under forced flaming conditions and the flame retardancy of polyolefins is improved dramatically. The results of model charring experiments show that when appropriate Mo/Mg/Ni molar ratio is adopted and only 3% Nmm-cats is blended, the Nmm-cats belong to high-efficient charring catalysts that can deposit 56 and 64 wt % of volatile products in-situ from linear low-density polyethylene (LLDPE) and polypropylene (PP), respectively. The charring properties are characterized by scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy; and the char-forming mechanisms are analyzed by wide-angle X-ray diffraction experiment. The improvement in flammability properties for LLDPE and PP is demonstrated by using a cone calorimeter. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

A novel silicone-containing flame retardant (HSOBA) synthesized from hydrogen-containing silicone oil and Bisphenol A via a simple approach has been incorporated into polycarbonate (PC) matrix to study its effects on the flame retardancy. The flame retardancy of PC/HSOBA composites is investigated by limiting oxygen index (LOI), vertical burning tests (UL-94), and cone calorimeter measurement. The LOI value of the composites is 31.7 and the UL-94 rating reaches V-0, when the content of HSOBA is 3 wt %. Cone calorimeter data confirm that the HSOBA acts as an effective additive functioning both as flame retardants and as smoke suppressant. Evolution of the thermal behaviors of the composites tested by TGA, the morphological structures, and the constituent of char residue after LOI tests characterized by scanning electronic microscopy-energy-dispersive X-ray analysis were used to explain the possible flame-retardant mode. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

The effect of combination between a trace of halogenated compounds (such as ferric chloride and ammonium bromide) and Ni 2 O 3 particles on the carbonization of polypropylene (PP) was investigated during combustion. The results showed a synergistic catalysis of combined halogenated compounds with Ni 2 O 3 in promoting the formation of the residual char during combustion. The investigation on the promotion mechanism showed that halide radical releasing from halogen-containing additives worked as a catalyst to accelerate dehydrogenation–aromatization of degradation products of PP, which promote the degradation products to form the residual char catalyzed by nickel catalyst. The results of GC and GC/MS confirmed that halogenated compounds could accelerate dehydrogenization and aromatization of degradation products of PP. The morphological observation showed that longer fiber-like structure was formed in the residual char of PP/halogenated compound/Ni 2 O 3 composites comparing with PP/Ni 2 O 3 composite. As a result, the presence of a trace amount of halogenated compounds could significantly improve the flame retardancy of PP/Ni 2 O 3 composites, which is proved by cone calorimeter tests.

In a simple device, two kinds of zeolites were successfully used as synergistic additive to promote formation of the multi-walled carbon nanotubes (MWNTs) from polypropylene (PP) via combustion. More importantly, this kind of process may potentially act as a new approach for recycling plastic wastes, because it could effectively transfer polyolefin wastes into valuable carbon materials. Experimental results demonstrated that the higher quality of MWNTs can be obtained from the mixture (PP/H-Beta/Ni2O3) than that from the mixture (PP/H-ZSM-5/Ni2O3). At the same time, the yield of MWNTs from PP/H-ZSM-5/Ni2O3 system is much lower than that from PP/H-Beta/Ni2O3 under the same condition. The reason for the different effects of both types of zeolites on the morphology and the yield of the MWNTs was analyzed. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

Combination of Ni2O3 and solid acid with Bronsted acid sites and Lewis acid sites (such as HZSM-5 and H-beta) could dramatically improve fire retardancy of polyolefin, including polypropylene and linear low-density polyethylene. This is mainly attributed to the formation of a large amount of residual char from degradation products of polyolefin in the intermediate stage of combustion. Thus, the amount of flammable components diffusing into the flame zone was small.

Three kinds of organically modified Na+-montmorillonites (OMMTs), including two kinds of octadecylammonium modified montmorillonite with different contents of octadecylammonium and a kind of sodium dodecylsulfonate (SDSo) modified montmorillonite, were used to prepare polyamide 12 (PA12)/OMMT nanocomposites. Effects of the modifiers on degradation and fire retardancy of PA12/OMMT nanocomposites were investigated. Acid sites formed in cationic surfactant modified MMT via Hoffman decomposition could accelerate degradation of PA12 at high temperature. However, catalytic effect of the acid sites on carbonization of the degradation products promoted char barrier formation, which reduced heat release rate (HRR). Higher content of cationic surfactant in OMMT is beneficial to fire retardancy of PA12 nanocomposites and the dispersion states of OMMT have assistant effects. In contrast, Na+-montmorillonite (Na-MMT) and anionic surfactant modified MMT (a-MMT) could not form acid sites on the MMT layers; in this case, fire retardancy of PA12/Na-MMT appears to have no improvement and PA12/a-MMT appears to have limited improvement.

The degradation and flame retardancy of polypropylene/organically modified montmorillonite (PP/OMMT) nanocomposite were studied by means of gas chromatography-mass spectrometry and cone calorimeter. The catalysis of hydrogen proton containing montmorillonite (H-MMT) derived from thermal decomposition of (alkyl) ammonium in the OMMT on degradation of PP strongly influence carbonization behavior of PP and then flame retardancy. Bronsted acid sites on the H-MMT could catalyze degradation reaction of PP via cationic mechanism, which leads to the formation of char during combustion of PP via hydride transfer reaction. A continuous carbonaceous MMT-rich char on the surface of the burned residues, which work as a protective barrier to heat and mass transfer, results from the homogeneous dispersion of OMMT in the PP matrix and appropriate char produced.

The effects of both organically modified montmorillonite (OMMT) and Ni(2)O(3) on the carbonization of polypropylene (PP) during pyrolysis were investigated. The results from TEM and Raman spectroscopy showed that the carbonized products of PP were mainly multiwalled carbon nanotubes (MWNTs). Surprisingly, a combination of OMMT and Ni(2)O(3) led to high-yield formation of MWNTs. X-ray powder diffraction (XRD) and GC-MS were used to investigate the mechanism of this combination for the high-yield formation of MWNTs from PP. Brønsted acid sites were created in degraded OMMT layers by thermal decomposition of the modifiers. The resultant carbenium ions play an important role in the carbonization of PP and the formation of MWNTs. The degradation of PP was induced by the presence of carbenium ions to form predominantly products with lower carbon numbers that could be easily catalyzed by the nickel catalyst for the growth of MWNTs. Furthermore, carbenium ions are active intermediates that promote the growth of MWNTs from the degradation products with higher carbon numbers through hydride-transfer reactions. The XRD measurements showed that Ni(2)O(3) was reduced into metallic nickel (Ni) in situ to afford the active sites for the growth of MWNTs.

Multi-walled carbon nanotubes (MWCNTs) were efficiently synthesized by catalytic combustion of polypropylene (PP) using nickel compounds (such as Ni2O3, NiO, Ni(OH)2 and NiCO3 · 2Ni(OH)2) as catalysts in the presence of organic-modified montmorillonite (OMMT) at 630–830 °C. Morphologies of the sample undergoing different combustion times were observed to investigate actual process producing MWCNTs by this method. The obtained MWCNTs were characterized by X-ray diffraction (XRD), transmission electron microscope and Raman spectroscopy. The yield of MWCNTs was affected by the composition of PP mixtures with OMMT and nickel compounds and the combustion temperature. The proton acidic sites from the degraded OMMT layers due to the Hoffman reaction of the modifiers at high temperature played an important role in the catalytic degradation of PP to supply carbon sources that are easy to be catalyzed by nickel catalyst for the growth of MWCNTs. The XRD measurements demonstrated that the nickel compounds were in situ reduced into the Ni(0) state with the aid of hydrogen gas and/or hydrocarbons in the degradation products of PP, and the Ni(0) was really the active site for the growth of MWCNTs. The combination of nickel compounds with OMMT was a key factor to efficiently synthesize MWCNTs via catalytic combustion of PP.

Carbon black particles were incorporated into the polypropylene (PP) in combination with Ni–Mo–Mg catalysts to investigate their influences on the carbonization and flame retardancy of PP. The results demonstrate that the carbon black exhibited a very positive effect on the char yield of PP in a pyrolyzation experiment with different temperatures. For pyrolyzation at 750 and 550°C, the PP/5% Ni–Mo–Mg/5% carbon black blends gave 56 and 37.1% char yields, respectively. Scanning electron microscopy, transmission electron microscopy results, and direct optical observations from designed experiments all demonstrated a combination of carbon black with growing carbon nanotubes (CNTs) for the generation of char with integrated and compact structures. Cone calorimeter and limited oxygen index tests confirmed that the integration of carbon black particles and CNTs led to a significant improvement in the flame retardancy of PP. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43034.

Supported nickel catalyst (Ni-Cat) was used as a catalyst to improve the flame retarclancy of intumescent flame-retardants (IFR) systems based on ammonium polyphosphate and pentaerythritol (PETOL) in polypropylene (PP) matrix. Limited oxygen index (LOI), UL-94 rating, and thermogravimetric analysis were used to characterize the flame retardancy and thermal stability of the PP systems, and field emission scanning electron microscopy (FE-SEM) and Fourier transformed infrared spectroscopy (FTIR) were used to analyze the microstructure and composition of the chars formed during measuring LOI value and after combustion at 800 degrees C. The catalytic effect of NiCat was shown in an increase of LOI, a change in the char microstructure, and improvement of the thermal stability in the PP systems, which result from the synergistic effect of Ni-Cat and IFR. The results from FE-SEM and FTIR spectra of the char can explain how this synergistic effect happened.

In the experiment, the furfural added compound agent was applied to treat catalytic cracking slurry oil in order to utilize the saturated hydrocarbon and condensed-nuclei aromatics reasonably and soundly. The added agent could improve the dissolubility and selectivity of furfural and enhance the recovery and quality of treated oil. The optimum condition was as follows: compound ratio was 0.5:1; the added quantities were 8% relative to furfural volume; the temperature was 50°C; the solvent/oil ratio was 0.5:1. Under the condition, compared with that of furfural extraction, the recovery of treated oil was increased 14.8 wt%, the quality of treated oil also had been improved to some extent, and thus, the treated oil could be used as good stockfeed of catalytic cracking. The extract oil contained abundant condensed-nuclei aromatics, which could be used as good stockfeed to produce a high value-added chemical engineering product.

We demonstrated an efficient improvement of activity of Ni catalysts by combining with Mo and Mg elements, by which massive growth of multiwalled carbon nanotubes (MWNTs) with straight and double h...

Carboxyl-containing polysiloxane (LCCP) has been successfully applied in the flame retardancy of polycarbonate (PC). The LCCP was synthesized by hydrosilylation and condensation reaction. The presence of carboxyl groups has been demonstrated to be crucial to provide high flame retardant effectiveness. The flame retardancy of LCCP–PC composites is investigated by limiting oxygen index (LOI), vertical burning tests (UL-94). At the mole ratio of diethoxymethyl (1-propionyloxy) silane/diethoxydimethylsilane = 8/100 in LCCP(3), the best flame retardant performance of LCCP-PC composites was obtained. The LOI value of the composites is 38.5 and the UL-94 rating reaches V-0 when the content of LCCP(3) is as low as 0.5 wt %. Evolution of the thermal behaviors of the composites tested by thermogravimetric analysis shows that addition of LCCP(3) in PC can reduce the degradation speed of PC and induce a reduction of the initiated decomposition temperature of PC. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014, 131, 39814.

A model experiment was done to clear the formation mechanism of protective layers during combustion of polypropylene (PP)/organically modified montmorillonite (OMMT) nanocomposites. The investigation was focused on the effects of annealing temperature on the structural changes and protective layer formation. The decomposition of OMMT and degradation of PP/OMMT nanocomposites were characterized by means of thermogravimetric analysis (TGA). The structural evolution and composition change in the surface region of PP/OMMT nanocomposites during heating were monitored by means of X-ray photoelectron spectroscopy (XPS), ATR-FTIR and field emission scanning electron microscopy (FESEM). The results showed that the formation of the carbonaceous silicate barrier in the surface region of PP/OMMT nanocomposites resulted from the following three processes: (1) The formation of strong acid sites on the MMT sheets, which could promote the degradation of PP and the carbonization of its degradation products; (2) The gases and gas bubbles formed by decomposition of the surfactant and degradation of PP, which pushed the molten sample to the surface; (3) The degradation of PP and the carbonization of the degradation products, which led to accumulation of MMT sheets tightly linked by the char in the surface region.

Silica-gel nanowire/Na+-montmorillonite (Na+-MMT) nanocomposites were prepared by the in situ sol-gel process of tetraethyl orthosilicate (TEOS) in the presence of Na+-MMT and ammonia as catalyst. Microstructure characterization of the nanocomposites was done by SEM, , EDX, XRD and FTIR. It was found that a lot of silica-gel nanowires grew along the edges of Na+-MMT. The combination between the nanowires and Na+-MMT was accomplished via polycondensation of the hydrolyzed TEOS and the edge-OH groups of Na+-MMT.