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High internal phase emulsions (HIPEs) have been of great interest for fabricating fluorinated porous polymers having controlled pore structures and excellent physicochemical properties. However, it remains a challenge to prepare stable fluorocarbon HIPEs, due to the lack of suitable surfactants. By randomly grating hydrophilic and fluorophilic side chains to polyphosphazene (PPZ), a comb-like amphiphilic PPZ surfactant with biodegradability is designed and synthesized for stabilizing water/fluorocarbon oil-based emulsions. The hydrophilic-lipophilic balance of PPZs can be controlled by tuning the grating ratio of the two side chains, leading to the preparation of stable water-in-oil HIPEs and oil-in-water emulsions, and the production of fluorinated porous polymers and particles by polymerizing the oil phase. These fluorinated porous polymers show excellent thermal stability and, due to the hydrophobicity and porous structure, applications in the field of oil/water separation can be achieved.

In this study, the challenges of brittleness and flammability in Polyamide 6/glass fiber (PA6/GF) composites, which are crucial for heat‐resistant and stress‐bearing structural parts, are addressed. Polyphosphazene (PZ) elastomers, known for their exceptional flame‐retardant properties, are introduced to enhance the robustness and safety of these composites. Specifically, poly(diaryloxy)phosphazene (PDAP) and poly(difluoroalkoxy)phosphazene (PDFP) are utilized, both contributing to the improved toughness and flame resistance of the PA6/GF composites. Experimental results show that PDAP mainly played the role of solid‐phase flame retardant, while PDFP mainly acted the role of gas‐phase flame retardant. For PA/PZs composites without adding GF, PDFP plays a more efficient flame retardant effect than PDAP. By introducing 15 Vol% of PDFP, the limiting oxygen index (LOI) of the composite reached 26.1%, while the notched impact strength increased by 297%. For PA/PZs/GF composites, PDAP plays a better flame retardant role than PDFP. Under the action of 30 vol% GF and 15 vol% PDAP, the LOI of PA6/PDAP/GF composite reached 26.8%, and the notch impact strength improved to 18.7 kJ/m2, which is 165% higher than that of PA6/GF, and the UL‐94 test reaches V‐0 level. The findings of the study highlight the potential of PDAP and PDFP to act as dual‐function modifiers. These modifiers can considerably ameliorate both the impact resistance and flame retardancy of PA6 and PA6/GF composites. Such dual enhancement surpasses the typical trade‐offs seen in conventional composites, indicating a constructive direction for future material innovation. Highlights: Polyphosphazenes simultaneously enhance PA6's toughness & flame resistance.Distinct flame retardant mechanisms found in PDAP and PDFP.GF presence alters PDAP and PDFP's flame retardant efficacy.PDAP shows superior flame resistance in GF‐reinforced PA6 composites.Without GF, PDFP outperforms PDAP in enhancing flame retardancy. [ABSTRACT FROM AUTHOR]

Diphenolic acid/furfurylamine‐based bio‐benzoxazine (DPA‐fa‐Boz) was selected here as the starting material to prepare a phenol hydroxyl‐containing polyamide (PA) derivative, PA‐DFB, via sustainable benzoxazine‐isocyanide mechanochemistry (BIC‐MC). Further, a type of PA/phosphazene‐based, organic–inorganic covalent hybrid (PD‐HCCP), which comprises various N/P/O‐containing substructures (NP ring, amide, carboxylic acid, and tertiary amine), was successfully prepared by the condensation between PA‐DFB and hexachlorocyclotriphosphazene (HCCP). The presence of heteroatoms‐containing segments endows PD‐HCCP with specific affinity for some cationic agents. PD‐HCCP's binding capability for Pb(II) can be feasibly utilized for the detection of this heavy metal. The downstream application investigation of PD‐HCCP revealed that it can be used as an enrichment‐type Pb(II) electrochemical probe, characterizing a wide detection range (1–40 μM) and a low detection limit (0.0245 μM). Meanwhile, PD‐HCCP also showed the selective binding for cationic dye, methylene blue (MB), providing a maximum adsorption capacity of ~424.97 mg/g and a high adsorption rate (with 98% removal efficiency at 6 min), with the pseudo‐second‐order rate constant up to 0.0325 g mg−1 min−1. [ABSTRACT FROM AUTHOR]

Current electric storage systems eagerly focus on high‐power and energy‐dense Lithium‐ion batteries to cope with increasing energy storage demands. Since cathode materials are one of the bottlenecks of these batteries, there is much interest in layered lithium‐rich manganese oxide‐based (LLMO) cathodes which can develop this technology. However, Initial Coulombic Efficiency (ICE) loss, poor rate performance and cycling instability issues are still persistent as problems to be solved for these materials. Recent research shows that water‐soluble binders are effective in improving the performance of LLMO materials. Herein, we describe the synthesis, characterisation, and application of a series of water‐soluble composites as a binder for LLMO cathodes. The PPy is introduced as part of the binder to improve the electronic conductivity and two different oxidants and various PPy to PSAP ratios were used to optimise the final properties. The electrochemical performance and morphology of the cathodes before and after cycling were investigated and compared with the conventional PVDF binder. The LLMO−2c electrode showed excellent charge‐discharge performance, especially at 5 C and 10 C rates, and high cycling stability at 0.2 C whilst maintaining a final capacity of 184 mAh/g after 200 cycles, which is equal to 89.3 % capacity retention. [ABSTRACT FROM AUTHOR]

Copyright of Fire Safety Science is the property of Fire Safety Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The cell performance of Li−S batteries can be improved by establishing compatibility with the electrolyte of cathode and enhancing lithium‐ion diffusion (ionic conductivity) or electrical conductivity. In this work, we introduce cathode material based on ethylene glycol‐containing acrylic polyphosphazene. Poly[(2acrylamidoethoxy)‐random‐(methoxyethoxyethoxy)] phosphazenes were synthesized by macromolecular substitution of poly(dichloro)phosphazene with 2‐acrylamidoethanol and diethylene glycol methyl ether in two different ratios (25 and 50 mol% of ethylene glycol methyl ether), abbreviated as MP‐25EG and MP‐50EG, where ethylene glycol chains enhance the electrolyte compatibility and ion transport of the sulfur cathode material. Then, poly[S‐random‐(2acrylamidoethoxy)‐random‐(methoxyethoxyethoxy)] phosphazene polymers, designated as MP‐25EG‐xS or MP‐50EG‐xS (x=50 and 80 wt.% of sulfur) were prepared by inverse vulcanization of polymer with two feed sulfur ratios. Structural characterizations of the polymers were carried out using appropriate standard spectroscopic methods such as 1H and 31P NMR, FT‐IR, DSC and TGA as well as XPS. The electrochemical performance of MP‐25EG‐50S, MP‐25EG‐80S and MP‐50EG‐50S, MP‐50EG‐80S were evaluated and the effect of ethylene glycol was investigated by comparing cell performances. MP‐50EG‐50S demonstrated its promising applicability in Li–S batteries by exhibiting much better electrochemical respond with a discharge capacity of 745 mAh/g at C/5 current density over 100 cycles. [ABSTRACT FROM AUTHOR]

Aluminum hypophosphite microspheres (AHP) were synthesized by hydrothermal method using NaH2PO2-H2O and AlCl3·6H2O as raw materials, and then the AHP microspheres were polymerized by surface polymerization of micro-nanospheres with cyclic cross-linked poly(cyclotriphosphazene-co-4. 4′-sulfonyldiphenol) (PZS). A new organic-inorganic poly(phosphonitrile)-modified aluminum hypophosphite microspheres (PZS-AHP) were synthesized by encapsulation and applied to flame retardant thermoplastic polyurethane (TPU). The microstructure and chemical composition of the PZS-AHP microsphere were characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy and X-ray spectroscopy. The thermal stability of PZS-AHP microsphere was explored with thermogravimetric analysis. Thermogravimetric data indicate that the PZS-AHP microspheres have excellent thermal stability. The thermal and flame-retarding properties of the TPU composites were evaluated by thermogravimetric (TG), limited oxygen index tests (LOI), and cone calorimeter test (CCT). The TPU composite achieved vertical burning (UL-94) V-0 grade and LOI value reached 29.2% when 10 wt% PZS-AHP was incorporated. Compared with those of pure TPU, the peak heat release rate (pHRR) and total heat release (THR) of TPU/10%PZS-AHP decreased by 82.2% and 42.5%, respectively. The results of CCT indicated that PZS-AHP microsphere could improve the flame retardancy of TPU composites. [ABSTRACT FROM AUTHOR]

"Hot spot" 19F magnetic resonance imaging (MRI) has garnered significant attention recently for its ability to image various disease markers quantitatively. Unlike conventional gadolinium-based MRI contrast agents, which rely on proton signal modulation, 19F-MRI's direct detection has a unique advantage in vivo, as the human body exhibits a negligible background 19F-signal. However, existing perfluorocarbon (PFC) or PFC-based contrast materials suffer from several limitations, including low longitudinal relaxation rates and relatively low imaging efficiency. Hence, we designed a macromolecular contrast agent featuring a high number of magnetically equivalent 19F-nuclei in a single macromolecule, adequate fluorine nucleus mobility, and excellent water solubility. This design utilizes superfluorinated polyphosphazene (PPz) polymers as the 19F-source; these are modified with sodium mercaptoethanesulfonate (MESNa) to achieve water solubility exceeding 360 mg/mL, which is a similar solubility to that of sodium chloride. We observed substantial signal enhancement in MRI with these novel macromolecular carriers compared to non-enhanced surroundings and aqueous trifluoroacetic acid (TFA) used as a positive control. In conclusion, these novel water-soluble macromolecular carriers represent a promising platform for future MRI contrast agents. [ABSTRACT FROM AUTHOR]

Lithium-ion polymer batteries, also known as lithium-polymer, abbreviated Li-po, are one of the main research topics nowadays in the field of energy storage. This review focuses on the use of the phosphorus containing compounds in Li-po batteries, such as polyphosphonates and polyphosphazenes. Li-po batteries are mini-devices, capable of providing power for any portable gadget. From a constructive point of view, Li-po batteries contain an anode (carbon), a cathode (metal oxide), and a polymer electrolyte, which could be liquid electrolytes or solid electrolytes. In general, a divider is used to keep the anode and cathode from touching each other directly. Since liquid electrolytes have a generally high ionic conductivity, they are frequently employed in Li-ion batteries. In the last decade, the research in this field has also focused on solving safety issues, such as the leakage of electrolytes and risk of ignition due to volatile and flammable organic solvents. The research topics in the field of Li-po remain focused on solving safety problems and improving performance. [ABSTRACT FROM AUTHOR]

A leap‐forward approach has been successfully devised to synthesize a novel hierarchical binary metal modified heteroatom doped 2D micro‐/mesporous carbon‐graphene nanostructure (NPSMC@Ir−Ru@rGO) for overall water splitting application. To investigate the role of decorating metals, different electrolcatalysts like NPSMC, NPSMC@rGO, NPSMC@Ir@rGO, and NPSMC@Ru@rGO were also synthesized and structural changes were compared and investigated by physiochemical techniques. All of the samples have shown electrocatalytic activities attributed to the presence of heteroatom (N, P, S) doped micro‐/mesoporous carbonaceous matrix, amorphous carbon in the coexistence of graphitic lattice carbons, presence of active metal NPs (Ir and/‐or Ru), an even distribution of active sites, and graphene 2D interconnected channels to promote electron transfer ability, respectively. However, the Ir−Ru metal codeped nanocatalyst (NPCMS@Ir−Ru@rGO) is proved to be an excellent electrocatalyst based on the synergistic role of Ir−Ru metals that necessitates the low overpotentials of 181 mV and 318 mV to convey a current density of 10 mA cm−2 towards the electroctalytic application of HER and OER, respectively. Furthermore, exhibiting the corresponding Tafel slopes (132 and 70 mV dec−1) in an alkaline medium. This work is anticipated to open up new avenues for the development of promising electrocatalysts based on active metals modified heteroatom doped carbon nanomaterials for energy applications. [ABSTRACT FROM AUTHOR]

The extremely flammable cellulose macromolecules in cotton fabrics seriously affect their application in the field of flame retardancy. In this paper, the surface of cotton fabric was modified with citric acid, and then metal-organic framework (UiO-66), cationic starch (St) and polyphosphonitrile (PZS) microspheres containing the transition metal element Zr were sequentially deposited to prepare an efficient and economical cotton fabric. St-PZS double-impregnated cotton fabrics have better thermal stability, flame retardancy and mechanical properties. And the coating does not affect the whiteness and stiffness of the cotton fabric. The results of thermogravimetric analysis showed that cotton/UiO-66/2St-PZS had a higher residual char rate (25.34%) under N2 atmosphere, which was 200.1% higher than that of control cotton (8.28%). In addition, cotton/UiO-66/2St-PZS had a 46.6% reduction in peak heat release, a 31.7% reduction in total heat release, and a 35.3% reduction in the peak of CO2 production compared to control cotton. It is worth noting that the average gross calorific value is 63.3% lower than that of the control cotton, indicating that flame retardant cotton fabrics can effectively inhibit the production of flammable gases. In addition, the tensile strength and elongation at break of cotton/UiO-66/2St-PZS are 458.79 N and 11.04%, respectively. After 20 laundering cycles, the mechanical properties remained almost unchanged.

Abstract The cell performance of Li−S batteries can be improved by establishing compatibility with the electrolyte of cathode and enhancing lithium‐ion diffusion (ionic conductivity) or electrical conductivity. In this work, we introduce cathode material based on ethylene glycol‐containing acrylic polyphosphazene. Poly[(2acrylamidoethoxy)‐random‐(methoxyethoxyethoxy)] phosphazenes were synthesized by macromolecular substitution of poly(dichloro)phosphazene with 2‐acrylamidoethanol and diethylene glycol methyl ether in two different ratios (25 and 50 mol% of ethylene glycol methyl ether), abbreviated as MP‐25EG and MP‐50EG, where ethylene glycol chains enhance the electrolyte compatibility and ion transport of the sulfur cathode material. Then, poly[S‐random‐(2acrylamidoethoxy)‐random‐(methoxyethoxyethoxy)] phosphazene polymers, designated as MP‐25EG‐xS or MP‐50EG‐xS (x=50 and 80 wt.% of sulfur) were prepared by inverse vulcanization of polymer with two feed sulfur ratios. Structural characterizations of the polymers were carried out using appropriate standard spectroscopic methods such as 1H and 31P NMR, FT‐IR, DSC and TGA as well as XPS. The electrochemical performance of MP‐25EG‐50S, MP‐25EG‐80S and MP‐50EG‐50S, MP‐50EG‐80S were evaluated and the effect of ethylene glycol was investigated by comparing cell performances. MP‐50EG‐50S demonstrated its promising applicability in Li–S batteries by exhibiting much better electrochemical respond with a discharge capacity of 745 mAh/g at C/5 current density over 100 cycles.

[Display omitted] Au coated magnetic polyphosphazene (MPCTP) composite particles (MPCTP@Au) were fabricated with sensitive SERS activity. The MPCTP particles were generated by coating polyphosphazene on Fe 3 O 4 nanoparticles through precipitation polycondensation of hexachlorocyclotriphosphazene and phloroglucinol. MPCTP@Au composite particles were obtained by deposition of Au nanoparticles on MPCTP by the reduction of HAuCl 4. The size and the thickness of the Au shell can be controlled by varying the amount of HAuCl 4. The magnetic core endowed the composite particles with good magnetic responsiveness, which allowed the analyte to be enriched and separated from the complex matrix, and significantly simplifying the sample pretreatment procedure. The SERS activity of MPCTP@Au composite particles were evaluated by DTNB as model Raman reporter, and the limits of detection (LOD) of DTNB was 10-8 mol/L. A high efficient SERS immunoassay system based on the MPCTP@Au substrates for the detection of immunoproteins was developed. Human IgG and rabbit IgG were quantitatively determinated simultaneously by this immunoassay system. The quantitative determination of the immunoglobulin G (IgG) was achieved and the LOD of human IgG, rabbit IgG and the mixture of human IgG and rabbit IgG were as low as 10 fg/mL, 100 pg/mL and 1 ng/mL, respectively. The results showed that the MPCTP@Au composite particles have broad application prospects as high performance SERS active substrates for immunoprotein analysis. [ABSTRACT FROM AUTHOR]

To enhance the capacity of supercapacitors, hybrid materials with diverse dopants need to be developed as they have a synergistic effect. This study was conducted to prepare the quaternary (N, P, O, and S) Co3O4-doped carbons by uniformly growing the heteroatom-holding poly-(cyclotriphosphazene-co-4,4-sulfonyldiphenol) (PZS) polymer on the cobalt-containing zeolitic imidazolate framework (ZIF-67) with a polyhedral morphology. Different carbonization temperatures were used to control the contents of the elements. Co3O4–NPS-800 was found to have optimized contents of heteroatoms (N 6.13, P 2.91, O 21.37, and S 13.73 wt %), a surface area of 762 m2/g, exhibited a high specific capacity (815 F g–1 at 1 A g–1) and good rate capability (617 F g–1 at 10 A g–1), as well as excellent long-term cyclic stability with 86% capacitance retention and 100% Coulombic efficiency over 10,000 cycles. This was attributed to the synergistic effect of heteroatoms along with Co3O4, which not only broke the inertness of the carbon structure but also increased the electron transfer tendency and produced a Lewis base surface that promoted maximum exposure to electroactive sites, resulting in a remarkable electrochemical performance. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The venture to fabricate potential and functional bone regeneration, annihilating the health complexities in conventional bone grafting, made Bone tissue engineering (BTE), which facilitates meticulous control of the spatial and temporal dissemination of cells and extracellular matrix (ECM), receive incredible consideration in the past few years. Ascribable to their exceptional properties, polymers have gotten significant attention as one of the prominent classes of biomaterials for BTE. The compatible mechanical properties, biocompatibility, bioactivity, and biodegradability of polyphosphazene/hydroxyapatite composite made them candidates for functional bone regeneration. This review demonstrates the synthesis, properties, and application of polyphosphazenes, hydroxyapatite, and composite biomaterial for BTE. [ABSTRACT FROM AUTHOR]

[Display omitted] • P/S/N co-doping and carbon-coating of yolk-shelled CoMoO 4 nanospheres are realized in one-pot. • PSN-C@CoMoO 4 displays high lithium storage capacity and excellent cycle/rate performance. • PSN-C@CoMoO 4 shows enhanced electronic conductivity and robust structural stability. Transition metal oxides as potential anodes of lithium-ion batteries (LIBs) possess high theoretical capacity but suffer from large volume expansion and poor conductivity. To overcome these drawbacks, we designed and fabricated polyphosphazene-coated yolk-shelled CoMoO 4 nanospheres, in which polyphosphazene with abundant C/P/S/N species was readily converted into carbon shells and provided P/S/N dopants. This resulted in the formation of P/S/N co-doped carbon-coated yolk-shelled CoMoO 4 nanospheres (PSN-C@CoMoO 4). The PSN-C@CoMoO 4 electrode exhibits superior cycle stability of 439.2 mA h g−1 at 1000 mA g−1 after 500 cycles and rate capability of 470.1 mA h g−1 at 2000 mA g−1. The electrochemical and structural analyses reveal that PSN-C@CoMoO 4 with yolk-shell structure, coated with carbon and doped with heteroatom not only greatly enhances the charge transfer rate and reaction kinetics, but also efficiently buffers the volume variation upon lithiation/delithiation cycling. Importantly, the use of polyphosphazene as coating/doping agent can be a general strategy for developing advanced electrode materials. [ABSTRACT FROM AUTHOR]

Polyphosphazene derivatives are gaining popularity due to their eco-friendly character and high content of flame-retardant components. Herein, a polyphosphazene derivative (PZAF) microsphere was successfully synthesized utilizing an in-situ template approach, which was then employed as an additive flame retardant in polyethylene terephthalate (PET) to improve the fire safety. Thermogravimetric analysis revealed that PZAF promoted the pyrolysis of PET in advance to generate a stable char layer that protects the matrix from heat, consequently increasing char residues. With addition of 10 wt% PZAF, the PET nanocomposites obtained a V-0 grade in vertical combustion test and its LOI value increased from 24.2 vol% to 32.1 vol%. Moreover, the peak heat release and carbon monoxide production decreased by 46.6% and 50.6%, respectively. This was because the phosphonic acid fragments and pyridine ring compounds produced by the PZAF pyrolysis encouraged the development of a robust char layer. Meanwhile, the •PO radicals generated by the pyrolysis of PZAF could capture free radicals in the gas phase, ultimately ending the chain reaction of combustion. Also, mechanical properties of the PET nanocomposites were noticeably enhanced by the addition of 3 or 5 wt% PZAF. [ABSTRACT FROM AUTHOR]

Synthetic polymer materials have been surged to the forefront of research in the fields of tissue engineering, drug delivery, and biomonitoring in recent years. Biodegradable synthetic polymers are increasingly needed as transient substrates for tissue regeneration and medicine delivery. In contrast to commonly used polymers including polyesters, polylactones, polyanhydrides, poly(propylene fumarates), polyorthoesters, and polyurethanes, biodegradable polyphosphazenes (PPZs) hold great potential for the purposes indicated above. PPZ's versatility in the synthetic process has enabled the production of a variety of polymers with various physico‐chemical, and biological properties have been produced, making them appropriate for biomedical applications. Biocompatible PPZs are often used as scaffolds in the regeneration of skeleton, bones, and other tissues. PPZs have also received special attention as potential drug vehicles of high‐value biopharmaceuticals such as anticancer drugs. Additionally, by incorporating fluorophores into the PPZ backbone to produce photoluminescent biodegradable PPZs, the utility of polyphosphazenes is further expanded as they are used in tracking the regeneration of the target tissue as well as the fate of PPZ based scaffolds or drug delivery vehicles. This review provides a summary of the evolution of PPZ applications in the fields of tissue engineering, drug delivery, and bioimaging in recent 5 years. [ABSTRACT FROM AUTHOR]

In this study, a new type of ceramic composite (PZSC/ZnO) was successfully synthesized using N, P, and S co‐doped carbon microspheres derived from polyphosphazene with zinc oxide. The morphology and structure were characterized by Fourier transform infrared spectroscopy, X‐ray photoelectron spectroscopy, scanning electron microscopy, energy‐dispersive spectroscopy, Raman, X‐ray diffraction, BET, and thermogravimetric. Batch experiments were used to explore the adsorption performance under different pH values, initial concentrations, contact times, and temperatures. The results showed that the maximum adsorption capacity of the PZSC/ZnO ceramic composite for uranium was 470.5 mg/g (pH = 5.5, t = 40 min, and T = 25°C). The adsorption process followed the nonlinear Langmuir model and the pseudo‐second‐order kinetic model, demonstrating that the monolayered combination of U(VI) with the PZSC/ZnO ceramic composite and the adsorption mechanism was chemical adsorption. Thermodynamic data revealed that the adsorption was a spontaneous endothermic process. Furthermore, P and N may be involved in the adsorption of uranyl ions through binding to the O atoms from ZnO. The main forces between U(VI) and the PZSC/ZnO ceramic composite were attributed to ZnO and heteroatoms doped in the material. [ABSTRACT FROM AUTHOR]

“Hot spot” 19F magnetic resonance imaging (MRI) has garnered significant attention recently for its ability to image various disease markers quantitatively. Unlike conventional gadolinium-based MRI contrast agents, which rely on proton signal modulation, 19F-MRI’s direct detection has a unique advantage in vivo, as the human body exhibits a negligible background 19F-signal. However, existing perfluorocarbon (PFC) or PFC-based contrast materials suffer from several limitations, including low longitudinal relaxation rates and relatively low imaging efficiency. Hence, we designed a macromolecular contrast agent featuring a high number of magnetically equivalent 19F-nuclei in a single macromolecule, adequate fluorine nucleus mobility, and excellent water solubility. This design utilizes superfluorinated polyphosphazene (PPz) polymers as the 19F-source; these are modified with sodium mercaptoethanesulfonate (MESNa) to achieve water solubility exceeding 360 mg/mL, which is a similar solubility to that of sodium chloride. We observed substantial signal enhancement in MRI with these novel macromolecular carriers compared to non-enhanced surroundings and aqueous trifluoroacetic acid (TFA) used as a positive control. In conclusion, these novel water-soluble macromolecular carriers represent a promising platform for future MRI contrast agents.

Lithium-ion polymer batteries, also known as lithium-polymer, abbreviated Li-po, are one of the main research topics nowadays in the field of energy storage. This review focuses on the use of the phosphorus containing compounds in Li-po batteries, such as polyphosphonates and polyphosphazenes. Li-po batteries are mini-devices, capable of providing power for any portable gadget. From a constructive point of view, Li-po batteries contain an anode (carbon), a cathode (metal oxide), and a polymer electrolyte, which could be liquid electrolytes or solid electrolytes. In general, a divider is used to keep the anode and cathode from touching each other directly. Since liquid electrolytes have a generally high ionic conductivity, they are frequently employed in Li-ion batteries. In the last decade, the research in this field has also focused on solving safety issues, such as the leakage of electrolytes and risk of ignition due to volatile and flammable organic solvents. The research topics in the field of Li-po remain focused on solving safety problems and improving performance.

Abstract Synthetic polymer materials have been surged to the forefront of research in the fields of tissue engineering, drug delivery, and biomonitoring in recent years. Biodegradable synthetic polymers are increasingly needed as transient substrates for tissue regeneration and medicine delivery. In contrast to commonly used polymers including polyesters, polylactones, polyanhydrides, poly(propylene fumarates), polyorthoesters, and polyurethanes, biodegradable polyphosphazenes (PPZs) hold great potential for the purposes indicated above. PPZ's versatility in the synthetic process has enabled the production of a variety of polymers with various physico‐chemical, and biological properties have been produced, making them appropriate for biomedical applications. Biocompatible PPZs are often used as scaffolds in the regeneration of skeleton, bones, and other tissues. PPZs have also received special attention as potential drug vehicles of high‐value biopharmaceuticals such as anticancer drugs. Additionally, by incorporating fluorophores into the PPZ backbone to produce photoluminescent biodegradable PPZs, the utility of polyphosphazenes is further expanded as they are used in tracking the regeneration of the target tissue as well as the fate of PPZ based scaffolds or drug delivery vehicles. This review provides a summary of the evolution of PPZ applications in the fields of tissue engineering, drug delivery, and bioimaging in recent 5 years.

The flame-retardant polyamide 66 composites (FR-PA66) were prepared by in situ loading of amino-functionalized polyphosphazene microspheres (HCNP), which were synthesized in the laboratory and confirmed by a Fourier transform infrared spectrometer (FTIR), scanning electron microscope (SEM), and transmission electron microscope (TEM). The thermal stabilities and flame retardancy of FR-PA66 were measured using thermogravimetric analysis (TGA), a thermogravimetric infrared instrument (TG-IR), the limiting oxygen index (LOI), the horizontal and vertical combustion method (UL-94), and a cone calorimeter. The results illustrate that the volatile matter of FR-PA66 mainly contains carbon dioxide, methane4, and water vapor under heating, accompanied by the char residue raising to 14.1 wt% at 600 °C and the value of the LOI and UL-94 rating reaching 30% and V-0, respectively. Moreover, the addition of HCNP decreases the peak of the heat release rate (pHRR), total heat release (THR), mass loss (ML), and total smoke release (TSR) of FR-PA66 to 373.7 kW/m2, 106.7 MJ/m2, 92.5 wt%, and 944.8 m2/m2, respectively, verifying a significant improvement in the flame retardancy of PA66. [ABSTRACT FROM AUTHOR]

With the rapid development of electronic devices, the corresponding energy storage equipment has also been continuously developed. As important components, including electrodes and diaphragms, in energy storage device and energy storage and conversion devices, they all face huge challenges. Polyphosphazene polymers are widely used in various fields, such as biomedicine, energy storage, etc., due to their unique properties. Due to its unique design variability, adjustable characteristics and high chemical stability, they can solve many related problems of energy storage equipment. They are expected to become a new generation of energy materials. This article briefly introduces the research progress in energy based on polyphosphazene materials in the past ten years, on topics such as fuel cells, solar cells, lithium batteries and supercapacitors, etc. The main focus of this work is on the defects of different types of batteries. Scholars have introduced different functional group modification that solves the corresponding problem, thus increasing the battery performance. [ABSTRACT FROM AUTHOR]

Ebolavirus (EBOV) infection in humans is a severe and often fatal disease, which demands effective interventional strategies for its prevention and treatment. The available vaccines, which are authorized under exceptional circumstances, use viral vector platforms and have serious disadvantages, such as difficulties in adapting to new virus variants, reliance on cold chain supply networks, and administration by hypodermic injection. Microneedle (MN) patches, which are made of an array of micron-scale, solid needles that painlessly penetrate into the upper layers of the skin and dissolve to deliver vaccines intradermally, simplify vaccination and can thereby increase vaccine access, especially in resource-constrained or emergency settings. The present study describes a novel MN technology, which combines EBOV glycoprotein (GP) antigen with a polyphosphazene-based immunoadjuvant and vaccine delivery system (poly[di(carboxylatophenoxy)phosphazene], PCPP). The protein-stabilizing effect of PCPP in the microfabrication process enabled preparation of a dissolvable EBOV GP MN patch vaccine with superior antigenicity compared to a non-polyphosphazene polymer-based analog. Intradermal immunization of mice with polyphosphazene-based MN patches induced strong, long-lasting antibody responses against EBOV GP, which was comparable to intramuscular injection. Moreover, mice vaccinated with the MN patches were completely protected against a lethal challenge using mouse-adapted EBOV and had no histologic lesions associated with ebolavirus disease. [ABSTRACT FROM AUTHOR]

[Display omitted] • The adsorption capacity of the composite was significantly enhanced to 399.6 mg/g within 80 min at pH 5 and 298.15 K. • The composite exhibits excellent selectivity and recyclability. • XPS and DFT analyses have confirmed the coordination interaction between the uranyl ion and nitrogen in TAC, and the role of sulfur vacancies from MoS 2. Uranium serves as a fundamental element for sustainable nuclear reactor energy. Hence, the extraction and enrichment of uranium from radioactive wastewater is of considerable significance for both nuclear power utilization and environmental protection. In this study, carbon microspheres (TAC) doped with nitrogen, phosphorus and sulfur were derived from ternary polyphosphazene. Subsequently, molybdenum disulfide (MoS 2) was integrated using hydrothermal method to fabricate the TAC/MoS 2 composite, which is designed for the efficient enrichment and separation of uranyl ions. Owing to the unique two-dimensional structure of MoS 2 and its strong affinity towards uranyl ions, the adsorption capacity of the composite was significantly enhanced to 399.6 mg/g within 80 min at pH 5 and 298.15 K. Additionally, the composite exhibited commendable thermal stability and hydrophilicity, declaring that it is an outstanding candidate for the efficient enrichment and separation of uranyl ions. Further mechanism studies through XPS analysis and DFT calculations suggested that the vacancies introduced by MoS 2 can generate electrostatic interactions and coordination effects with uranyl ions, thereby improving the adsorption performance of the composite. Due to its straightforward preparation process and exceptional adsorption performance, TAC/MoS 2 possesses broad application prospects in the extraction of uranium from wastewater. [ABSTRACT FROM AUTHOR]

Composite insulator is an important component of the power system which has high requirements for insulating properties, hydrophobicity, long-term reliability, and safety. Aiming to improve the comprehensive performance of composite insulators, we propose a novel composite based on polyphosphazene matrix and inorganic fillers including h-BN, SiO 2 and aramid pulp (AF-p). By the synergistic effect of the optimized chemical structure of polyphosphazene and modification by multi-scale hydrophobic electrical insulation fillers, the poly(difluoroalkoxy)phosphazenes (PDFP) composite presents enhanced hydrophobicity with the static water contact angle (WCA) up to 154° and rolling angle (RA) as low as 8°. Benefiting from the multiscale roughness constructed by multi-fillers, the PDFP composite exhibits superior mechanical durability. The contact angle of the sample still exceeds 150° after abrasion by sandpaper (800#) for 1000 cm. Meanwhile, with the addition of hybrid insulation fillers, the Weibull breakdown strength of PDFP/30h-BN/10SiO 2 -200/6AF-p is improved by 76 % compared to PDFP. Besides, the unique elemental composition of PDFP endows the PDFP composite with excellent flame retardancy with a 55 % limiting oxygen index and V-0 of the UL-94 grade, which guarantees safety for insulator applications. The results confirm the great potential of polyphosphazene for composite insulators. [Display omitted] • The potential application value of polyphosphazene elastomers in composite insulators is explored. • Fluoroalkoxy side groups in polyphosphazene can effectively improve hydrophobic performance. • Multi-scale fillers endow bulk poly (difluoroalkoxy)phosphazene (PDFP) composite with wear-resistant superhydrophobicity. • PDFP composite exhibits excellent flame retardancy ensuring the safety of composite insulators. [ABSTRACT FROM AUTHOR]

Thermoplastic polyurethane (TPU) is widely used in daily life due to its characteristics of light weight, high impact strength, and compression resistance. However, TPU products are extremely flammable and will generate toxic fumes under fire attack, threatening human life and safety. In this article, a nanohybrid flame retardant was designed for the fire safety of TPU. Herein, Co3O4 was anchored on the surface of exfoliated ultra-thin boron nitride nanosheets (BNNO@Co3O4) via coprecipitation and subsequent calcination. Then, a polyphosphazene (PPZ) layer was coated onto BNNO@Co3O4 by high temperature polymerization to generate a nanohybrid flame retardant named BNNO@Co3O4@PPZ. The cone calorimeter results exhibited that the heat release and smoke production during TPU combustion were remarkably restrained after the incorporation of the nanohybrid flame retardant. Compared with pure TPU, the peak heat release rate (PHRR) decreased by 44.1%, the peak smoke production rate (PSPR) decreased by 51.2%, and the peak CO production rate (PCOPR) decreased by 72.5%. Based on the analysis of carbon residues after combustion, the significant improvement in fire resistance of TPU by BNNO@Co3O4@PPZ was attributed to the combination of quenching effect, catalytic carbonization effect, and barrier effect. In addition, the intrinsic mechanical properties of TPU were well maintained due to the existence of the PPZ organic layer. [ABSTRACT FROM AUTHOR]

Novel inorganic-organic hybrid highly crosslinked and fluorescent polyphosphazene nanospheres were prepared via a one pot polycondensation polymerization method. Fluorescein and 4,4′-diaminodiphenylmethane were used as organic monomers in the synthesis of the nanospheres. The crosslinked structure of the nanospheres was formed with inorganic octachlorocyclotetraphosphazene rings. The characterization of the prepared nanospheres was performed by SEM, EDX, solid-state 31P-NMR, FTIR, XPS, XRD, DLS, and UV-vis techniques. The average particle size of the nanospheres was determined to be 343 nm. The fluorescence properties of the nanospheres were investigated. When they were excited at 470 nm, the nanospheres exhibited a fluorescence emission at 520 nm in ethanol. However, they did not show fluorescence emission at solid state. The nanospheres exhibited maximum emission at pH 9.0. The synthesized nanospheres have excellent photostability in 60 minutes at pH 9.0 owing to the crosslinked and inorganic-organic hybrid structure. [ABSTRACT FROM AUTHOR]

The novel polyphosphazene and cyclomatrix type microspheres were synthesized via a one-pot self-assembly polycondensation method. Octachlorocyclotetraphosphazene and two fluorescent compounds; fluorescein and curcumin were used as a crosslinker and monomers, respectively. The prepared microspheres were characterized by SEM, EDX, FTIR, XRD, UVvis techniques. Also, the fluorescence properties of the microspheres were investigated. The microspheres exhibited fluorescence emissions both in ethanol and as solid-state when excited at 470 nm. The optimum pH was determined as 9.0 for fluorescence measurements. Owing to fluorescent properties of the microspheres, the delivery of curcumin from the prepared microspheres, and cell imaging can be investigated in the future. It is thought that the obtained intrinsically fluorescent polyphosphazene microspheres have the potential for use as sensors and labels, also. [ABSTRACT FROM AUTHOR]

Particular precursors with controllable micromorphology and unique element composition were prepared by hyper-cross-linked (naphthoxylic/trifluoroethoxylic) cyclotriphosphazenes (NTFCPn). The hyper-cross-linked NTFCPn displayed certain porous structure and large specific surface area which benefit to the electrochemical performance of derived carbon materials. The structure and electrochemical properties of multi-heteroatom-doped porous carbons were optimized by adjusting the side group ratio of NTFCP and the carbonization temperature. The obtained carbon material cNTFCP65-600 possessed a large specific surface area up to 2006 m2/g with high proportion of mesopores (25%). Meanwhile, the synergistic effects of improved surface wettability and rich active sites by oxygen, nitrogen, and phosphorous doping rendered the cNTFCP65-600 with excellent electrochemical performance. In the two-electrode system, cNTFCP65-600 with a nitrogen content of 4.82% exhibited high specific capacitance of 412 F/g at the current density of 0.1 A/g, and maintained 264 F/g at current density of 20 A/g. [ABSTRACT FROM AUTHOR]

This study investigates the effects of weak intermolecular interactions on the flame retardancy of a poly(ethylene terephthalate) (PET) and polyphosphazene flame retardant. Monodispersed poly‐(cyclotriphosphazene‐co‐4,4′‐sulfonyldiphenol) (PZS) microspheres with different diameters were synthesized by controlling the reactant concentration. Simulation studies revealed that the weak intermolecular interactions between PZS and PET predominantly include strong hydrogen bonding and π–π interactions. The weak intermolecular interactions imparted high thermal stability, even in the molten state, and PZS microspheres with smaller diameters achieved stronger hydrogen bonds and π–π interactions with PET. The diameter of the PZS microspheres influenced the limiting oxygen index value and UL‐94 rating. Increasing the carbon residue alone was insufficient to promote the flame retardancy, and the weak intermolecular interactions played an important role. Thus, stronger weak‐intermolecular‐interactions are beneficial for realizing a material with superior flame retardancy and anti‐dropping performance. [ABSTRACT FROM AUTHOR]

A series of novel crosslinked polyphosphazene-aromatic ether organic–inorganic hybrid microspheres with different structures were prepared via precipitation polycondensation between hexachlorocyclotriphosphazene (HCCP) and bisphenol monomers. The bisphenol monomers have different numbers of –CF3 in the side group, which correspond to distinct oligomeric species-absorbing mechanisms. The wetting behavior of the microsphere surface was evaluated using a water contact angle (CA) measurement, which increased with the increase in the content of –CF3 in polyphosphazene. We also investigated the effects of HCCP concentration and ultrasonic power on the morphology of the microspheres. [ABSTRACT FROM AUTHOR]

• A novel hierarchical core-shell architectured fire retardant MH@CPZN is validated via a chemically guilding assembly. • The addition of MH@CPZN fire retardant significantly enhances the fire retardancy of SBS asphalt. • Flame-retardant mechanism is revealed from both the condensed and gas phases. • MH@CPZN considerably improves the high-temperature deformation resistance of SBS asphalt. Asphalt pavements are extensively utilized in tunnel pavement owing to comfortable driving, low noise, short-time construction, and simple maintenance. However, asphalt is a flammable material. To enhance fire retardancy of styrene-butadiene-styrene asphalt (SBSA) and its mixture with a preserved pavement performance, a novel hierarchical core-shell architectured fire retardant, cyclic cross-linked polyphosphazene-functionalized magnesium hydroxide (MH@CPZN), was validated via a chemically guilding assembly in this study. The fire retardancy and smoke suppression properties of SBSA containing MH@CPZN were found to be significantly improved.The MH@CPZN (10 wt%)-incorporated SBSA presented a remarkably higher limiting oxygen index (LOI) of 27.4 % relative to 21.5 % of SBSA with MH and 19.8 % of neat SBSA. In parallel, cone calorimeter test results showed that the peak heat release, peak smoke production rate and CO production of SBSA after an inclusion of 10 wt% MH@CPZN were reduced by 40 %, 35 % and 27 %, respectively, with a 20 s delayed ignition time. A large-scale fire test of asphalt mixture revealed a significant suppression of flame propagation after an addition of MH@CPZN. Moreover, the char yield at 800 °C was significantly increased to 24.1 wt% relative to 14.1 wt% of neat SBSA. A comprehensive analysis demonstrated a co-existence of multi-scale optimization of char microstructure in the condensed and radical quenching due to an interface-located polyphosphazene. Additionally, the high-temperature deformation resistance of SBSA was effectively enhanced after the incorporation of MH@CPZN. In perspective, a hierarchical assembly based on polyphosphazene and metal hydroxides exploits a facile yet practical route for multifunctionally reinforcing asphalt and its mixture with well-preserved fire retardant and pavement performance. [ABSTRACT FROM AUTHOR]

[Display omitted] Hydrogels are soft 3D materials that absorb and retain a high amount of water but don't dissolve in it. Bio-adhesives demonstrate great development in the biomedical domain for hemostatic sealing, injured skin regeneration, wound closure, and protecting bio-devices from bio-tissue. These properties render them remarkable future application prospects. Moreover, adhesive hydrogels support wound treatment and management due to their capability of absorbing and retaining a high quantity of water in their 3D network structure, maintaining the wet environment around the wounded sphere, and acting like a natural extracellular matrix. Furthermore, wound dressings are highly applied to support wound treatment, and the conventional method of dressing requires a tape fixation on the traumatic site which is inappropriate within the human body. The internal injury is treated via direct suture which leads to secondary damage to the patient and enhances the infection risk. The adhesive with high adhesive forces integrates with the internal and external wounds firmly and forms a barrier for the prevention of bacterial invasion, enhances the healing process, and prevents suture-caused secondary damage but the presence of fluids such as water and blood on the wound surfaces makes the adhesive hydrogel unfit for wound treatment. Therefore, it is mandatory to achieve robust adhesion in a wet environment. The fabrication of wet adhesive hydrogel with greater adhesion and remarkable biocompatibility has become an imperative current research topic therefore; this review focuses on currently fabricated tissue adhesive hydrogels based on chitosan, phenylboronic acid, catechol, polyphosphazene, hyaluronic acid, starch, and cellulose. This paper also focuses on the wet surface adhesive, anti-bacterial, and self-healing properties of adhesive hydrogels as well as applications of adhesive hydrogels for wound and bone treatment. [ABSTRACT FROM AUTHOR]

Arone-containing cyclomatrix-type polyphosphazene hybrid microspheres (PZK) were synthesized to enhance both the fire safety and mechanical performance of epoxy resin (EP). The chemical structure and micro-morphology of PZK were characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy, and X-ray photoelectron spectroscopy. Subsequently, PZK was employed in fabricating EP thermosets. Thermal properties of the PZK modified EP thermosets were comprehensively assessed through thermalgravimetric analysis (TGA) and dynamic mechanical analysis. The results indicate that PZK endowed EP with enhanced char yield and storage modulus, attributed to its exceptional thermal stability and distinctive microsphere structure. Additionally, with only a 1.5% loading of PZK, EP achieved a UL-94 V-1 rating during vertical flame testing, accompanied by an increased limiting oxygen index of 28.3%. Additional analysis with a cone calorimeter demonstrated that the addition of PZK markedly reduced the peak heat release rate, total heat release, fire growth rate, and total smoke production of EP, indicating notable efficacy in suppressing heat and smoke release. Char residue and pyrolysis products were analyzed using SEM, TG-FTIR, and pyrolysis gas chromatography-mass spectrometry, revealing that PZK effectively inhibits the release of combustible gases from EP during thermal decomposition. The expected generation of Ph—O• radicals from arone units in PZK suggested a gaseous free radical trapping mechanism. The phosphazene framework played a crucial role in forming condensed-phase char due to its exceptional thermal stability. Consequently, PZK exhibited a typical biphasic flame-retardant mechanism for EP. Notably, the study observed that the introduction of PZK simultaneously enhances the tensile strength, flexural strength, and modulus of EP, with a particularly significant improvement observed in impact strength. This research expands the scope of investigation into the preparation and flame-retardant application of cyclomatrix-type polyphosphazene hybrid microspheres in polymers. [Display omitted] [ABSTRACT FROM AUTHOR]

• Natural polyphenol conjugated prodrug hydrogels were designed for prevention of peritendinous adhesion. • The prodrug strategy using ROS-responsive bridging linker exhibited targeted aggregation toward the high ROS region. • The hydrogel could reduce the clinical adhesion scores of peritendinous adhesion by 3–4 grades. The bidirectional regulations of antiadhesion and regeneration are crucial for Achilles tendon injuries. However, the precise prevention and treatments of peritendinous adhesions both in time and space are still great challenges. Here, a series of time–space regulating prodrug (tannic acid (TA), epigallocatechin (EGC) and epigallocatechin gallate (EGCG)) hydrogels are designed for the prevention of peritendinous adhesion in Achilles tendon contusion and rupture injuries. In the term of space, the self-healing and deformable hydrogels prepared by crosslinking phenylboric acid (PBA) functionalized polyphosphazene (PZBA) with guar gum (GG) through ROS-responsive phenylborate ester (PBAE) can specifically aggregate to the high ROS sites via the ROS-responsive degradation and recombination of PBAE. Thus, providing support and acting as barriers to inhibit fibroblast proliferation. In the term of time, the prodrug strategy using ROS-responsive PBAE as bridging linker can achieve long-term anti-inflammatory effect over 2 weeks. Furthermore, the degradation time of hydrogels matched the course of peritendinous adhesion, thus achieved bidirectional regulations (decrease the gene expression of TGF-β1, COL-1 and COL-3 to antiadhesion in the early stage but increase them to promote regeneration in the late stage). This study presents a promising approach employing smart prodrug hydrogels with time–space regulating properties for prevention of peritendinous adhesion. [ABSTRACT FROM AUTHOR]

The main chain of the inorganic polymer polyphosphazene exhibits good alkaline stability, but its poor film-forming properties and excessive water uptake have led to its limited application in the field of anion exchange membranes. In this study, naphthol-substituted polyphosphazene anion exchange membranes demonstrate good film-forming properties and conductivity. When the degree of naphthol substitution reaches around 33%, the hydrophobic main chain and hydrophilic side chain can form a well-defined hydrophilic and hydrophobic phase separation structure. Its ionic conductivity can reach 59.1 mS cm−1 at 80 °C, with a swelling ratio of only 23.5%. Observation under atomic force microscopy reveals that this is due to the introduction of naphthol, which enhances the π-π stacking effect between the main chains, forming a more stable hydrophobic region. Furthermore, when exposed to 4 mol L−1 NaOH at 80 °C for 1000 h, the ionic conductivity of NapP2N-4 decreased by only 19%, and the elongation at break did not significantly decrease, reflecting its good alkaline stability. • Synthesized a multisubstituted polyphosphazene anion exchange membrane. • Quaternary ammonium polyphosphazenes with naphthol substitution have good phase separation structure. • Effectively enhancing polysubstituted polyphosphazenes with naphthol substituted groups. [ABSTRACT FROM AUTHOR]

In this paper, a sequence of polyphosphazenes (PPZs) as electrochromic (EC) and sensor materials have been designed and synthesized by introducing chromophores, (4-(diphenyl amino)phenyl) methanol (CH1) for PPZ1, 3-(4-(dimethyl amino) phenyl)-2-(4hydroxyphenyl) acrylonitrile (CH2) for PPZ2, and CH1 and CH2 for PPZ3 into the main chain. In terms of EC performance, PPZ1 shows the best EC performance among the three PPZs which can achieve 60 % optical contrast at 690 nm with good cyclic stability within 1000 s and fast switching response time (t color/ t bleach = 1.2 s/0.6 s). Compared to PPZ1, the oxidation potential of PPZ3 is reduced compared to PPZ1. PPZ2 and PPZ3 as sensors are more sensitive for the detection of 2,4,6-trinitrophenol (TNP) and trifluoroacetic acid (TFA) compared to PPZ1. What's more, PPZs can be used in memory devices with non-volatile flash memory performance and switching current ratios of 103:102.4:1, 104.7:101.3:1 and 103.5.:100.6:1 respectively. Therefore, PPZs have the promising prospect in optoelectronic field. [Display omitted] • Three multifunctional PPZs grafted with various chromophores were designed and synthesized. • PPZ3 has decreased oxidation potential. • PPZ2 & PPZ3 exhibit higher sensitivity in detecting TNP & TFA. • PPZs show good memory storage properties. [ABSTRACT FROM AUTHOR]

Common flame retardants, such as halogen-based materials, are being phased-out owing to their harmful environmental and health effects. We prepared poly-(cyclotriphosphazene-co-4,4′-sulfonyldiphenol) (PZS) microspheres, nanotubes, capsicum-like nanotubes, and branched nanotubes as flame retardants. An increase in reaction temperature changed the morphology from nanotubes to microspheres. A PZS shape had a positive effect on the flame retardancy of polyethylene terephthalate (PET). The PZS with a capsicum-like nanotube morphology had the best flame retardancy, and the PET limiting oxygen index increased from 25.2% to 34.4%. The flame retardancy capability was followed by PZS microspheres (33.1%), branched nanotubes (32.8%), and nanotubes (32.5%). The capsicum-like nanotubes promote the formation of highly dense and continuous carbon layers, and they release a non-combustible gas (CO2). This study confirms polyphosphazene-based flame retardants as viable and environmentally-friendly alternatives to common flame retardants. It also presents a novel and facile design and synthesis of morphology-controlled nanomaterials with enhanced flame retardant properties. [ABSTRACT FROM AUTHOR]

In this study, it is aimed to investigate in vitro pH-responsive, dual anticancer drug release from cyclomatrix polyphosphazene nanospheres for combination chemotherapy. For the first time, novel cyclomatrix polyphoshazene nanospheres that contain curcumin and quercetin were prepared by one-pot drug self-framed precipitation polymerization. Curcumin and quercetin were used both as monomers in synthesis of nanospheres and as released drugs. The nanospheres were characterized by SEM, EDX, FTIR, solid state 31P-NMR, BET, XRD, DLS and UV–vis techniques. It was determined that nanospheres contained 500 mg.g−1 drugs (DL%: 36% curcumin, 14% quercetin; EE%: 47.2% curcumin and 23% quercetin). The controlled release of drugs was investigated in lysosomal pH (pH:5.5) and blood pH (pH:7.4), at 37 °C, using dialysis membrane. Quercetin and curcumin were released from nanospheres at pH 7.4: 18.14%, 2.25%; pH 5.5: 10.12%, 1.02%, respectively, at 7 days. The release kinetic was determined to be Korsmeyer-Peppas kinetic model according to correlation coefficients, and the release mechanism was non-Fickian model for nanospheres. [ABSTRACT FROM AUTHOR]

A poly (cyclotriphosphazene‐resveratrol) (PRS) microsphere was synthesized via a feasible in‐situ template approach and applied to poly (ethylene terephthalate) (PET) for ameliorating its flammable and melt‐dropping issues. The prepared PRS microspheres displayed superior thermal stability and flame retardancy. By incorporating only 2 wt% of PRS microspheres into PET matrix, the limiting oxygen index value was increased from 23.3% to 28.3% and reached the UL‐94 V‐0 level without any after‐flame time. Cone calorimeter test demonstrated that the HRR and THR of PET/FR2.0 composite decreased significantly by 31.1% and 13.5%, respectively, which remarkably increased the fire safety of PET. On the other hand, the tensile strength and elongation at break of PET/FR2.0 composite decreased slightly, whereas the tensile modulus was increased by 10.5% than that of the pure PET. Moreover, the fire‐retardant mechanism of PRS microspheres was fully investigated, revealing that PET/FR system would generate compact and continuous char layers rapidly during combustion, the underlay materials would not be further cracked due to the isolation of external heat and oxygen. Nonflammable gases such as ammonia were also released to dilute the concentration of combustible gases around the PET matrix, achieving an efficient flame retardant effect. [ABSTRACT FROM AUTHOR]

Use of Salen‐phosphazene (Salen‐PZN) complex for flame retardant polymeric materials demonstrate good flame retardancy due to their abundant flame retardant elements and aromatic‐rich structure. To further enhance their flame retardancy and interaction with the matrix, phosphorous (DK) was armed on nickel‐based Salen‐polyphosphazene complex (DK@Salen‐PZN‐Ni) as a smart decoration. The composite with DK decoration has higher tensile strength than the DK‐free composite. Moreover, cone calorimeter study showed that with 3 wt% total additive loading, the peak heat release rate (pHRR) and peak smoke rate (pSPR) of DK@Salen‐PZN‐Ni/EP composite were reduced by 21.0% and 30.3%, respectively when compared with pure EP. The limited oxygen index of the composite was 30.2%, while the vertical burning test (UL‐94) reached the V‐1 rate. Flame retardance mechanism of DK@Salen‐PZN‐Ni was discussed in detail. The designing of flame retardants alleviated the mechanical property failure and improved the flame retardancy of polymeric composite. [ABSTRACT FROM AUTHOR]

Novel, eco‐friendly, and halogen‐free polyphosphazene‐based flame retardant (FR) cathodes for Li–S batteries are prepared by the inverse vulcanization of elemental sulfur with polybis(2‐acrylamidoethoxy)phosphazene (poly(AAE)) resulting in the covalently bonded different wt% sulfur content polymers. Due to the polar amide groups, poly(AAE)‐xS (x refer to the wt% of sulfur) composites assist in anchoring intermediate lithium polysulfide species. The structural characterizations of the poly(AAE)‐xS polymers are conducted by elemental analysis, Fourier‐transform infrared spectroscopy, differential scanning calorimeter, thermogravimetric analysis, and scanning electron microscopy. Their FR properties are elevated by calculation of the limiting oxygen index values and burning tests. Later, lithium‐ion storage mechanism of poly(AAE)‐55S polymer is evaluated, including cyclic voltammetry, rate performance tests and electrochemical impedance spectroscopy measurements. To compare with the electrochemical performance of poly(AAE)‐55S, a noncovalent blend polymer mixture and bare sulfur are also tested. It is found that covalently bonded poly(AAE)‐55S obtained by the inverse vulcanization of elemental sulfur and poly(AAE) results much pronounced capacities. Herein, new insights into the design and development of alternative cathode materials for safer Li–S batteries, both providing FR properties and good lithium polysulfides adsorption capabilities, are offered. [ABSTRACT FROM AUTHOR]

We explored a facile method for grafting bi-functional groups terminated branched polyphosphazene on carbon fibers via direct epoxy amination with an aqueous ammonia solution. The branched polyphosphazene with abundant β-hydroxyl groups and amino groups significantly changes the chemical composition of carbon fibers surface. A significant improvement in interfacial shear strength was obtained from 43.6 MPa for virgin carbon fibers (C.F.) composites to 89.6 MPa for branched polyphosphazene grafted C.F. composites.

Basavaraj R Patil,1 Su Yeon Kang,2 Da Hee Jung,2 Prakash G Avaji,1 Yong Joo Jun,1 Hwa Jeong Lee,2 Youn Soo Sohn1 1C & Pharm, Ewha Womans University, Seoul 03760, Republic of Korea; 2Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 03760, Republic of KoreaCorrespondence: Youn Soo SohnC & Pharm, Ewha Womans University, Room 304, University-Industry Cooperation Building, 52 Ewhayeodae-Gil, Seodaemun-Gu, Seoul 03760, Republic of KoreaTel +82 70 7008 2120Fax +82 2 362 8813Email yssohn@ewha.ac.krHwa Jeong LeeGraduate School of Pharmaceutical Sciences, Ewha Womans University, 52 Ewhayeodae-Gil, Seodaemun-Gu, Seoul 03760, Republic of KoreaTel +82 2 3277 3409Fax +82 2 3277 2851Email hwalee@ewha.ac.krPurpose: A new theranostic nanomedicine involving anticancer-active cisplatin moiety was designed to study its tumor-targeting properties as well as its drug efficacy and toxicity.Methods: A cisplatin carrier polymer was prepared by grafting equimolar polyethylene glycol of a molecular weight of 550 (PEG550) and aminoethanol to the poly(dichlorophosphazene) backbone. Cisplatin was conjugated to the carrier polymer using cis-aconitic acid as a linker.Results: The cisplatin-loaded polyphosphazene, named “Polycisplatin” was found to be amphiphilic in aqueous solution and self-assembled into nanoparticles with an average particle size of 18.6 nm in diameter. The time-dependent organ distribution study of Cy5.5-labeled Polycisplatin in the A549-tumor-bearing mice exhibited a high tumor selectivity of Polycisplatin by EPR effect despite the relatively small particle size. In order to compare the in vivo efficacy of Polycisplatin and cisplatin, their xenograft trials were performed using nude mice against the human gastric cell line MKN-28. Polycisplatin exhibited slightly less tumor suppression effect compared with cisplatin at the same dose of 1.95 mg Pt/kg, which is the maximum tolerate dose of cisplatin, but at the higher double dose of 3.9 mg Pt/kg, Polycisplatin exhibited a little better efficacy than cisplatin. Furthermore, mice treated with cisplatin at the dose of 1.95 mg Pt/kg exhibited severe body weight decrease by about 25%, while mice treated with Polycisplatin did not show serious body weight decrease even at its double dose of 3.9 mg Pt/kg. Furthermore, kidney indicators including kidney index, BUN, and creatinine values measured displayed that Polycisplatin is much less nephrotoxic than cisplatin.Conclusion: Nanoparticular Polycisplatin was successfully prepared by conjugating cisplatin to a hydrophilic polyphosphazene carrier polymer using the acid-cleavable cis-aconitic acid. Polycisplatin nanoparticles exhibit excellent tumor-targeting properties by EPR effect. The xenograft trials exhibited excellent antitumor efficacy and reduced systemic toxicity of Polycisplatin.Keywords: cisplatin, polyphosphazene, platinum drug, drug delivery, nanomedicine

Alloy-type antimony (Sb) and conversion-type molybdenum (Mo) anodes have attracted extensive attention in the application of lithium-ion batteries (LIBs) owing to their high theoretical capacity. In this study, Sb 2 MoO 6 nanowires are prepared via a hydrothermal method and assessed their thermal behavior upon heat treatment, observing an intriguing transformation from nanowire to Sb 2 O 3 /MoO x nanosheets. To enhance structure stability, the Sb 2 MoO 6 nanowires are successfully coated with a polyphosphazene layer (referred to as PZS@Sb 2 MoO 6 ), which not only preserved the nanowires form but also yielded N/S co-doped carbon-coated SbPO 4 /MoO x (NS-C@SbPO 4 /MoO x ) nanowires following annealing in an inert environment. This composite benefits from the stable PO 4 3- anion that serve as a buffer against volume expansion and form a Li 3 PO 4 matrix during cycling, both of which substantially bolster ion transport and cycle endurance. Doping with heteroatoms introduces numerous oxygen vacancies, augmenting the number of electrochemically active sites, and carbon integration considerably enhances the electronic conductivity of the electrode and alleviates the volume-change-induced electrode pulverization. Employed as anode materials in LIBs, the NS-C@SbPO 4 /MoO x electrode exhibits remarkable cycling performance (449.8 mA h g -1  at 1000 mA g -1 over 700 cycles) along with superior rate capability (394.2 mA h g -1 at 2000 mA g -1 )., (© 2024 Wiley‐VCH GmbH.)