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This study presents the improvement in flame retardancy of wood polymer composites (WPCs) by boron phosphate (BPO4) additive. The WPCs were manufactured by phenol formaldehyde and wood flour of Oriental beech (Fagus orientalis L.) using compression molding. Polydiphenylmethane-4,4’-diisocyanate (PMDI) was also added to enhance the compatibility of hydrophilic wood flour and hydrophobic polymer resin. The strengthening of interfacial adhesion by PMDI incorporation resulted in better mechanical (flexural) and physical (water absorption, thickness swelling) properties. The BPO4 flame-retardant additive in WPCs formulation was first reported and thermal behaviors of composites were investigated by thermogravimetric analysis (TGA), limiting oxygen index (LOI) and UL-94 tests. The BPO4 compound promoted the char formation of WPCs, and the LOI values of composites were increased from 28.7 to 35.6. The UL-94 tests also showed that the flame retardancy of composites were improved by changing the V-2 rating to V-0 with the addition of 5 wt.% BPO4.

Background: The effects of nanosized boron phosphate-filled sodium alginate composite gel (SA/BP) on the biological characteristics of three types of glioblastoma multiforme (GBM) cells (C6, U87MG and T98G) were examined in this study. MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assay was used to determine the cytotoxicity of the composite gel on GBM, which was then compared to L929 healthy cells. Furthermore, wound healing, apoptosis, and colony formation capacities were evaluated. The investigation revealed that the SA/BP composite gel was successful in all GBM cells and could be used as a treatment agent for GBM and/or other invasive cancer types. Methods and results: According to the results, the SA/BP composite gel had no effect on healthy fibroblast cells but had a lethal effect on all glioblastoma cells. Additionally, the wound healing method was used to examine the effect of the SA/BP composite gel on cell migration. It was discovered that the wound closed in 24 h in untreated control group cells, while the SA/BP composite gel closed up to 29.62%, 26.77% and 11.31% of the wound for C6, U87MG and T98G cell lines respectively. SA/BP significantly reduced cell migration in cancer cells. The effect of the generated SA/BP composite gel on cell colony development was assessed using a colony formation assay, and the cells reduced colony formation for all GBMs. It was roughly 45% for 24 h and 30% for 48 h when compared to the control group for C6 cells, 33%(24 h) and 40%(48 h) for U87MG cells, 40%(24 h) and 43%(48 h) for T98G cells. DAPI(4′,6-Diamidino-2-phenylindole) and JC-1(5,5′,6,6′-Tetrachloro-1,1′,3,3′-tetraethylbenzimidazolylcarbocyanine, iodide) staining to evaluate apoptosis revealed that the SA/BP composite gel dramatically enhanced the frequency of all GBMs undergoing apoptosis. Conclusions: In line with experimental findings, it was observed that the SA/BP composite gel system did not affect healthy fibroblast cells but had a cytotoxic effect on glioblastoma cells, significantly reduced cell migration and colony-forming capacity of cells, and significantly increased apoptosis and depolarization of cell membranes. Based on all these findings, it can be said that SA/BP composite gel has cytotoxic, antiproliferative and antiapoptotic effects on different glioblastoma cells. [ABSTRACT FROM AUTHOR]

Mesoporous NiMoAl catalysts with boron phosphate (BPO4) modification were synthesized through the complete liquid-phase method. X-ray diffraction (XRD) analysis evidenced the presence of BPO4-AlOOH mixed support in these BPO4-modified NiMoAl samples. The total amount of acid sites declined, but the surface acidity was strengthened by adding BPO4 into the NiMoAl catalyst. It's worth noting that the incorporation of BPO4 could increase the concentrations of Ni and Mo species on the catalyst surface and greatly improve the dispersion of (Ni)MoS2 active phases, as indicated by X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) measurements. The catalytic performance of these BPO4-modified NiMoAl catalysts was investigated with the hydroprocessing of fluid catalytic cracking (FCC) slurry oil. The nitrogen-containing compounds removal from the oil was significantly enhanced with increasing the molar ratio of boron phosphate/aluminum. The NM-BPA(0.55) catalyst exhibited the best hydrodenitrogenation (HDN) activity, highlighting the significant impact of Mo sulfidation degree and the dispersion of active metals on HDN performance. The introduction of boron phosphate could also promote the hydrocracking activity of the NiMoAl catalyst, as demonstrated by SARA analysis and simulated distillation of liquid products.

In this study, the effects of the nanoscaled boron phosphate (BP) addition to polypyrrole (PPy) were investigated. Firstly, the composites containing different weight ratios of BP were prepared and characterized using Fourier-Transform Infrared-attenuated total reflection (FTIR-ATR), UV-vis, X-ray diffraction (XRD), and scanning electron microscopy analyzes. FTIR-ATR analyzes indicated the electrostatic interactions between PPy and BP molecules whereas UV-vis analyzes showed that charge carrier concentration increased with the addition of BP. The electrical conductivity measurements indicated that the electrical conductivity of the pristine PPy increased from 11.1 Scm−1 to 160.6 Scm−1 with the addition of 20% BP by weight. Furthermore, with the addition of 20% BP, the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•) scavenging activity of PPy was significantly increased from 30.59 ± 0.5% to 49.18 ± 1.17% while 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical (ABTS•+) scavenging activity improved from 21.97 ± 1.07% to 29.70 ± 0.04%. The observed data have shown that electrically conductive PPy/BP nanocomposites can be a promising component for antioxidant materials. [ABSTRACT FROM AUTHOR]

The recent studies focused on the blend membranes to a great extent due to their capability of gathering some important polymer characteristic features. In this survey, boron phosphate (BP) doped sulfonated poly (ether ether ketone)/Poly (vinylidene fluoride) (SPEEK/PVDF) blend membrane having high ionic conduction capability was synthesized. The boron phosphate doping to the membrane matrix enhanced the membrane properties in terms of proton exchange membrane conditions. The sol-gel and casting method was used to synthesise the SPEEK/PVDF blend membrane. The characterization tests to observe the structure of the membrane, such as X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), FT-IR and mechanical/thermal stability tests were conducted. The membrane ionic transportation and water retention were improved directly by the addition of boron phosphate. The highest power density (242 mW cm−2) and current density (400 mA cm−2) at 0.6 V were obtained by SPEEK/PVDF/10BP, respectively. Additionally, the proton conductivity value of 39 mS cm−1 was obtained for SPEEK/PVDF/10BP sample at 80 °C. The authors concluded that both boron phosphate additive and SPEEK/PVDF blend membrane have promising results for fuel cell future operations. [Display omitted] • SPEEK/PVDF membranes have great PEM fuel cell performance by boron phosphate addition. • Boron phosphate addition enhances the proton conductivity of the SPEEK/PVDF blend membranes. • The boron phosphate addition increases the mechanic stability of SPEEK/PVDF blend membrane. [ABSTRACT FROM AUTHOR]

The aim of this work was to improve the smoke‐suppression performance and flame‐retardant effect of a phosphorus‐based bifunctional flame retardant (PDEP)/expandable graphite (EG) binary flame‐retardant system by incorporating two boron‐containing inorganic compounds, zinc borate and boron phosphate (BP), into rigid polyurethane foams (RPUFs). The results revealed that both the boron‐containing inorganic compounds inhibited smoke/heat release of retardant RPUF by accelerating the crosslinking and char forming of the material to promote phosphorus retention in the solid phase. In particular, when 2% BP replaced the same amount of PDEP, the total smoke release value of the RPUF/2%BP/10%PDEP/8%EG (2B10P8E) sample decreased by 30.0% compared with the RPUF/12%PDEP/8%EG (12P8E) sample. This lifted smoke‐suppressive performance mainly due to the existence of Brønsted and Lewis acid sites on BP, which can accelerate the dehydration and crosslinking of hydroxyl in compounds, thus resulting in more phosphorus‐oxygen components retained in the condensed phase, effectively inhibiting the smoke/heat release of the composites. The addition of BP balanced the bi‐phase flame‐retardant effects of RPUF systems containing phosphorus‐based flame retardant due to a strong catalytically charring effect. Thus, the flame‐retardant efficiency was also greatly improved. The smoke‐suppressive and flame‐retardant modes of action of the ternary system was evaluated by experiments using TGA Fourier transform infrared spectroscopy, SEM, energy dispersive spectrometry, pyrolysis‐gas chromatography/mass spectrometry and Fourier transform infrared spectroscopy. © 2022 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

The composite flame retardant was prepared by adding different proportions of synergist boron phosphate (BP) to the intumescent flame retardant (IFR). The composite flame retardant was added to polypropylene (PP) to prepare flame retardant PP composites. PP composites were characterized by vertical combustion, limiting oxygen index test, cone calorimeter test, thermogravimetric analysis and mechanical properties test. The results show that BP has significant synergistic flame retardant effect on IFR. When 2% BP and 13% IFR are added, PP/IFR/BP composite (sample 4#) has the best flame retardancy, the combustion grade reaches V-0, and the limiting oxygen index reaches 30.8%. The peak heat release rate, average heat release rate, total smoke production and total heat release of sample 4# are 19.51%, 4.40%, 34.00% and 6.87% lower than those of flame retardant PP with 15% IFR, respectively. The mass retention rate of sample 4# is increased by 50% at 700 °C. During the combustion process, the boron element of PP/IFR/BP composites catalyzes the crosslinking of IFR into carbon in the condensed phase. Compared with the composites without BP, the PP/IFR/BP carbon layer has a higher degree of expansion and is denser. The addition of BP synergist reduces the amount of flame retardant and significantly improves the mechanical properties of the composites. [ABSTRACT FROM AUTHOR]

The method of synthesis of a monophase boron phosphate (BPO4) powder has been refined. Single crystals of BPO4 free from solvent inclusions and cracks have been obtained by the top‐seeded solution growth technique with the seed orientation [010]. The growth is carried out under conditions of a low axial temperature gradient in the melt‐solution, which is varied in the range of 1–4°C cm−1. The value of the temperature gradient that promotes the growth of defective crystals is determined. The absorption spectra and optical homogeneity of crystals are studied. The chemical composition of polycrystalline BPO4 is studied using inductively coupled plasma mass spectrometry. The purity of the synthesized powder is better than 4 N. [ABSTRACT FROM AUTHOR]

SiO2-supported BPO4 catalysts have been prepared via a convenient one-pot process, characterized by XRD, N2 adsorption/desorption, FTIR, and NH3-TPD and investigated in the production of salicylonitrile using methyl salicylate and ammonia as the raw material in a vapor-phase fixed bed process. The results indicated that supporting BPO4 in SiO2 could increase the surface area and the amount of the moderate-to-strong acidic sites on surface, which markedly improved the catalytic performance. The effects of various reaction conditions, the effects of compositions on the catalytic activity, and the stability of the process have been studied in detail. Under the optimized conditions, an excellent 91.6% yield of salicylonitrile could be obtained, and good stability for the process was observed. The present study would provide foundation for industrial production of salicylonitrile. SiO2-supported BPO4 catalysts have been prepared via a convenient one-pot process, providing an excellent 91.6% yield of salicylonitrile using methyl salicylate and ammonia as the raw material in a vapor-phase fixed bed process. The result indicated that supporting BPO4 in SiO2 could increase the surface area and the amount of the moderate-to-strong acidic sites on surface, which markedly improved the catalytic performance. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Oxidative dehydrogenation of ethylbenzene is considered as an alternative route to styrene because of its exothermic and irreversible reaction nature, but encounters low styrene selectivity due to the deep‐oxidation over metal oxide‐based catalysts. Herein, we reported that a metal‐free boron‐based catalyst consisting of boron phosphate and boron nitride (BPO4/BN) exhibited high activity and selectivity in oxidative dehydrogenation of ethylbenzene to styrene. High selectivity of styrene (95.1%) was achieved at 27.7% ethylbenzene conversion level over the optimized BPO4/BN catalyst. The tetra‐coordinated boron (BO4) species of BPO4 was speculated to be responsible for the ODH of ethylbenzene, and a synergistic effect between BPO4 and BN can remarkably improve the catalytic performance of the BPO4/BN catalyst. The optimized BPO4/BN catalyst showed a higher styrene formation rate of 4.0 mmol gcat−1·h−1, compared individually to BPO4 (2.8 mmol·gcat–1·h–1) and BN (0.5 mmol·gcat–1·h–1). [ABSTRACT FROM AUTHOR]

New types of metal–organic framework based hybrid materials are designed and prepared, which involving the hybridization of various content of boron phosphate (BPO4) with the precursor of HKUST‐1. The structure of obtained HKUST‐1/BPO4 hybrid materials (HB) is fully investigated, and then applied to construct sulfonated poly (ether ether ketone) (SPEEK) based proton exchange membranes (SPEEK/HB). Owing to effective interactions between hybrid materials and SPEEK matrix, the achieved composite membranes reflect a considerable improvement in mechanical and thermal stability, oxidative stability, methanol permeation, and proton conductivity. In particular, the tensile strength of SPEEK/HB‐20 composite membrane is 41.3 MPa, which is 1.5 times higher than pristine SPEEK, and the methanol permeability reduced to one‐third of SPEEK at the same time. The SPEEK/HB‐10 displays the highest proton conductivity of 37.4 mS cm−1 at 80 °C, which is obviously higher than pristine SPEEK. These results reveal that the hybridization of HKUST‐1 with BPO4 provide a promising candidate in the modification of proton exchange membranes (PEMs), and this strategy also possess great application potential in other types of MOFs‐based hybrid materials. [ABSTRACT FROM AUTHOR]

In the present study, thermoelectric properties of composites formed by poly (3,4-ethylenedioxy thiophene):poly (styrene-4-sulfonate) (PEDOT:PSS)/boron phosphate (BPO4) were studied. First, BPO4 was synthesized at 1000°C using boric acid and phosphoric acid as precursors. Later, PEDOT:PSS was synthesized by oxidative chemical polymerization reaction at room temperature. Their composites were prepared in different mass ratios by ultrasonic homogenization. The composites were characterized using ultraviolet–visible (UV–vis.), attenuated total reflection accessory attached Fourier transform infrared (FTIR-ATR) spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy/energy dispersive X-ray analyzer (SEM–EDX). The power factor of the sample was obtained using the electrical conductivity and Seebeck coefficient measurements. The positive sign of Seebeck coefficient of the pristine PEDOT:PSS turned to the negative, which is the characteristic of n-type material, by addition of BPO4. The power factor of PEDOT:PSS was increased from 0.03 μWm−1 K−2 to 252 μWm−1 K−2 for the composite containing 25% BPO4 by weight. This indicates that BPO4 can be a good additive to prepare n-type TE material. [ABSTRACT FROM AUTHOR]

Utilizing renewable resources and accelerating thermal stabilization have been two main effective technical means to reduce the cost of poly(acrylonitrile) (PAN) based carbon fibre (CF). In this work, cross-linked poplar lignin (CPPL) with higher carbon content and 15 times the weight-average molecular weight of poplar lignin (PPL) was formed by doping boron phosphate (BP) in situ composites, which was blended with poly(acrylonitrile-co-vinyl acetate) (PANVA) to prepare a low-cost partially bio-based composite PANVA/CPPL-BP. During thermal stabilization, the C1s curve-fitting of x-ray photoelectron spectroscopy (XPS) spectra showed that the conjugated ladder structure of PANVA/CPPL-BP started to form at 230 °C, which was 20 °C lower than PANVA. And the acceleration in forming conjugated ladder structures was further confirmed by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric (TG), and TG-FTIR. During simulated low-temperature carbonization for composites stabilized at 230 °C in advance, the addition of CPPL-BP greatly improved the order of graphitic structure for PANVA. The mechanical property of CF mats has also been obviously improved by CPPL-BP. The possible mechanism that CPPL-BP accelerating the formation of conjugated ladder structures for PANVA/CPPL-BP during thermal stabilization was proposed. With such improvement on accelerating thermal stabilization and utilizing cheap bio-material at the same time, this PANVA/CPPL-BP composite has a great potential in developing low-cost CF.

The aim of this work was to investigate the catalysis of boron phosphate (BP) on the thermal stability and char forming in flame-retardant polyurethane-polyisocyanurate foams (FPUR-PIR) with dimethylmethylphosphonate (DMMP) and tris(2-chloropropyl) phosphate (TCPP). The flame-retardant performance and thermal stability of FPUR-PIR were evaluated by cone calorimetry (CONE), thermogravimetric analysis (TG) and microscale combustion calorimetry (MCC). Gas-phase products of FPUR-PIR during the thermal decomposition were investigated via thermogravimetric analyzer coupled with FTIR and mass spectrometry (TG-FTIR-MS). Elemental composition and content of the charred layer in detail were analyzed by X-ray photoelectron spectroscopy (XPS). It was observed that the incorporation of 3 mass% BP in FPUR-PIR decreases the heat release rate, total smoke released and CO production. Meanwhile, the addition of 3 mass% BP advances the release of gaseous products and lower the production of smoke and toxic products like -NCO compounds, PO* and cyanic acid in the gas phase. It can accelerate the dehydration of hydroxyl compounds and promote the char formation of -NCO compounds. This can improve the thermal and oxidation resistance of condensed phase. The catalytic behavior of the dehydration and char formation of BP in the thermal degradation of FPUR-PIR is attributed to Brønsted and Lewis acidic sites on BP. [ABSTRACT FROM AUTHOR]

Development of inexpensive, easily prepared, non-toxic, and efficient catalysts for the cycloaddition of CO2 with epoxides to synthesize five-membered cyclic carbonates is a very attractive topic in the field of CO2 transformation. In this work, we conducted the first work on the cycloaddition of CO2 with epoxides to produce cyclic carbonates catalyzed by a binary catalyst system consisting of KI and boron phosphate (BPO4), which are both inexpensive and non-toxic, and various corresponding cyclic carbonates could be produced with high yields (93-99 %) at 110 °C with a CO2 pressure of 4 MPa under solvent-free conditions. In the BPO4/KI catalyst system, BPO4, a Brønsted and Lewis acid hybrid, played the role of activating the epoxy ring through the formation of hydrogen bonds with Brønsted acidic sites and the interaction with Lewis acidic sites simultaneously, and thus enhanced the activity of KI for the cycloaddition of CO2 with epoxides significantly. Additionally, the activity of the BPO4/KI catalyst system showed no noticeable decrease after being reused five times, indicating that the BPO4 was stable under the reaction conditions. [ABSTRACT FROM AUTHOR]

Development of inexpensive, easily prepared, non-toxic, and efficient catalysts for the cycloaddition of CO2 with epoxides to synthesize five-membered cyclic carbonates is a very attractive topic in the field of CO2 transformation. In this work, we conducted the first work on the cycloaddition of CO2 with epoxides to produce cyclic carbonates catalyzed by a binary catalyst system consisting of KI and boron phosphate (BPO4), which are both inexpensive and non-toxic, and various corresponding cyclic carbonates could be produced with high yields (93-99 %) at 110 °C with a CO2 pressure of 4 MPa under solvent-free conditions. In the BPO4/KI catalyst system, BPO4, a Brønsted and Lewis acid hybrid, played the role of activating the epoxy ring through the formation of hydrogen bonds with Brønsted acidic sites and the interaction with Lewis acidic sites simultaneously, and thus enhanced the activity of KI for the cycloaddition of CO2 with epoxides significantly. Additionally, the activity of the BPO4/KI catalyst system showed no noticeable decrease after being reused five times, indicating that the BPO4 was stable under the reaction conditions. [ABSTRACT FROM AUTHOR]

Proton conductors capable of operating in a high temperature range (over 200 °C) have received great interest for proton exchange membrane fuel cells (PEMFCs). Here, we report promising candidates for inorganic composite membranes for PEMFCs using solid CeP 2 O 7 /BPO 4 and CeP 2 O 7 /BPO 4 /GO (without a liquid phase) at temperatures between 200 °C and 300 °C. BPO 4 is prepared by combining a B 3 PO 4 solution with an 85% H 3 PO 4 solution, and it is loaded with CeP 2 O 7 . Furthermore, graphite oxide (GO) is incorporated with the CeP 2 O 7 /BPO 4 -based composite materials to improve the proton conductivity. The structure and phase stability of the membranes are analysed by X-ray diffraction, Fourier transform infrared (FTIR) and thermos-gravimetric analysis (TGA), and the microstructure morphology is analysed by scanning electron microscopy (SEM). The CeP 2 O 7 /BPO 4 and CeP 2 O 7 /BPO 4 /GO composite electrolytes exhibit the high proton conductivities of 0.12 S cm −1 and 0.14 S cm −1 at 250 °C, respectively. Moreover, the peak power densities of the CeP 2 O 7 /BPO 4 /GO membrane are 149 mW cm −2 at 200 °C, 240 mW cm −2 at 250 °C and 184 mW cm −2 at 300 °C. [ABSTRACT FROM AUTHOR]

Remarkable progress has been made on the use of polymer electrolyte membranes (PEMs) for renewable-energy-related research. In particular, carbon nanotubes (CNTs) have emerged as versatile nanomaterials to modify PEMs. However, the inert ionic conduction ability and possible short-circuiting risk are the two major obstacles to their further development. In this work, CNTs are firstly functionalized with an inorganic proton conductor, boron phosphate (BPO 4 ), using a facile polydopamine-assisted sol-gel method to yield BPO 4 @CNTs. This new additive is then used to modify sulfonated poly(ether ether ketone) (SPEEK). Polydopamine coating layer can act as an extraordinary glue to homogeneously adhere BPO 4 nanoparticles on CNTs, thereby not only reducing the risk of short-circuiting, but also fabricating new proton-conducting pathways in the composite membranes. A comprehensive characterization reveals that the thermal stability, tensile properties, and dimensional stability of PEMs are significantly improved. Compared with pure SPEEK, the proton conductivity of SPEEK/BPO 4 @CNTs-2 is improved by 45% and 150% at 20 °C and at 80 °C, respectively. Furthermore, the H 2 /O 2 cell performance of SPEEK/BPO 4 @CNTs-2 membrane exhibits a peak power density of 340.7 mW cm −2 at 70 °C, which is significantly better than that of pure SPEEK (254.2 mW cm −2 ), demonstrating the great potential of proton conductors-functionalized CNTs in PEMs. [ABSTRACT FROM AUTHOR]

The solidification of radioactive borate waste (BW), which contains a high concentration of boron ions using cement waste forms is challenging because soluble borate hinders the cement hydration reaction. Here, BW was immobilized using a phosphate-based geopolymer, and the phase change of BW in the geopolymer was investigated. The geopolymers could solidify BW up to 50 wt% depending on the water content and heat curing conditions. In geopolymers cured at high temperatures (60 and 90 °C), the 7-day compressive strength increased as the BW waste loading increased up to 40 wt%. Heat curing promoted geopolymerization and the precipitation of amorphous boron phosphate, leading to an increase in the compressive strength. The formation of a new amorphous boron phosphate phase was confirmed by performing XRD, MAS NMR, and SEM analyses of the geopolymers and reaction products. These results can improve our understanding of the immobilization mechanism of BW in phosphate-based geopolymers. [Display omitted] • Phosphate-based geopolymers can immobilize borate waste up to 50 wt%. • Amorphous boron phosphate is formed along with the geopolymer binder. • 7-day compressive strength of geopolymer is proportional to borate waste loading. • Amorphous boron phosphate contributes to the enhancement in compressive strength. [ABSTRACT FROM AUTHOR]

In this work, europium ion was doped into boron phosphate nanoparticles (BPO 4) using an ultrasonic method followed by the calcination process. The nanoparticles were characterized by various techniques such as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), photoluminescence spectroscopy, transmission electron microscopy (TEM), and Fourier-transform infrared spectroscopy (FT-IR), Raman spectroscopy, and scanning electron microscopy (SEM). Doping of europium ion into the BPO 4 host crystal was proved by cell volume calculation from XRD patterns, the shift in Raman spectra, and photoluminescence properties. In addition, the europium doped boron phosphate (BPE) as a fluorescence sensor for the quantification of Zn2+ cation was studied. The obtained results showed the enhancement and shift of the photoluminescence peak from 292 to 340 nm. The sensor's selectivity toward this ion was verified in the presence of a variety of common interfering cations. Surprisingly, BPE revealed excellent selectivity and sensitivity towards Zn2+ in the presence of Pb2+, Na+, Fe2+, Al3+, Ca2+, Mg2+, Cu2+, Co2+, Ni2+, Mn2+, Cd2+, Hg2+, Ba2+ and Fe3+ cations. The fluorescence response was linearly proportional to the Zn2+concentration. After the addition of trace amounts of Zn2+ ions into the aqueous solution, a significant enhancement of fluorescence emission occurred with the detection limit of 0.3 μM. [Display omitted] • Europium ion was doped into boron phosphate nanoparticles. • A fluorescent sensor for the detection of Zn2+ ion. • The selectivity of the sensor toward this ion was verified. • Verification of ultrasound time and temperature on the sensor performance. [ABSTRACT FROM AUTHOR]

The intention of this work is to develop a heterogeneously catalyzed, environmentally friendly and sustainable process for the production of isosorbide by dehydration of sorbitol. The presence of the heterogeneous catalyst BP in the batch reactor had a great influence on the reaction rate. Trivalent B-, Al-, Fe-, Ce- and La-phosphates catalysts (MeP), as well as quadrivalent Zr-phosphates (ZrP-1 and ZrP-2) were studied in liquid-phase using autoclave reactors under autogenous pressure at different temperatures between 150 and 250 °C for different reaction times between 0.5 and 24 h. The catalytic activity depends on the acidity of the catalysts, as NH 3 -TPD technique revealed, on the surface area and the pore diameter determined by N 2 adsorption. Depending on the pH of the reaction medium, water molecules play a significant role in the reaction. A tremendous effect was observed when 100 wt.% sorbitol powder was used instead of aqueous 70 wt.% sorbitol solution as starting material. [ABSTRACT FROM AUTHOR]

A series of boron phosphate (BPO) modified ion-exchanged CsX zeolites, prepared by impregnation method, were characterized by a variety of means and utilized as catalysts for the side-chain alkylation of toluene with methanol. Both BPO and Cs species are highly dispersed on the surface/channel of the BPO/CsX zeolites. The addition of a small amount of BPO has no obvious effect on the basic strength of catalysts, but decreases the number of basic sites slightly. Meanwhile, more weak Lewis acidic sites appear with the increasing BPO loading. Compared with CsX, the BPO modified CsX catalysts exhibit lower ability for the adsorption/activation of methanol to produce surface intermediates like formaldehyde, unidentate formate and bidentate formate. Catalytic reaction results showed that modification of CsX with boron phosphate can improve both the conversion of toluene and the selectivity of styrene. The inhibition role in producing the unfavorable bidentate formate might be a key factor for finally resulting in the improvement of the catalytic properties of BPO/CsX catalysts for the side-chain alkylation of toluene with methanol. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the acid catalysis of boron phosphate (BP) to model compound dipentaerythritol (DPER) which acted as char source during the thermal degradation and combustion. Various amounts of BP were added in DPER and then the thermal degradation and combustion behaviors were studied by means of thermogravimetric analysis (TGA) and microscale combustion calorimeter (MCC). Evolved Gases were evaluated using TGA-FTIR; solid residues were fully characterized by FTIR, X-ray photoelectron spectroscopy (XPS), Raman analysis and scanning electron microscopy (SEM). The results of TGA and MCC showed that the addition of BP leaded to the earlier thermal degradation of DPER and increased the amount of char residues, significantly decreased the peak heat release rate of DPER; the results of TGA-FTIR, XPS, Raman analysis and SEM revealed that the presence of BP accelerated the dehydration of DPER, kept more carbon and oxygen elements in condensed phases, promoted the formation of compact and stable char layer. This study indicated that Lewis acidic and Brønsted acidic sites in BP altered the single degradation pathway and catalyzed the crosslinking and char forming of DPER. BP maybe as a potential acid source applied in intumescent flame retardant polymers in future. [ABSTRACT FROM AUTHOR]

The aim of this study is to synthesize a composite membrane having high proton conductivity, ion exchange capacity and chemical stability. In order to achieve this aim, poly(vinyl alcohol) (PVA) based composite membranes are synthesized by using classic sol–gel method. Boric acid (H 3 BO 3 ) and boron phosphate (BPO 4 ) are added to the membrane matrix in different ratios in order to enhance the membrane properties. Characterization tests, i.e; FT-IR analysis, mechanical strength tests, water hold-up capacities, swelling properties, ion exchange capacities, proton conductivities and fuel cell performance tests of synthesized membranes are carried out. As a result of performance experiments highest performance values are obtained for the membrane containing 15% boron phosphate at 0.6 V and 750 mA/cm 2 . Water hold-up capacity, swelling ratio, ion exchange capacity and proton conductivity of this membrane are found as 56%, 8%, 1.36 meq/g and 0.37 S/cm, respectively. These values are close to the values obtained ones for perfluorosulphonic acid membranes. Therefore this membrane can be regarded as a promising candidate for usage in fuel cells. [ABSTRACT FROM AUTHOR]

A composite membrane based on a non-stoichiometric composition of BPO 4 with excess of PO 4 (BPO x ) was synthesised and characterised for medium temperature fuel cell use (120–180 °C). The electrolyte was characterised by FTIR, SS-NMR, TGA and XRD and showed that the B–O is tetrahedral, in agreement with reports in the literature that boron phosphorus oxide compounds at B:P < 1 are exclusively built of borate and phosphate tetrahedra. Platinum micro electrodes were used to study the electrolyte compatibility and stability towards oxygen reduction at 150 °C and to obtain kinetic and mass transport parameters. The conductivities of the pure BPO x membrane electrolyte and a Polybenzimidazole (PBI)-4BPO x composite membrane were 7.9 × 10 −2 S cm −1 and 4.5 × 10 −2 S cm −1 respectively at 150 °C, 5%RH. Fuel cell tests showed a significant enhancement in performance of BPO x over that of typical 5.6H 3 PO 4 -PBI membrane electrolyte. The enhancement is due to the improved ionic conductivity (3×), a higher exchange current density of the oxygen reduction (30×) and a lower membrane gas permeability (10×). Fuel cell current densities at 0.6 V were 706 and 425 mA cm −2 for BPO x and 5.6H 3 PO 4 -PBI, respectively, at 150 °C with O 2 (atm). [ABSTRACT FROM AUTHOR]

Background and aims: Soluble boron (B) sources pose a risk of B toxicity to seedlings just after planting and leaching losses after application and before plant uptake. Boron phosphate (BPO) has low water solubility and slowly releases B, and hence could be safe for seedlings. Therefore, we investigated the toxicity of several B sources co-granulated with mono-ammonium phosphate (MAP) or co-compacted with potassium chloride referred to as muriate of potash (MOP) on canola seedlings. Methods: Ulexite, borax, colemanite and BPO compounds synthesized at 500 or 800 °C for 1 h were co-granulated with MAP or co-compacted with MOP at inclusion rates of 0.5, 1.0 and 2.0 % B. The seedling toxicity of these products was evaluated by placing a fertilizer granule in the centre of a soil-filled Petri dish in which canola was seeded. The area of the non-vegetated zone around the granule application site was evaluated after 7 and 12 days of growth. Results: Application of ulexite, borax and colemanite co-granulated with MAP resulted in toxicity symptoms at the lowest concentration of 0.5 % B, and the area of the affected zone increased with increasing concentrations of B in the granule, whereas no toxicity symptoms were observed with the application of co-granulated BPO products even at 2.0 % B content. Similar results were observed for the MOP fertilizers, except for colemanite which showed no toxicity when combined with MOP. Hot water-soluble B concentrations were measured in concentric sections around the granule application site and were in agreement with the toxicity results, with concentration in the toxic range close to the granule for the most soluble B sources. Conclusions: BPO is potentially a seedling-safe B fertilizer source. [ABSTRACT FROM AUTHOR]

A solid acid boron phosphate (BP) has been prepared and characterized by X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy. The catalytic effects of BP on pyrolysis and flame retardancy of epoxy resins (EP) were studied by various methods. Transmission electron microscopy images suggested that BP was uniformly dispersed into the EP matrix. Differential scanning calorimetry illustrated that loading of BP could slightly reduce the glass transition temperature of EP. Thermogravimetric analysis and Fourier-transform infrared spectrometry indicated that BP catalyzed EP to pyrolysis at a lower temperature, leading to a reduction of flammable gas release and an increased residue yield. Limiting oxygen index (LOI) and UL 94 data showed that when the BP loading was increased, the LOI value increased accordingly. In addition, the UL 94 level was improved from no rating to a V-1 rating. In cone calorimeter measurements, a compact intumescent “honeycomb-like” char layer was found for the EP/BP composites, which led to considerable decreases in the maximum peak of heat release rate and total heat released. A possible catalytic flame retardant mechanism for the EP/BP composites is proposed. [ABSTRACT FROM AUTHOR]

Highlights: [•] A novel 2,2′-diallylbisphenol A dicyanate ester (DA-BADCy) was prepared. [•] Using thiol-ene system, cyanate ester formulations were prepared at room temperature. [•] This study maintains ease of application for cyanate esters. [ABSTRACT FROM AUTHOR]

The effect of boron phosphate (BPO 4) nanoparticles on the mechanical, thermal, and flame retardant properties of polypropylene (PP) and polyamide 6 (PA-6) fibers are investigated by tensile testing, thermogravimetric analysis (TGA), differential scanning calorimeter (DSC), and micro combustion calorimeter (MCC). The addition of BPO 4 reduces the mechanical properties of the both PP and PA-6 fibers. According to the TGA results, the addition of BPO 4 does not change the thermal behavior of PP fiber and slightly reduces the thermal stability of PA-6 fiber by about 30 °C. According to MCC results, the addition of BPO 4 does not change the effective total heat evolution and heat release rate (HRR) peak for PP fibers. Although the inclusion of BPO 4 does not change the total heat evolution of PA-6 fiber, it reduces the HRR peaks due to increase in barrier effect of char. [ABSTRACT FROM AUTHOR]

Abstract: In this study novel flame retardant boron phosphate (BPO4)/polyimide composites were prepared. 4,4′-Oxydianiline (ODA) was reacted with 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BTDA) in dimethyl formamide (DMF) and mixed with BPO4 particles to obtain a series of polyamic acids, meanwhile, corresponding polyimides were synthesized via the thermal imidization technique. The amount of BPO4 in the composite films was varied from 0 wt% to 10 wt%. The structure, thermal and surface properties of the polyimide films were characterized by means of ATR-FTIR, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The flame retardancy of the composite materials was examined by limiting oxygen index (LOI) measurements and UL-94 VTM tests. Result showed that the LOI values of composites increased from 28 to 39. Furthermore, proton conductivity of polyimide films was measured by the four probe technique. The composite membrane containing 3 wt% of BPO4 showed a conductivity of 0.4 mS/cm at room temperature. [Copyright &y& Elsevier]

Abstract: The boron phosphate-poly(2,5-benzimidazole) (or BPO4–ABPBI) nanocomposite proton exchange membranes were prepared by preblending BPO4 nanoparticles to the 3,4-diaminobenzoic acid solution before its polycondensation. The phosphoric acid doped nanocomposite membrane possesses enhanced proton conductivity compared to the phosphoric acid doped pristine ABPBI membrane without BPO4 nanoparticles; and a maximum proton conductivity of 27.3 mS cm−1 was observed in the phosphoric acid doped nanocomposite membrane consisting of 25% BPO4 nanoparticles at 180 °C under anhydrous condition. The enhancement of proton conductivity is attributed to the dangling hydroxyl or geminal hydroxyl groups of the excess phosphoric acid molecules on surface of the BPO4 nanoparticles based on density functional theory calculations. In addition, the blending of BPO4 nanoparticles significantly decreases the methanol vapor permeability through the membrane by about two-fold. [Copyright &y& Elsevier]

Microencapsulated ammonium polyphosphate (MAPP) with polyurethane resin has been prepared by in situ polymerization. The combination of MAPP and boron phosphate (BP) on the flammability properties of thermoplastic polyurethane (TPU) was studied by vertical burning (UL-94) tests, limiting oxygen index tests, cone calorimetry (CONE), and microscale combustion calorimeter (MCC) whereas thermal stability was investigated by thermogravimetric analysis and real-time Fourier transform infrared. Results showed that a suitable substitution of MAPP by BP could improve flame retardancy of the TPU/MAPP composites and TPU composites with MAPP/BP (15.5/2 wt%) achieving UL-94 V-0 rating. The CONE and MCC data showed synergistic effects between BP and MAPP in the composites. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Composites were fabricated by blending SPSEBS (Sulfonated Poly Styrene Ethylene Butylene Poly Styrene) with Boron phosphate (BPO4) for proton conducting applications in fuel cells. The effects of boron phosphate and its relative loading were analyzed in terms of IEC and proton conductivity. Water and methanol uptake of these membranes were also studied. The membranes were characterized by IR spectroscopy. Thermal stability was studied by TGA and DSC analyses. Surface morphology was done by Scanning Electron Microscopy (SEM). The XRD studies indicated the existence of a certain level of crystallinity in the SPSEBS, and the composite membranes. Mechanical strength of the membranes was measured by Universal Testing Machine (UTM). This paper presents the result of recent investigations to develop an optimised in-house membrane electrode assembly (MEA) preparation technique combining catalyst ink spraying and assembly hot pressing. Easy steps were chosen in this preparation technique aiming at simplification and cost reduction. [Copyright &y& Elsevier]

Abstract: A new series of sulfonated poly(ether sulfone) (SPES)/boron phosphate (BPO4) composite membranes for proton-exchange membrane fuel cells (PEMFCs) applications, with a BPO4 content up to 40wt%, were prepared by a sol–gel method using tripropylborate and phosphoric acid as precursors. Compared to a pure SPES membrane, BPO4 doping in the membranes led to a higher thermal stability and glass-transition temperature (T g) as revealed by TGA–FTIR, DSC and DMTA. Water uptake and oxidative stability were significantly increased by increasing the content of BPO4. At both operating temperature conditions, namely 20°C and 100°C, the tensile strength of all the composite membranes were lower than that of the SPES membrane. However, even when the content of BPO4 was as high as 30%, the composite membrane still possessed strength similar to the Nafion 112 membrane. SEM–EDX indicated that the BPO4 particles were uniformly embedded throughout the SPES matrix, which may facilitate proton transport. Proton conductivities increased from 0.0065 to 0.022Scm−1 at room temperature as BPO4 increased from 0 to 40%. The conductivities also increased with the temperature. The SPES/BPO4 composite membrane is a promising candidate for PEMFCs applications, especially at higher temperatures. [Copyright &y& Elsevier]

Abstract: In this work, sulfonated poly(phthalazinone ether nitrile ketone)/boron phosphate (SPPENK/BPO4) composite membranes with BPO4 content from 10 to 30 wt.% were prepared from SPPENK matrix, tripropylborate (C3H7O)3B and phosphoric acid (H3PO4) via an in situ process. The composite membranes were characterized using X-ray diffraction, FT-IR and TGA, which revealed the interaction between the sulfonic acid groups of SPPENK and BPO4. The SPPENK/BPO4 composite membranes showed excellent thermal, oxidative and hydrolytic stabilities. The swelling ratios of composite membranes were about 5.0%, which was similar to that of SPPENK membrane. Proton conductivity of the composite membranes was studied under 100% relative humidity conditions up to 95 °C. A five-fold increase in proton conductivity was observed for the composite membrane with 30 wt.% BPO4. [Copyright &y& Elsevier]

Abstract: Sulfonated poly(ether ether ketone) (SPEEK)/boron phosphate (BPO4) composite membranes for polymer electrolyte fuel cells (PEFCs) were prepared via an in situ sol–gel process in our previous study [P. Krishnan, J.-S. Park, C.-S. Kim, Preparation of proton-conducting sulfonated poly(ether ether ketone)/boron phosphate composite membranes by an in situ sol–gel process, J. Membr. Sci. 279 (2006) 220]. Proton conductivity of the composite membranes increased with increasing the amount of BPO4 up to 40wt.% due to the increasing BPO4 particle size. In this study, the effect of several variables such as reaction time, reaction temperature and ionic form of solution-casting SPEEK polymers on the relationship between the size of inorganic particles and proton conductivity of the membranes was investigated for the preparation of SPEEK/BPO4 composite membranes. The composite membranes were characterized using FT-IR, SEM, DSC, TGA and proton conductivity. Among the variables, reaction time and reaction temperature were not dependent on the proton conductivity and size of BPO4 in the in situ sol–gel process. However, the ionic form of solution-casting polymers for the composite membranes significantly influenced the size of BPO4 particles. At the same amount of BPO4 in the composite membranes, the composite membrane using H+-form polymer made the BPO4 particle size five to six times higher than that using Na+-form polymer. Water uptake of the former composite membrane (in particular, an amount of freezable water) was higher than the latter due to the bigger size of BPO4, and the proton conductivity of the former composite membrane increased. As a result, it can be recommended that the preparation of the composite membranes using H+-form polymer is preferable via the in situ sol–gel process. [Copyright &y& Elsevier]