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Ultrasmall Fe2P quantum dots (Fe2P QDs) are in situ self-exsolved from attapulgite (ATP) nanofibers by a low-temperature phosphidation method and the resulting Fe2P QDs/ATP has been shown to be an active, durable, and versatile H2 evolution cocatalyst.

The PCE was grafted onto manufactured sand to produce better dispersed particles, which can improve the performance of cement-based materials.

In order to improve the smoke suppression of silicone oil, relatively high nitrogen content silicone oil was synthesized by the raction of dicyandiamide (DCD) and epoxy-terminated silicone oil (ETSO) and named DCDSO. The molecular structure of DCDSO was characterized by fourier transform infrared spectrometer (FT-IR) and nuclear magnetic resonance spectrometer (NMR). The flame ignition and cone calorimetry test (CCT) were used to investigate the smoke suppression effect of DCDSO. The results showed that the introduction of DCD significantly improved the smoke suppression performance of DCDSO. When the molar ratio of the epoxy group in ETSO and the primary amino group in DCD was 1:1.3, the flame height and the total smoke production reduced 77% and 53.73%, respectively. Thermogravimetric analysis (TGA), thermogravimetric infrared analysis (TG-IR) and thermal field emission scanning electron microscopy (SEM) were used to explore the mechanism of smoke suppression. The mechanism of smoke suppression is that the introduction of DCD reduces the rearrangement decomposition, promotes the free radical oxidation decomposition and the formation of condensed phase, and thus reduces the generation and release of smoke.

Surface-modified Al2O3-epoxy reacts with Al2O3–NH2 to form clusters that reduce the viscosity of electronic potting composites.

Melamine-formaldehyde (MF)rigid foams with high closed cell content were prepared via oven heating process, using MF prepolymer prepared from melamine and paraformaldehyde as a matrix, cyclohexane as the foaming agent, dimethyl silicon oil as the foam stabilizers, hydrochloric acid as the catalyst. The effect of MF prepolymer viscosity, foaming temperature, amount of catalyst on morphology, closed cell content, apparent density, water absorption and compressive strength of MF rigid foams were systematically studied. The optimized foaming conditions are as follows: the viscosity of MF prepolymer ranges from 35 Pa·s to 45 Pa·s, the foaming temperature is 125°C and the content of the catalyst is 0.65 wt%. The as-prepared MF foams showed the best comprehensive performance with closed cell content of 83.5%, apparent density of 62 kg·m−3, water absorption of 12.0%, compressive strength of 292kPa, thermal conductivity of 0.033 W m−1 K−1 and limiting oxygen index (LOI) of 36%. Compared to conventional organic foams, MF rigid foams possess low water absorption, excellent thermal insulation and flame retardancy due to high closed cell content, and can be expected to be used as thermal insulation material for building exterior walls.

The objective of this work is to investigate the effects of 17-4pH stainless steel powders interaction on properties of feedstocks. γ-aminopropyltriethoxy silane (KH550), γ-(2,3-epoxypropoxy)propyltrimethoxy silane (KH560), propyltrimethoxy silane (N313) were used to modify 17-4pH stainless steel powders, and described as KH550-m, KH560-m and N313-m with amino, epoxy and propyl group, respectively. The properties of feedstocks prepared from the pristine, KH550-m, KH560-m and N313-m were compared with that of equal amount of KH550-m and KH560-m (KH550-m/KH560-m). The experimental results revealed that the critical solids loading, density and melt flow rate of KH550-m/KH560-m feedstocks were 62.8 vol%, 5.24 g/cm3 and 51.42 g/10 min, respectively, which were higher than that of others. Besides, the debinded parts shape retention of KH550-m/KH560-m was also better than others. The good properties of KH550-m/KH560-m feedstocks originate from the strong interaction between KH550-m and KH560-m, which comes from the reaction and hydrogen bond between amino group and epoxy group.

Toughing melamine-formaldehyde (MF) rigid closed-cell foams were prepared by using ethylene glycol (EG) and carbon fiber (CF) as composite toughening agents. The pulverization rate, compressive strength, bending strength, cellular structure, closed-cell ratio, water absorption ratio, thermal conductivity, thermal stability, limiting oxygen index (LOI), and char yield were characterized to study the morphology, mechanical, thermal, and fire-retardant properties of as-prepared toughing MF rigid foams. The pulverization rate result showed that introduction of composite modifier can obviously improve the toughness of MF rigid foams. The cellular structure, closed-cell ratio, and water absorption results showed that the addition of EG/CF can increase the closed-cell ratio and control the cell size of MF rigid foams. The compressive strength and bending strength results showed that the incorporation of composite modifier of MF rigid foams dramatically improved the mechanical properties. The LOI, char yield, and thermal stability results showed that the toughing MF rigid foams remained more intact char skeleton with flame-retardant effect, thus reducing the fire hazards. The as-prepared toughing MF rigid foams showed the best comprehensive performance with pulverization rate of 5.21%, compressive strength of 355.3 kPa, bending strength of 0.44 MPa, closed-cell ratio of 79.1%, water absorption of 9%, thermal conductivity of 0.031 W m−1 K−1, and LOI of 39.6%. Compared with unmodified MF rigid foams, toughing rigid closed-cell MF foams possess excellent pulverization rate, compressive strength, bending strength, cellular structure, thermal insulation, and flame retardancy.

High heat resistant hydroxyl silicone oil with boron and sulfoxide in backbone (HSOBS) was synthesized by copolymerizing of hydroxyl polyborosiloxane oil (HPBSO) with thionyl chloride (SOCl2). The molecular structure of HSOBS was confirmed by Fourier-transform infrared spectroscopies (FT-IR) and nuclear magnetic resonance (1H-, 11B- and 29Si-NMR) spectroscopies. The thermogravimetric analysis (TGA) results showed that incorporation of sulfoxide group in backbone obviously improved the heat resistant of HSOBS. The temperature at 5% mass loss (T5) and maximum decomposition rate (Tmax) of HSOBS-1 were 490 °C and 590 °C, respectively. The thermal degradation activation energy (Ea) was systematically studied by the Flynn-Wall-Ozawa method, and the Ea of HSOBS was higher than that of HPBSO.

Heat dissipation has become a key problem for highly integrated and miniaturized electronic components. High thermal conductivity, good flowability and low coefficient of linear thermal expansion (CLTE) are indispensable performance parameters in the field of electronic potting composite materials. In this study, spherical alumina (Al

The unsaturated modified linoleate based on linoleic acid (LA) was synthesized by a three-step reaction. The linoleic acid was first reacted with glycidyl methacrylate (GMA), then the resulting pro...

In this work, γ-aminopropyltriethoxy silane (KH550) and γ-(2,3-epoxypropoxy)propyltrimethoxy silane (KH560) were used to modify BN and Al2O3, and described as KH550-BN and KH560-Al2O3 with amino and epoxy group on surface, respectively. KH550-BN and KH560-Al2O3 were filled in polypropylene (PP) matrix by twin-screw extruder. The thermal conductivity of composites increased with increasing catalyst dosage, material residence time in barrel and homogenization section temperature of twin-screw extruder. Hybrid fillers with semi core-shell structure were formed by KH550-BN in-situ reacting with KH560-Al2O3 though amino and epoxy group. KH550-BN and KH560-Al2O3 were pre-assembled in toluene and filled into PP to prepare composites, which thermal conductivity increased with increasing pre-assembling time. The experimental results show that KH550-BN and KH560-Al2O3 do in-situ self-assemble in PP melt. The thermal conductivity of composites with in-situ self-assembling had 21.6% improvement than that of composites with no assembling. A low-cost, simple and efficient method for preparing thermally conductive and insulating composites is realized.

In this article, we report a robust strategy to prepare polymer composites with enhanced thermal conductivity and mechanical properties for geothermal heat pump pipes, in which high density polyethylene (HDPE) used as matrix, various inorganic fillers including zero-dimensional (0D) aluminium spherical particles (Al-SPs), one-dimensional (1D) carbon fibres (CF) and two-dimensional (2D) graphite platelets (GPs), used alone or blended as modifier. The as-prepared polymer composites are GPs/HDPE, GPs/CF/HDPE, GPs/Al-SPs/HDPE and GPs/CF/Al-SPs/HDPE. Thermal conductivity and mechanical properties of these polymer composites were characterised. The results indicate that of all these as-prepared polymer composites, GPs/CF/Al-SPs/HDPE composites are the only one which possesses preferable and comprehensive properties both in thermal conductivity and mechanical properties due to the synergistic effect of filler. The thermal conductivity, elongation at break and tensile strength of GPs/ CF/Al-SPs/HDPE composites prepared with GPs (9 wt%), CF (3 wt%) and Al-SPs (3 wt%) were 0.803 W m−1K−1, 70.6 % and 26.69 MPa, respectively, which could meet the commercial requirements of the geothermal heat pump pipes.

A high heat-resistant hydroxyl boron–silicone vinylidene oil (HBSVO) was synthesized by copolymerizing hydroxyl polyborosiloxane oil (HPBSO) prepolymer with fumaryl chloride. The temperature at 5% mass loss (T5), 10% mass loss (T10), and maximum decomposition rate (Tmax) of HBSVO was 515, 550, and 600 °C, respectively. The structure –Si–O–B–O–C(=O)–CH=CH–C(=O)– in the backbone of HBSVO might cause a tendency to form a five-member ring structure by hyperconjugation action between boron atom and vinylidene groups. The hyperconjugation action, which improved the heat-resistant and hydrolysis-resistant properties of HBSVO, was confirmed by UV spectroscopy, 11B-NMR, and 1H-NMR. The chemical moieties (–Si–O–B–O–C(=O)–CH=CH–C(=O)–) were also identified by Fourier transform infrared (FT-IR) and 29Si-NMR (CDCl3) spectroscopies.

In this paper, a simple thermal decomposition synthesis route for a carbon–nitrogen–sulfur (C–N–S) co-doped titanium dioxide (TiO2) mischcrystal with an isobandgap property for visible light applications using urea as the C, and N source and titanium(IV) sulfate [Ti(SO4)2] as S source is reported. The C–N–S co-doped TiO2 mischcrystal exhibited a unique isobandgap characteristic and prominent red-shift in the ultraviolet-visible absorption spectrum and a much narrower band gap (2.42 eV and 1.39 eV) because of defects and impurity levels which were confirmed using powder X-ray diffraction, diffuse reflectance spectroscopy (DRS), photoluminescence, Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). The excellent photocatalytic performance of the C–N–S co-doped TiO2 mischcrystal samples was demonstrated using degradation of methylene blue and phenol under visible light. The apparent degradation rate of black TiO2 is 4–7 times higher than that of C–N–S co-doped TiO2 (anatase or rutile) under visible light irradiation. The valence band XPS and DRS results were carefully examined to understand the band gap reduction of C–N–S co-doped TiO2. This study confirms that the band gap structure of C–N–S co-doped TiO2 is determined by the mixed crystalline structure and the formation of impurity levels and defective levels. A new idea is presented that will be useful for the design of band gap structure for photocatalysts with higher photocatalytic activities under visible light irradiation.

Water-encapsulated environment-friendly core–shell thermally expandable microspheres (TEMs) were prepared via inverse suspension polymerization under atmospheric pressure. Acrylonitrile (AN), methy...

Boron-containing phenyl silicone oil (BCPSO) with terminal boronic hydroxyl groups was synthesized by acid-catalyzed balance condensation polymerization using phenylboric acid, dimethyldichlorosilane and diphenyldichlorosilane as raw materials. The structure of BCPSO was characterized by 1H, 13C and 29Si nuclear magnetic resonance (NMR) and Fourier transform infrared spectrometry (FTIR). The thermal degradation behavior of BCPSO was tested by thermogravimetry-Fourier transform infrared spectrometry (TG-FTIR) analysis. The TG-FTIR results indicated that thermal decomposition of BCPSO had significant hysteresis over that of phenyl silicone oil. The empty electron orbital of boron atom could accept electron of peroxide free radical to generate conjugation effect at initial degradation stage of BCPSO, and this phenomenon was confirmed by 11B NMR, FTIR and Raman spectroscopies. As a result, temporarily stable intermediate was formed which increased the heat resistant of BCPSO.

The surface of alumina (Al2O3) particles was modified by a blocked isocyanate silane coupling agent, which was synthesized by using methylethyl ketoxime (MEKO) to block isocyanate-propyltriethoxy silane via nucleophilic reactions. For comparison, the surface of Al2O3 particles was also modified by propyltrimethoxy silane (KH-331). The thermally conductive and electrical insulating Al2O3/polyamide 6 composites were prepared by dispersing modified Al2O3 in polyamide 6 (PA6) using a twin-screw extruder. The X-ray photoelectron spectroscopy (XPS) results revealed that blocked isocyanate-propyltriethoxy silane and KH-331 were successfully attached to the surface of Al2O3 particles with chemical bonds. The blocked isocyanate silane modified Al2O3 were well dispersed in PA6 as revealed by scanning electron microscopy (SEM). When the Al2O3 content was 70 wt%, the tensile strength (85.2 MPa) and flexural strength (136.4 MPa) of blocked isocyanate silane modified Al2O3/PA6 composites were higher than those of KH-331 modified Al2O3/PA6 composites (52.5 MPa, 77.8 MPa), respectively. The thermal conductivity and impact strength of blocked isocyanate silane modified Al2O3/PA6 composites were also higher than that of KH-331 modified Al2O3/PA6 composites at the same content of Al2O3. The volume electrical resistivity of modified Al2O3/PA6 composites decreased with increasing Al2O3 content, but they still were good electrical insulating materials.

Thermally expandable microspheres (TEMs), employing PMMA as the shell and NaHCO3/ethanol as the core, were prepared via thermally induced phase separation (TIPS). The addition of NaHCO3 improves the foaming properties of the TEMs. A mechanism for TEMs formation was proposed, comprising the following steps: (1) the separation of homogeneous polymer solutions into polymer-rich and polymer-poor phases upon cooling, where decreases in both interfacial tension and interfacial free energy (ΔG) facilitate sphere formation in a polymer-rich phase located in the polymer-poor phase; (2) the deposition of PMMA and shell formation at the interface, aided by the acute contact angle (θ) and positive spreading coefficient (S); (3) the constant deposition of PMMA shells from both the polymer-rich phase and polymer-poor phase upon cooling; and (4) the detachment of TEMs from each other facilitated by shear force from stirring. This mechanism was supported by calculations, and the effects of quench rates and stirring speeds.

Li-doped TiO2/SO42− nanoparticles was successfully synthesized via a simple calcinination process in a vacuum environment using Ti(SO4)2 and LiBr as precursors, and were characterized by TEM, XRD, IR, DLS, XPS and UV-vis (DRS). Li doping can reduce the diameters of TiO2 nanoparticles and affect the surface chemical forms and structures. The as-prepared photocatalysts with different LiBr contents exhibited a notably enhanced degradation efficiency for methylene blue, and exhibited the highest photocatalytic activity under UV light when the molar doping ratio of Li was 0.0125. Moreover, the most photocatalytically efficient sample also showed much higher activity for eliminating methylene blue under visible light (380 < λ < 700 nm) by applying a negative bias than P25 and the control samples without applying a negative bias. The introduced negative bias electrostatic fields could not only render TiO2 responsive to visible light, but was also able to increase the lifetime of the photo-excited charges in the doped semiconductor. This provides a facile, fast and universal method to rapidly degrade organic materials based on the Franz–Keldysh effect and the synergetic effects of the electrostatic force.

SiO2 particles were modified by γ-aminopropyltriethoxy silane (KH550) and γ-(2,3-epoxypropoxy)propyltrimethoxy silane (KH560) in sequence to prepare SiO2 particles with silicone-methoxy groups on surface (SiO2-s-Si(OCH3)3). X-ray photoelectron spectroscopy (XPS) and thermal gravimetric analysis (TGA) were used to characterize the modified SiO2 particles. The SiO2-s-Si(OCH3)3 particles and tetramethoxysilane were used to co-cure hydroxyl silicone oil. The strong interfacial interactions between silicone rubber and fillers, which came from hydrolyzed SiO2-s-Si(OCH3)3 particles in situ reacting with hydroxyl silicone oil, had a great effect on the properties of composites. The mechanical properties, thermal conductivity, dielectric strength and volume resistivity of SiO2-s-Si(OCH3)3/silicone rubber composites were considerably higher than that of pristine SiO2/silicone rubber composites at the same content of SiO2, while the dielectric constant and dielectric loss tangent of SiO2-s-Si(OCH3)3/silicone rubber composites was lower than that of pristine SiO2/silicone rubber composites at the same content of SiO2.

In this article, we report a direct synthetic route to prepare P3HT/CdS nanocomposites with cadmium acetate dihydrate (Cd(OOCCH3)2.2H2O) used as the cadmium source, sulfur powder (S) as the sulfur source, dichlorobenzene (DCB) and dimethyl sulfoxide (DMSO) as cosolvents, phosphonic ester end-functionalized P3HT as a conjugated polymer template. The as-prepared P3HT/CdS nanocomposites were characterized by Fourier transform infrared (FTIR) spectroscopy, proton nuclear magnetic resonance (1H NMR) spectroscopy, X-ray diffraction (XRD) patterns, transmission electron microscope (TEM), ultraviolet-visible (UV-vis) and photoluminescence (PL) spectra. The results showed that the size and distribution of CdS nanocrystals were not only temperature-dependent, but also greatly influenced by the S/Cd molar ratio. CdS nanocrystals were dispersed uniformly in the P3HT/CdS nanocomposites, which indicated that end-functionalized P3HT could be used as a template to prevent CdS from aggregating effectively. The occurrence of charge transfer at the P3HT/ CdS interface was evident from UV-vis absorption and PL studies, which indicated that ionic bonding between CdS nanocrystals and phosphonic ester end-functionalized P3HT can promote the transfer of charge in P3HT/ CdS nanocomposites. Therefore, it is a promising method to simplify the procedure for large-scale synthesis of organic-inorganic nanocomposites used in solar cells with high photoelectric conversion efficiency.

This paper presented the preparation of ZnS-AgIn5S8/fluoropolymer fiber composites and their performance for H2 evolution from splitting of water under similar sunlight irradiation. The scanning electron microscopy (SEM) images showed that ZnS-AgIn5S8 particles were loaded on the fiber surface by hydrothermal synthesis. The average rate of H2 evolution of ZnS-AgIn5S8 powders slightly decreased, while the average rate of H2 evolution of ZnS-AgIn5S8/fluoropolymer fiber composites increased from the first to the third run. The average rate of H2 evolution using ZnS-AgIn5S8/fluoropolymer fiber composites as catalyst was 2.0 times higher than that of ZnS-AgIn5S8 powders in the third run.

This paper presented the preparation of Bi2S3–TiO2 heterojunction/polymer fiber composites and their performance of the degradation of methylene blue using Xe lamp irradiation. The polysulphone (PSU)/styrene-maleic anhydride copolymer (SMA) fibers were prepared by electrospinning. Bismuth ions were introduced onto the surface of polymer fiber by the coordinating of carboxyl of SMA, sulfide ions were incorporated to react with bismuth ions under hydrothermal condition. TiO2 was deposited on the surface of the Bi2S3 by the reaction of titanium ions with urea also under hydrothermal condition. Scanning electron microscopy (SEM) and high resolution transmission electron microscope (HRTEM) images revealed that Bi2S3–TiO2 heterojunction was uniformly distributed on the surface of PSU/SMA fibers. The ultraviolet–visible absorption spectra (UV/VIS) showed that the Bi2S3–TiO2 heterojunction/polymer fiber composites possess good visible-light response ability. The degradation rate of methylene blue in Bi2S3–TiO2 heterojunction/polymer fiber composites system was considerably higher than that of Degussa P25 or Bi2S3–TiO2 heterojunction system under Xe lamp irradiation.

The preparation and photocatalysis of TiO 2 –ZnS/fluoropolymer fiber composites were investigated. The fluoropolymer nanofiber mats with carboxyl groups were prepared by electrospinning, and then titanium and zinc ions were introduced onto the fiber surfaces by the coordinating of carboxyl of fluoropolymer in solution. The TiO 2 –ZnS composites with diameters 15 nm to 1 μm were immobilized on the surface of fluoropolymer electrospun fiber using hydrothermal synthesis. The Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy analysis reveal that some chemical interaction exists between TiO 2 –ZnS composites and fluoropolymer fibers, so the semiconductor composites were immobilized tightly on the surface of fluoropolymer fibers. The ultraviolet–visible absorption spectra show the TiO 2 –ZnS/fluoropolymer fiber composites have low band gap and good visible-light response ability. The degradation rate of methylene blue in TiO 2 –ZnS/fluoropolymer fiber composites system was considerably higher than that of TiO 2 or TiO 2 –ZnS nanoparticles system under visible-light irradiation, because the TiO 2 –ZnS/fluoropolymer fiber composites possess good visible-light response ability, high specific surface areas, and adsorption–migration–photodegradation process. The photocatalytic activity of TiO 2 –ZnS/fluoropolymer fiber composites changes indistinctively after 10 repeating photocatalysis tests.

This paper focuses on the preparation of ZnIn 2 S 4 /fluoropolymer fiber composites and their performance for H 2 evolution from splitting of water using Xe lamp irradiation. Hexafluorobutyl acrylate- co -methacrylic acid (poly(HFBA- co -MAA)) is synthesized by a solution polymerization. Next, the fluoropolymer fibers, which have around 100 nm in average diameter, of poly(HFBA- co -MAA) and polyvinylidene fluoride (PVDF) mixtures are obtained by electrospinning. Then, zinc and indium ions are introduced onto the fiber surface by coordinating with carboxyls of MAA. After that, sulfide ions are incorporated to react with zinc and indium ions by a hydrothermal synthesis. Thus, ZnIn 2 S 4 particles of around 800 nm in average size, are obtained and well loaded on the fiber surface. The absorption edge of ZnIn 2 S 4 /fluoropolymer fiber composites is at 510 nm within the visible-light region. Photocatalytic H 2 evolution from water was investigated using Xe lamp. It was found that the average rate of H 2 evolution of ZnIn 2 S 4 powders gradually decreased, while the average rate of H 2 evolution of ZnIn 2 S 4 /fluoropolymer fiber composites increased from the first to the third run. The average rate of H 2 evolution using the ZnIn 2 S 4 /fluoropolymer fiber composites as the catalyst achieved 9.1 mL/h in the third run.

The semiconductor–polymer nanocomposites were widely used in the high-tech field, such as membrane separation, photoelectric, and catalytic materials [1]. The fluoropolymer nanofiber is a kind of suitable carrier for catalyzing because of its high surface areas, weatherability, thermal, and radiate resistance for the protection of C–F bond around the main chain [2]. Thermal property of semiconductor–fluoropolymer nanocomposites is one of the most important parameters for its application as photoelectric or catalytic materials [3]. However, most studies focus on the preparation and functional performance of semiconductor– fluoropolymer nanocomposites [4], but few reports on its thermal property, especially the thermal property of semiconductor–fluoropolymer fiber nanocomposites which was prepared by loading methods in the past decades. In this communication we investigated the thermal property of TiO2–fluoropolymer fiber nanocomposites prepared by the blending and loading method. This work conform both the influencing factors of thermal stability and melting peak temperature of TiO2–fluoropolymer fiber nanocomposites in the preparation method and composites structure. Experimental method

The non-isothermal crystallization kinetics of polypropylene (PP), PP/anhydrite composites were investigated by differential scanning calorimetry (DSC) with various cooling rates. The Avrami analysis modified by Jeziorny and a method developed by Mo were employed to describe the non-isothermal crystallization process of these samples. The difference in the exponent n between PP and PP/anhydrite composites indicated that non-isothermal kinetic crystallization corresponded to tri-dimensional growth with heterogeneous nucleation. The values of half-time, Zc and F(T) showed that the crystallization rate increased with the increasing of cooling rates for PP and PP/anhydrite composites, but the crystallization rate of PP/anhydrite composites was faster than that of PP at a given cooling rate. The method developed by Ozawa did not describe the non-isothermal crystallization process of PP very well. Moreover, the method proposed by Kissinger was used to evaluate the activation energy of the mentioned samples. The result showed that the activation energy of PP/anhydrite was greatly larger than that of PP.

The ZnS particles were immobilized on the surface of poly(vinylidene difluoride) (PVDF) mixing methacrylic acid (MAA)-trifluoroethyl acrylate (TFA) copolymer electrospun nanofibers. The PVDF and MAATFA copolymer nanofibers were prepared by electrospinning. Zinc ions were introduced onto the surface of nanofibers by coordinating with the carboxyls of MAA, and then sulfide ions were added to react with zinc ions to form ZnS particles under hydrothermal condition. The size and the amount of ZnS particles increased with the reaction time prolonging. The Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) results reveal that a chemical interaction exists between ZnS and fluoropolymer fibers. The degradation rate of methylene blue in ZnS–fluoropolymer nanocomposite system was considerably higher than in that of ZnS powders system under UV irradiation. There may be an adsorption-migration-photodegradation process during the degradation of methylene blue by using ZnS–fluoropolymer nanocomposites as photocatalyst. The photocatalytic activity of ZnS–fluoropolymer nanocomposites changes indistinctively after 10 times repeating tests.

The preparation and photocatalytic properties of titanium dioxide (TiO 2 )–fluoropolymer fiber nanocomposites were studied. The fluoropolymer nanofibers with carboxyl group were prepared by electrospinning. The complex was formed between carboxyl on fluoropolymer electrospun fiber surface and titanium ion, and then the TiO 2 nanoparticles were immobilized on the surface of fluoropolymer electrospun fibers through hydrothermal complex-precipitation. By controlling the reaction conditions, different sizes and numbers of TiO 2 nanocrystals can be obtained. The Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) results reveal that an interaction exists between TiO 2 and fluoropolymer fibers. The degradation of methylene blue solution is performed by TiO 2 –fluoropolymer fiber nanocomposites under UV irradiation. There may be an adsorption–migration–photodegradation process during the degradation of methylene blue by using TiO 2 –fluoropolymer fiber nanocomposites as photocatalyst. The experimental results show that the TiO 2 –fluoropolymer fiber nanocomposites have good photocatalytic ability, recycling and stability for the potential applicability in an environmental remediation.

A new hyperdispersant agent with SiOH as an anchoring group and poly(butyl acrylate) as a solvatable chain was synthesized, and its effect on the properties of polypropylene (PP)/CaSO4 composites was investigated. Fourier transform infrared spectroscopy results showed that the hyperdispersant agent reacted on the CaSO4 surface and the modified CaSO4 particles. The tensile strength and impact strength of the PP/CaSO4 composites increased about 14 and 34%, respectively, versus that of PP/CaSO4 (filled with the same unmodified fraction). According to surface analysis by scanning electron microscopy, the CaSO4 particles were buried well in the PP matrix when CaSO4 was coated with the hyperdispersant agent. CaSO4 significantly increased the crystallization temperature and crystallization rate of PP by differential scanning calorimetry, but the addition of hyperdispersant-agent-modified CaSO4 did not lead to the formation of crystalline PP through X-ray diffraction. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

The carboxyl group-containing acrylic resin for powder coatings can be obtained by succinic anhydride reacting with hydroxyl group-containing acrylic resin, which was prepared by radical copolymerization of methyl methacrylate (MMA), n -butyl methacrylate (BMA) and β-hydroxypropyl methacrylate (HPMA) using 2,2′-azobisisobutyronitrile (AIBN) as initiator in toluene solution. The influence of synthesis method, weight ratio of monomers, and the amount of succinic anhydride on carboxyl group-containing acrylic resin was investigated. The 1 H NMR results reveal that carboxyl group was successfully attached to acrylic resins. The optimum monomer weight ratio is MMA:BMA:HPMA = 65:20:15. The acid value of resin increases with the increasing of the amount of succinic anhydride, while the T g of resin decreases.

This paper presents a new synthetic route to hybridize ZnS semiconductor nanoparticles and poly(vinyl alcohol) (PVA) based electrospinning nanofibers. At first, zinc ions are introduced onto the surface of carboxylic PVA nanofibers. Then sulfide ions are added to react with zinc ions to form ZnS nanoparticles. The average diameter of the nanofibers is about 300 nm, and the diameter of the ZnS nanoparticles is about 5 nm. The photoluminescence spectrum of ZnS/carboxylic PVA nanocomposites has a 60 nm blue shift compared with that of the corresponding bulk ZnS sample. The carboxylic PVA enhances the quantum effects of the ZnS nanoparticles.

Sn-doped CdS/TiO2 heterojunction was synthesized on the conducting polymer fiber mat by hydrothermal method. The conducting polymer fiber mat was made by electrospinning from polyvinylidene fluoride, styrene-maleic anhydride copolymer, and nano-graphites as conducting fillers. The Sn-doped CdS/TiO2 heterojunction was characterized by XRD, XPS, SEM, TEM, TGA, and UV–Vis absorption spectra. Under simulated solar light irradiation, a combination of Sn-doped CdS/TiO2/conducting polymer was found to be highly efficient for photocatalytic hydrogen evolution from splitting of water. The photocatalytic hydrogen production efficiency was up to 2885 μmol h−1 g−1cat. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42300.

It is difficult to prepare polyethylene/montmorillonite by direct melt mixing because of the difference in character between polyethylene and montmorillonite. Therefore, it is necessary to modify polyethylene with polar groups, which can increase the hydrophilicity of polyethylene. At the same time, the inorganic montmorillonite should be modified with long-chain alkyl ammonium to increase the basing space between the interlayers. Thus, through the grafting of the polar monomer onto the main chain of polyethylene by reactive extrusion, polyethylene/montmorillonite nanocomposites can be prepared by the melt mixing of the grafter and organic montmorillonite. Fourier transform infrared has been used to prove that the monomers are grafted onto polyethylene. X-ray diffraction and transmission electron microscopy have been employed to characterize the nanocomposites. Furthermore, thermogravimetric analysis measurements show that the thermal stability of the nanocomposites is improved in comparison with that of the virgin materials. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 805–809, 2006

The graft reaction of succinic anhydride onto poly(vinyl alcohol) (PVA) was catalyzed by p-toluenesulfonic acid monohydrate in solid state. The infrared spectra and 1H-NMR spectra confirmed that succinic anhydride was successfully grafted onto PVA backbone. The influences of reaction temperature, reaction time, the amount of succinic anhydride, and the amount of catalyst on the graft reaction were studied. Uncrosslinked PVA graft copolymer with grafting degree up to about 6.5% could be obtained under low reaction temperature, short reaction time, and low amount of catalyst, whereas crosslinked PVA with high gel content could be obtained under high reaction temperature, long reaction time, and high amount of catalyst. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 848–852, 2007

Reactivity of acrylonitrile-butadiene-styrene terpolymer (ABS) grafted with long-chain carboxylic acids, such as undecylenic acid and oleic acid, was investigated and compared with that of ABS grafted with short-chain carboxylic acids by reacting with dodecylamine, glycidyl methacrylate (GMA), and 2-ethyl-2-oxazoline in solution, and with polyamide (PA) in melt. The overall activation energy of ABS-g-acrylic acid, ABS-g-crotonic acid, ABS-g-undecylenic acid and ABS-g-oleic acid reacting with dodecylamine was 31.2, 16.2, 18.2 and 21.6 kJ/mol, respectively. The overall activation energy of ABS-g-acrylic acid, ABS-g-crotonic acid, ABS-g-undecylenic acid and ABS-g-oleic acid reacting with GMA was 29.0, 31.9, 61.4 and 61.8 kJ/mol, respectively. The stronger the acidity of grafted acid, the higher the percentage of the grafted acid reacted. The overall activation energy of ABS-g-acrylic acid, ABS-g-crotonic acid, ABS-g-undecylenic acid and ABS-g-oleic acid reacting with 2-ethyl-2-oxazoline was 19.5, 20.9, 23.4 and 24.5 kJ/mol, respectively. The lower the steric hindrance and the higher the chain mobility of grafted acid, the higher the percentage of the grafted acid reacted. The reactivity of dodecylamine, GMA and 2-ethyl-2-oxazoline reacting with grafted ABS is: GMA

The Flory's gelation theory, non-equilibrium thermodynamic fluctuation theory and Avrami equation have been used to predict the gel time tg and the cure behavior of epoxy resin/organo-montmorillonite/diethylenetriamine intercalated nanocomposites at various temperatures and organo-montmorillonite loadings. The theoretical prediction is in good agreement with the experimental results obtained by dynamic torsional vibration method, and the results show that the addition of organo-montmorillonite reduces the gelation time tgand increases the rate of curing reaction, the value of k, and half-time of cure after gelation point t1/2 decreases with the increasing of cure temperature, and the value of n is ~2 at the lower temperatures (

Polyvinyl chloride (PVC)/organic-montmorillonite composites were prepared by melt intercalation. Their structures and properties were investigated with X-ray diffraction (XRD), differential scanning calorimetry (DSC) and mechanical testing. The results showed that PVC chains could be intercalated into the gallery of organically modified montmorillonite to form exfoliated PVC/organic-montmorillonite nanocomposites, and the glass transition temperatures of PVC/organic-montmorillonite composites were lower than that of neat PVC. However, the tensile strength, and both the Izod type and Charpy notched impact strengths of PVC/organic-montmorillonite nanocomposites were fitted with the linear expressions: t=535.07-6.39Tg, sI=378.76-4.59Tg and sC=276.29-3.59Tg, respectively.

The non-isothermal crystallization kinetics of polyethylene (PE), PE/organic-montmorillonite (Org-MMT) composites were investigated by differential scanning calorimetry (DSC) with various cooling rates. The Avrami analysis modified by Jeziorny and a method developed by Mo were employed to describe the non-isothermal crystallization process of these samples very well. The difference in the exponent n between PE and PE/Org-MMT nanocomposites, indicated that non-isothermal kinetic crystallization corresponded to tridimensional growth with heterogeneous nucleation. The values of half-time, Zc and F(T) showed that the crystallization rate increased with the increasing of cooling rates for PE and PE/Org-MMT composites, but the crystallization rate of PE/Org-MMT composite was faster than that of PE at a given cooling rate. The method developed by Ozawa did not describe the non-isothermal crystallization process of PE very well. Moreover, the method proposed by Kissinger was used to evaluate the activation energy of the mentioned samples. The results showed that the activation energy of PE/Org-MMT was greatly larger than that of PE.

A water-soluble and low stimulation sodium bisulfite blocked isophorone diisocyanate (IPDI) has been prepared. The blocking and deblocking of the blocked IPDI is observed by hot-stage Fourier transform infrared (FTIR) spectrophotometer. The experimental results reveal that IPDI is successfully blocked by sodium bisulfite and the blocked IPDI can regenerate isocyanate groups when the temperature is higher than 80°C. Differential scanning calorimetry analysis indicates that blocked IPDI deblocks initially at around 85°C and reaches the maximum deblocking rate at 117°C. The blocked IPDI in liquid and solid states are stable after being stored for 12 months at room temperature. The blocked IPDI is used as curing agent for waterborne hydroxyl polyurethane, which has good adhesive performance and long pot life. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

In this article, we report a facile, direct synthesis route to prepare CdSe/P3HT nanocomposites with CdO used as cadmium source, Se powder as selenium source, liquid paraffin and oleic acid as solvents, P3HT as a conjugated polymer template. The effect of the reaction temperature as well as the Cd:Se molar ratio on the morphology and photovoltaic property of CdSe/P3HT nanocomposites was studied. The results show that the shape and the degree of aggregation of CdSe nanocrystals are not only temperature-dependent, but also heavily influenced by the Cd:Se ratio, changing from dot-shaped to tetrapod-shaped, and from homo-dispersed to seriously aggregative. The UV–vis absorption spectra of CdSe-P3HT show a broader range and higher intensity of absorption than that of pure P3HT. The improved PL quenching in PL spectra of CdSe-P3HT indicates charge transfer between CdSe nanocrystals and P3HT.

The low bandgap 3-hexylthiophene/pyridine copolymers (P3HT/PY) were synthesized and the composites of P3HT/PY and CdSe QDs were prepared. The characterization are performed with 1H NMR, UV-vis, PL, TEM, XPS and cyclic voltammetry (CV). The results show that the P3HT/PY copolymers have an electrochemical bandgap of 1.67 eV, while the composites show a broader absorption and a lower bandgap than the copolymers. The highly efficient fluorescence quenching of the composites indicates that the ultrafast charge transfer happened between the P3HT/PY copolymers and the CdSe QDs. The composites show a uniform dispersion and good compatibility, and the surface chemistry study verified the chemical bonding between them. In addition, both the copolymers and the composites exhibited p- and n-type doping ability, and the P3HT/PY/CdSe composites have a better donor-acceptor match, which is a promising p-n type semiconductor material.