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Nowadays, reducing the fire hazard of thermoplastic polyurethane (TPU) is an important research direction in the fields of fire safety materials. In this article, hollow glass microsphere (HGM) was used to reduce the fire hazard of TPU in combustion process. The fire characteristics including smoke and heat production of TPU composites were evaluated using smoke density test (SDT) and cone calorimeter test (CCT). And the thermal decomposition and flammable properties were further studied using thermogravimetric analysis/infrared spectrometry (TG-IR) and limiting oxygen index (LOI), etc. The SDT results showed that the luminous flux (LF) of TPU4 containing 2.00 wt% HGM was up to 24% at the end of test without flame, which is much higher than that of TPU0 (5%). And, the CCT results indicated that 2.00 wt% HGM could make the total smoke release (TSR) decrease from 1019 m 2 /m 2 (TPU0) to 757 m 2 /m 2 (TPU4), reduced by 26%. The TG-IR results confirmed that HGM could improve the thermal stability of composites and reduce the production of some toxic gases. The above results illustrated HGM had a good prospect in reducing the fire hazard for TPU. [ABSTRACT FROM AUTHOR]

Abstract: Melamine salt of pentaerythriol phosphate (MPP), as a new single molecule intumescent flame-retardant, was prepared from pentaerythritol, phosphoric acid, and melamine, and then incorporated into polypropylene (PP) with organic montmorillonite (OMT) to obtain flame retardant PP/MPP/OMT composites. The flammability and combustion behavior of flame retardant PP composites were characterized by using LOI, UL-94 test, and cone calorimeter, respectively. The results showed that the flame retardant properties of the composite containing 29.0wt% MPP and 1.0wt% OMT are the best among all the composites. The digital photographs after cone calorimeter test demonstrated that moderate OMT could promote to form the homogenous and compact intumescent char layer. [Copyright &y& Elsevier]

Abstract: The effects of hydroxy silicone oil (HSO) as a synergistic agent on the flame retardancy of intumescent flame retardant polypropylene composites (IFR-PP) were studied, and the IFR system mainly consisted of the ammonium polyphosphate (APP) and pentaerythritol (PER). The UL-94 test, thermogravimetric analysis (TGA), cone calorimeter (CONE), digital photograph and X-ray photoelectron spectroscopy (XPS) were used to evaluate the synergistic effects of hydroxy silicone oil. It has been found that the Polypropylene (PP) composite containing only APP and PER does not show good flame retardancy at 30% additive level. The cone calorimeter results show that the heat release rate, mass, total heat release, carbon monoxide and carbon dioxide of PP/APP/PER/HSO composites decrease in comparison with the PP/APP/PER ternary composite. The digital photographs demonstrated that HSO could promote to form the homogenous and compact intumescent char layer. Thus, a suitable amount of HSO plays a synergistic effect in the flame retardancy. [Copyright &y& Elsevier]

Abstract: A novel phosphate acrylate monomer (TGMAP) has been synthesized by allowing phosphoric acid to react with glycidyl methacrylate. Its structure was characterized by Fourier transformed infrared spectroscopy (FTIR) and 1H nuclear magnetic resonance spectroscopy (1H NMR). The thermal degradation mechanism was characterized using thermogravimetric analysis/infrared spectrometry (TG-IR). The char yield was 36.3% at 600 °C. TG data indicate that the material undergoes degradation in three characteristic temperature stages, which can be attributed to the decomposition of the phosphate, thermal pyrolysis of aliphatic chains, and degradation of an unstable structure in char, respectively. The volatilized products formed on thermal degradation of TGMAP indicated that the volatilized products are CO, CO2, carboxylic acid, acid anhydride, water, alkane, and aromatic compounds according to the temperature of onset formation. [Copyright &y& Elsevier]

Abstract: Halogen-free flame retarded ethylene vinyl acetate copolymer (EVA) composites using Mg-Al-CO3 hydrotalcite (MALDH) and microcapsulated red phosphorus (MRP) have been prepared in a melt process. The flame retardation of the composites has been studied by the limited oxygen index (LOI) and UL-94 methods, and the thermal decomposition by the thermogravimetric analysis (TGA). The changes of their properties of the composites before and after the Gamma irradiation are compared. The synergistic effect in the flame retardation between MALDH and MRP in EVA has been found. The EVA/MALDH/MRP composites after the irradiation crosslinking result in a great increase in the Vicat softening point. The LOI value, the mechanical properties and thermal stability are also improved for the composites irradiated by a suitable irradiation dose. [Copyright &y& Elsevier]

Abstract: Vinyl trimethoxysilane (VTMS) and vinyl triethoxysilane (VTES) grafted ethylene–octene copolymer (POE) were prepared in the melt process. The effects of silane concentration, reaction time and temperature on the silane grafting were investigated, and the grafting reaction was in situ monitored using the differential scanning calorimetry (DSC). The silane grafted POE was characterized by the Fourier transform infrared spectroscopy (FTIR) and melt flow index (MFI). MFI data of the silane grafted POE show that the MFI value is affected not only by DCP concentration, but also by silane concentration. The difference of gel content between VTMS and VTES crosslinked POE indicates that for POE, the grafting reaction activity of VTES is higher than that of VTMS. Moreover, the thermal behavior and mechanical properties of the crosslinked POE were also studied. It has been found that the thermal stability and mechanical properties of the silane crosslinked POE are greatly improved. [Copyright &y& Elsevier]

The non-isothermal crystallization kinetics of silane crosslinked polyethylene (SXPE) and dicumyl peroxide (DCP) modified polyethylene (DMPE) were studied by differential scanning calorimetry at different cooling rates. Three methods, namely, the Avrami, the Ozawa, and the Mo, were applied to describe the crystallization process of virgin LLDPE, DMPE and SXPE under non-isothermal conditions. The values of half-time of crystallization t1/2, and the parameter Zc in the Avrami method which characterize the kinetics of non-isothermal crystallization, show that the crystallization rates of virgin LLDPE and DMPE are faster than that of SXPE at the same cooling rate, and crystallization rates of all samples increase as the cooling rate increases. The Ozawa model is also suitable to describe the process of the non-isothermal crystallization kinetics of all samples. In the Mo method, it has been found that the F(T) values of virgin LLDPE and DMPE are lower than that of SXPE, meaning that the crystallization rate of virgin LLDPE and DMPE is faster than that of SXPE. [Copyright &y& Elsevier]

The application of fibers is more and more extensive, and the pollution caused by abandoned fibers is getting more serious, which has aroused wide attention. So it is necessary to find a way to solve the problem. In this paper, the para-aramid fiber (AF) was recycled and modified by phosphoric acid, and then was applied as environmental friendly flame retardant for thermoplastic polyurethane elastomer (TPU). The flame retardant properties of TPU were tested using cone calorimeter test (CCT) and thermogravimetric/Fourier transform infrared spectroscopy (TG-IR). The CCT test showed that AF-P had better flame retardant effect on TPU than pure AF. Remarkably, the pHRR value for the sample with 1.00 wt% content of AF-P was decreased by 48.1%; AF-P had improved the char forming progress and the residual mass was 30.6%, which was much more than pure TPU. TG test showed that AF-P could improve the thermal stability of TPU at high temperature. The TG-IR test revealed that AF-P had reduced the release of CO 2 at the beginning. Based on the above results, it will make a great influence on the study of reuse of fibers and environmental friendly flame retardant of polymer. [ABSTRACT FROM AUTHOR]

This article mainly studies synergistic flame retardant effects and smoke suppression properties of iron-graphene (IG) and aluminum hypophosphite (AHP) on thermoplastic polyurethane (TPU), AHP used as main flame retardants and IG used as synergistic agents. A high concentration of TPU/IG masterbatch was prepared by solution-blending method, and then TPU/AHP/IG composites were prepared by melt-blending method. Then, the flame retardant effects of all TPU composites were tested using limiting oxygen index (LOI), UL 94 test, cone calorimeter test (CCT), scanning electron microscopy (SEM), thermogravimetric analysis (TG) and thermogravimetric/fourier transform infrared spectroscopy (TG-IR). Remarkably, with 0.25 wt% content of IG and 9.75 wt% content of AHP, sample reached UL 94 V-0 rating, and the LOI value increased by 31.5 vol%, pHRR value decreased by 90% and pSPR value decreased by 72%, etc. SEM images show that char residues become more complete and present lamellar structure. TG-IR data reveal that the incorporation of AHP and IG promoted the release of H 2 O and CO 2 , meanwhile reduced harmful gases release. [ABSTRACT FROM AUTHOR]

• A nanohybrid with core-shell 3D cross-heterostructure, ZIF-67H@PBA, was synthesized. • Adding just 0.5wt% of ZIF-67H@PBA can effectively enhance flame retardant of TPU. • Cone calorimeter-Smoke sampling device-GCMS was constructed to show smoke release. • ZIF-67H@PBA showed high fire safe performance by catalyzing the carbonization of TPU. Thermoplastic polyurethane (TPU) has an extensive application in many different industries. However, serious fire hazards and smoke toxicity have been the main reason limiting its wide application. Therefore, it is necessary and urgent to perform flame retardant and smoke suppression treatment for TPU. In recent years, metal-organic framework compounds (MOFs) have very promising application prospects in the fields of flame-retardant polymer composites. However, there is a problem of low flame-retardant efficiency for the original MOFs alone in polymer composites. It is reported the multi-level and multi-structured flame-retardant system has better flame-retardant efficiency than the traditional structures. So, the dual MOF core-shell heterostructure may have more effective heat reduction and smoke suppression than any single component. In this paper, a core-shell 3D cross-heterostructures nanohybrid (ZIF-67H@PBA) was prepared using ZIF-67H as the host MOF and Prussian blue nanocubes (PBA) as the guest MOF. It has been found that TPU/ZIF-67H@PBA composites with ultra-low additions have excellent fire safety. Compared with those of pure TPU, the peak heat release rate (PHRR), total smoke release (TSP), and smoke factor (SF) of the samples with 0.5wt% ZIF-67H@PBA were reduced by 33.6 %, 47 %, and 61 %, respectively. At the same time, a cone calorimeter (CCT), a homemade soot sampling device and a gas chromatography-mass spectrometry (GC–MS) coupling with each other were constructed and used to demonstrate the most realistic effects of flame retardants in terms of smoke suppression and toxicity reduction. This work provides a new strategy to design TPU flame retardants. [Display omitted] [ABSTRACT FROM AUTHOR]

• A novel 3D cross-shaped ZIF-67 (ZIF-67 H) was designed. • ZIF-67 H provides TPUs with great flame retardancy and smoke suppression properties. • The catalytic flame retardancy mechanism of ZIF-67 H was summarized and speculated. Zeolite imidazolium frameworks (ZIFs), as a subcategory of metal-organic frameworks (MOFs), are widely used in many fields. And, the physical morphology, particle size, and shape of ZIFs have an important influence on their application performance, such as flame retardancy for polymer. Here, three types of ZIF-67 were prepared with different physical morphology structures including dodecahedron (ZIF-67), cube (ZIF-67 NC), and cross-shaped (ZIF-67 H), by adjusting the proportion between 2-methylimidazole and cobalt (Ⅱ) nitrate hexahydrate together with the suitable amount of surfactant (CTAB), and they were used to enhance the flame retardancy and smoke suppressing properties of thermoplastic polyurethane (TPU). It has been found the novel ZIF-67 H with 3D cross-shaped superior catalytic and flame-retardant capabilities than the other two during the burning process of TPU composites. Compared with those of pure TPU, the peak heat release rate (pHRR), total smoke production (TSP), and smoke factor (SF) of TPU/2 wt%ZIF-67 H were decreased by 45.4 %, 50.2 %, and 72.9 %, respectively. At the same time, both TPU/1 wt%ZIF-67 H and TPU/2 wt%ZIF-67 H samples showed stronger tensile properties than pure TPU at the same elongation. This work further enriches the study of multi-structured ZIFs for flame retardant TPU. [Display omitted] [ABSTRACT FROM AUTHOR]

The wide application of flexible polyurethane foam (FPUF) poses a giant challenge to human society in terms of fire prevention and environmental pollution. To solve this problem, the lignocellulose-based P–N flame retardant (LFPN) has been developed using mechanochemical methods. It was found that FPUF treated using LFPN exhibited good flame retardancy, but suffered from high smoke generation and toxicity. The hollow dodecahedral ZIF-67 has been used for smoke suppression catalysis, but the agglomeration phenomenon makes it inefficient. Hence, in this study, the adhesive properties of polydopamine (PDA) were utilized to assist the in-situ growth of ZIF-67. The results showed that the total smoke release rate of the treated FPUF was reduced by 40.5%. The toxic gases, such as carbon monoxide (CO), hydrogen cyanide, etc., also showed the same decreasing trend. What's more, the catalytic effect of ZIF-67 itself and the synergistic effect with LFPN gave FPUF great flame retardant and smoke inhibition properties. This novel FPUF provides a new reference for achieving smoke suppression and toxicity reduction. [Display omitted] • A novel Bio-based P–N synergistic (LFPN) flame retardant was developed via a mechanochemistry strategy. • In-situ growth of ZIF-67 was carried out on the LFPN surface by polydopamine (PDA). • LFPN@PDA@MOF endows FPUF with efficient flame retardancy and smoke suppression. • The flame-retardant mechanism of LFPN@PDA@MOF includes both catalysis and inhibition. [ABSTRACT FROM AUTHOR]

Abstract: Flame retardant polylactide (PLA) composites were prepared using PLA and a hyperbranched polyphosphate ester (HPE). The flammability and thermal stability of flame retardant PLA composites were investigated by limiting oxygen index (LOI), UL-94 vertical burning, microscale combustion calorimetry (MCC), and thermogravimetric analysis/infrared spectrometry (TG-IR). The results showed that HPE had excellent flame retardant abilities for PLA. The TGA curves suggested that HPE has good ability of char formation, hence improved the flame retardant property. The volatilized products formed on thermal degradation of flame retardant PLA indicated that the volatilized products are mainly aldehyde containing compounds, CO, aliphatic esters, and CO2. [Copyright &y& Elsevier]

Abstract: A novel silicone and phosphate modified acrylate (DGTH) was synthesized and characterized by 1H NMR and FTIR. It was found that DGTH could be cured both by UV radiation and moisture mode with FTIR. The flammability and thermal behavior of the cured film were studied by the limited oxygen index (LOI), thermogravimetric analysis (TG) and real time Fourier transform infrared (RT-FTIR). The LOI value of the cured film is 48 and the TG data shows that the cured film has three characteristic degradation temperature regions, attributing to the decomposition of phosphate and polyurethane to alcohols and isocyanates, thermal pyrolysis of alkyl chains, and decomposition of unstable structures in char, respectively. The RT-FTIR data implies that the degraded products of phosphate form poly(phosphoric acid) further catalyse the breakage of carbonyl groups to form an intumescent char, preventing the samples from further burning. [Copyright &y& Elsevier]

Developing efficient flame-retardant MXene-based polymeric materials with enhanced mechanical properties has been a huge challenge. Herein, Prussian blue analogues (PBAs) were used to modify the surface of MXene nanosheets via an electrostatic self-assembly method to construct hierarchical MXene-based nanohybrids (MXene@PBA). Then, MXene@PBA was incorporated into the epoxy matrix to fabricate high-performance epoxy nanocomposites (EP-MXene@PBA). The study indicates that hierarchical MXene@PBA exhibits excellent dispersion performance in the epoxy matrix. Notably, MXene@PBA results in high-efficiency flame retardancy and smoke suppression for epoxy nanocomposites at ultra-low additions. What is very surprising is that only 1.0 wt% MXene@PBA can easily enhance the UL-94 rating of EP-1.0%MXene@PBA to V0. Meanwhile, the peak heat release rate (pHRR), total smoke production (TSP), and peak CO production rate (pCO) are remarkably reduced by 36.70%, 34.28%, and 43.48%, compared to those of the pristine epoxy resin, respectively. Furthermore, the 1.0 wt% MXene@PBA nanohybrids can enhance the flexural and impact strengths of EP-1.0%MXene@PBA. This work provides a feasible strategy for the creation of multifunctional MXene derivatives and their polymeric nanocomposites and holds great promise for many industrial applications. [Display omitted] • A hierarchical MXene@PBA nanohybrid has been constructed by a facile electrostatic self-assembly strategy. • 1.0 wt% of MXene@PBA allows EP to easily achieve an attractive UL-94 V0 rating. • 1.0 wt% of MXene@PBA endows EP with high-efficiency flame retardancy and smoke suppression. • 1.0 wt% of MXene@PBA improves the flexural strength and impact strength of EP. [ABSTRACT FROM AUTHOR]

• A green organic-inorganic PAbz@ZIF hybrid has been prepared. • 5.0 wt% of PAbz@ZIF allows EP to easily achieve a UL-94 rating of v0. • PAbz@ZIF hybrids endow EP with efficient flame retardancy and smoke suppression. • PAbz@ZIF hybrids improve the heat insulation performance and mechanical performance of EP. Developing sustainable bio-based flame retardants for flammable polymers has been a research trend. However, applying bio-based flame retardants to confer excellent flame retardancy, smoke suppression, and mechanical properties to polymers remains a formidable challenge. Herein, a green organic-inorganic hybrid (PAbz@ZIF) was readily prepared through a simple neutralization reaction and in-situ generation method and applied to fabricate high-performance flame-retardant epoxy coatings (EP-PAbz@ZIF). It has been shown that PAbz@ZIF hybrids can enhance the curing activity of epoxy coatings in addition to their excellent dispersibility and interfacial compatibility. In addition, the epoxy coating containing 5.0 wt% PAbz@ZIF (EP-5%PAbz@ZIF) exhibits a higher char yield (from 25.1 wt% to 31.5 wt%) in comparison to pristine epoxy resin (EP). More importantly, the PAbz@ZIF-based epoxy coatings show more efficient flame retardancy and smoke suppression compared to pristine EP. For instance, the 5.0 wt% PAbz@ZIF enables EP-5%PAbz@ZIF to obtain a satisfactory UL-94 rating of V0. Meanwhile, the peak heat release rate, total smoke production, peak CO production rate, and peak CO 2 production rate of EP-5%PAbz@ZIF are remarkably decreased by 48.6%, 20.5%, 38.6%, and 56.7%, respectively. Furthermore, EP-5%PAbz@ZIF exhibits enhanced heat insulation performance, flexural strength, and impact strength. This work offers a feasible idea for designing green organic-inorganic PAbz@ZIF hybrids and fabricating high-performance flame-retardant epoxy coatings. [Display omitted] [ABSTRACT FROM AUTHOR]

• A hierarchical MXene@PDA@CoFeOx has been constructed by a biomimetic strategy. • MXene@PDA@CoFeOx allows EP to easily achieve a UL-94 V0 rating. • MXene@PDA@CoFeOx endows EP with efficient flame retardancy and smoke suppression. • MXene@PDA@CoFeOx improves the thermal conductivity and mechanical performance of EP. Developing high-performance MXene-based polymer nanocomposites through a biomimetic method has been a research hotspot. However, it is still an intractable challenge to achieve MXene-based polymer nanocomposites with efficient fire safety, excellent thermal conductivity, and enhanced mechanical properties. Here, inspired by the adhesion of mussels, the hierarchical MXene@PDA@CoFeOx nanohybrid was fabricated by a self-assembly strategy and then employed to prepare epoxy resin (EP) nanocomposites. It has been found that MXene@PDA@CoFeOx can display excellent dispersion and interfacial compatibility in EP matrix. Thermogravimetric analysis shows that only 2.0 wt% MXene@PDA@CoFeOx results in excellent thermal stability and char yield (31.29 wt%) of EP under a nitrogen atmosphere. Combustion tests show that the 2.0 wt% MXene@PDA@CoFeOx confers efficient fire safety to EP. Remarkably, the EP-2.0%MXene@PDA@CoFeOx can obtain an attractive UL-94 rating of V0. Meanwhile, the peak heat release rate (pHRR), smoke factor (SF), and peak CO production rate (pCO) of EP-2.0%MXene@PDA@CoFeOx are dramatically decreased by 33.38%, 55.41%, and 36.84% in comparison to those of virgin EP, respectively. The efficient fire safety of EP nanocomposites is mainly attributed to the barrier effect, dilution effect, and catalytic carbonization effect of hierarchical MXene@PDA@CoFeOx. Furthermore, the MXene@PDA@CoFeOx enables EP to boast enhanced thermal conductivity (improved by 69.14%), impact strength (improved by 13.38%), and flexural strength (improved by 17.60%). This work offers a feasible biomimetic method for fabricating hierarchical MXene@PDA@CoFeOx nanohybrids and preparing efficient fire-safe EP nanocomposites with excellent thermal conductivity and mechanical performance. [Display omitted] [ABSTRACT FROM AUTHOR]

Rigid polyurethane foam (RPUF) has received extensive attention as an energy-saving building material. However, it is still a great challenge to easily fabricate multifunctional RPUFs that combine excellent mechanical properties, flame retardancy, and thermal insulation. Herein, ammonium polyphosphate was chemically modified with 2-aminobenzimidazole (APP@Abz) through an ion exchange reaction. It has been found that APP@Abz is well-dispersed in RPUF matrix. FR-RPUF3 containing 10.0 wt% of APP@Abz shows excellent thermal insulation performance with a 5% increase in thermal conductivity compared to virgin RPUF. In addition, FR-RPUF3 exhibits ultrahigh flame retardancy and smoke suppression (total heat release, total smoke production, and smoke factor decreased by 50.61%, 61.90%, and 64.70%, respectively) in comparison to virgin RPUF. More importantly, FR-RPUF3 exhibits improved mechanical properties and hydrophobicity compared to virgin RPUF. This study is of great importance for the development and application of building insulation materials. [Display omitted] • APP@Abz was synthesized as a novel flame retardant for RPUF using ammonium polyphosphate and 2-aminobenzimidazole. • APP@Abz effectively improves the thermal insulation and mechanical properties of RPUF. • APP@Abz shows high flame retardancy and smoke suppression for RPUF. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu(II) and Co(II) complexes decorated ammonium polyphosphate were prepared as co-curing agents for epoxy coatings. • Both BAPP@Cu and BAPP@Co exhibit excellent fire safety and heat insulation performance for epoxy coatings. • Both BAPP@Cu and BAPP@Co can enhance the mechanical properties of epoxy coatings. Epoxy resin (EP) is widely used as an organic coating in the field of building materials (such as steel and timber). However, it's high flammability and smoke release in fires further hinder its application in construction. Here, Cu(II) and Co(II) complexes decorated ammonium polyphosphates (BAPP@Cu and BAPP@Co) were synthesized by a facile strategy of chemical surface modification and used as multifunctional additives to enhance various properties of epoxy coatings. It has been found that both BAPP@Cu and BAPP@Co as co-curing agents not only promote the curing reaction of EP but also enhance the interfacial compatibility between the filler and the epoxy matrix. In addition, both BAPP@Cu and BAPP@Co endow EP with enhanced mechanical performance and heat insulation compared to pristine ammonium polyphosphate (APP). More importantly, both BAPP@Cu and BAPP@Co impart excellent fire safety to EP coatings. The peak heat release rate (pHRR) and peak CO production rate (pCO) of EP-6 %BAPP@Cu are decreased by 35.6% and 46.2%, respectively, compared to virgin EP. Similarly, EP-6 %BAPP@Co exhibits high fire performance, with a 57.7% reduction in pHRR and a 62.9% reduction in pCO, respectively, in comparison to virgin EP. This work reports a new strategy for the chemical modification of APP by metal complexes and provides a new perspective for the application of building coating materials. [ABSTRACT FROM AUTHOR]

• A novel flame retardant was coated on the surface of cotton fabric via a straightforward step-by-step dip-coating method. • The introduction of AEP/IL/Cu significantly solves the problem of a large number of toxic smoke gasses released from Cot/AEP/IL. • Cot/AEP/IL/Cu significantly inhibited the production of toxic smoke gasses and improved the flame-retardant and antibacterial properties of the cotton fabric greatly. To meet the demands of reducing the serious illness caused by the growth of bacteria and the severe life-threatening due to interior fabric fire, the attention to antibacterial flame-retardant cotton fabrics has reached an unprecedented height. In this work, a simple step-by-step dip-coating method was applied for the multifunctional cotton based on epichlorohydrin-modified aramid nanofibers (AEP), ionic liquid (IL), and CuSO 4. Cot/AEP/IL/Cu exhibited low flammability with a limiting oxygen index (LOI) improving from 18.5% to 28.5% and high flame retardancy (e.g., ∼43.7% and 41.7% decline in peak heat release rate (pHRR) and total heat release rate (THR)). Noticeably, the Cot/AEP/IL/Cu revealed conspicuous smoke suppression and toxic reduction property compared with Cot/AEP/IL (e.g., ∼77.0% decline in peak smoke release rate (pSPR) and 40.5% in total CO production (TCOP)). In addition, the antibacterial property of treated cotton was investigated by the agar diffusion plate method. Due to the presence of Cu ion, Cot/AEP/IL/Cu remarkably restrains the activity of E. coli and S. aureus. This work prepared a multifunctional cotton fabric integrated with flame-retardant, smoke suppression, toxicity reduction, and antibacterial in a straightforward way, which endows promising applications in many fields. [Display omitted] [ABSTRACT FROM AUTHOR]

This article mainly studied fire safety effects of para -aramid fiber (AF) in thermoplastic polyurethane (TPU). The TPU/AF composites were prepared by molten blending method, and then the fire safety effects of all TPU composites were tested using cone calorimeter test (CCT), microscale combustion colorimeter test (MCC), smoke density test (SDT), and thermogravimetric/fourier transform infrared spectroscopy (TG-IR). The CCT test showed that AF could improve the fire safety of TPU. Remarkably, the peak value of heat release rate (pHRR) and the peak value of smoke production rate (pSPR) for the sample with 1.0 wt% content of AF were decreased by 52.0% and 40.5% compared with pure TPU, respectively. The MCC test showed that the HRR value of AF-2 decreased by 27.6% compared with pure TPU. TG test showed that AF promoted the char formation in the degradation process of TPU; as a result the residual carbon was increased. The TG-IR test revealed that AF had increased the thermal stability of TPU at the beginning and reduced the release of CO 2 with the decomposition going on. Through the analysis of the results of this experiment, it will make a great influence on the study of the para -aramid fiber in the aspect of fire safety of polymer. [ABSTRACT FROM AUTHOR]

Phosphorus-containing ionic liquid derivatives have been proven to be effective flame retardants for epoxy resin (EP). Flame retardants can accelerate the curing process and improve flame retardancy and smoke suppression of EP composites, which is challenging. In this paper, a novel phosphorus-containing ionic liquid (TPP-PF 6) was synthesized and used both as a co-curing agent with 4,4′-diaminodiphenylmethane (DDM) and as a highly effective flame retardant for EP. It has been found that TPP-PF 6 was conducive to improve the char formation of EP to inhibit the smoke release at high temperatures. For EP/TPP-PF 6 composites, the flame-retardant performance was enhanced rapidly with the increase of TPP-PF 6. With only 2 wt% of TPP-PF 6 , EP/2.0TPP-PF 6 reached a UL-94 V-0 rating and a limiting oxygen index of 30.3%. The peak heat release rate, total heat release, and total smoke production values of EP/2.0TPP-PF 6 were reduced by 36.32%, 45.81%, and 15.1% compared with those of pure EP, respectively. The thermal degradation products and flame retardant mechanism in gas and condensed phases were studied. It was found that TPP-PF 6 had flame retardant effect in the barrier effect of the condensed phase and the quenching effect of the gas phase. This work explores the high-efficiency flame retardant and smoke-suppressive structures with co-curing properties for EP, thus promoting the wide application of EP materials. [Display omitted] • A phosphorus-containing ionic liquid (TPP-PF 6) was successfully synthesized. • TPP-PF 6 was used as a co-curing agent, which can endow flame retardancy and smoke suppression tp EP. • TPP-PF 6 functioned in both condensed and gas phases because of its special chemical structure. • A promising way to achieve co-curing behavior and flame retardancy was proposed. [ABSTRACT FROM AUTHOR]

In recent years, bio-based flame retardants have attracted extensive interest on account of their environmental-friendly character compared with traditional flame retardants. It is reported that oyster shell powder (OSP), composed of 95% calcium carbonate and 5 % organic matter, displays excellent flame retardant potential. In this paper, a novel bio-based flame retardant named functionalized oyster shell powder (FOSP) was prepared by mechanochemistry strategy based on OSP and ammonium polyphosphate (APP) and applied to enhance the fire safety of epoxy resin (EP) composites. The results showed that FOSP emerged with notable effects in improving the fire safety performance for EP composites. Compared with pure EP, the peak value of smoke production rate (pSPR) and peak value of heat release rate (pHRR) reduced by 69.4 % and 78.2 %, respectively. In addition, the char yields of EP composites were higher than EP. Conspicuously, the total CO production for EP composites with the addition of FOSP decreased by 44.9 % compared with EP composites with the addition of APP. Therefore, OSP, a typical marine solid waste, will become a promising candidate for high fire safety polymers. • FOSP as a novel flame retardant was synthesized via mechanochemical treatment of oyster waste. • FOSP can effectively improve the fire safety of epoxy composites. • FOSP can catalyze the formation of char residue layers and noncombustible gases during the combustion process. [ABSTRACT FROM AUTHOR]

Abstract: A series of flame retardant ethylene-vinyl acetate (EVA) composites, with different content of magnesium hydroxide (MH) and hollow glass microspheres (HGM), have been prepared. The synergistic flame retardant effects of HGM with MH in EVA/MH blends have been studied by limiting oxygen index (LOI), UL-94 tests, cone calorimeter test (CCT), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM), respectively. The LOI and UL-94 results show that when 2.00 wt% magnesium hydroxide (MH) is substituted with HGM, the LOI value can be raised to the maximum value of 42.1 among all samples. The data obtained from the CCT test indicate the heat release rate (HRR) of EVA/MH/HGM sample with 1.00 wt% HGM reduced by 37% when compared with EVA/MH sample without HGM. The digital photo graphs and scanning electron microscope (SEM) of char residues after CCT give positive evidence that the synergistic flame retardant effects between HGM and MH can be described that HGM mixed with MH can decrease the melt viscosity of EVA/MH/HGM, and promote the homogeneous dispersion of MH. HGM also can promote the formation of compact charred layers and prevent the charred layers from cracking, which effectively protects the underlying materials from burning. The TGA results reveal that EVA/MH/HGM samples show higher thermal stability at high temperature than EVA/MH sample. [Copyright &y& Elsevier]

• KH-560 acts as a bridge to connect boron nitride and ionic liquid, thus obtaining ionic liquid modified boron nitride nanosheets (BNO@IL). • Ionic liquid significantly enhances the interface interaction between boron nitride and epoxy resin. • After adding 2 wt% of BNO@IL nanosheets, the fire safety performance of epoxy resin composites is significantly enhanced compared with pure EP. Hexagonal boron nitride (h-BN) is more challenging to exfoliate into fewer layers than graphene due to the ionic bond between B and N atoms (lip-lip interaction) from adjacent layers. In this paper, boron nitride was exfoliated and hydroxylated by thermal oxidation in air. Hydroxylated boron nitride nanosheets (BNO) were modified by ionic liquids and added to epoxy resin to prepare epoxy matrix nanocomposites (EP/BNO@IL). The SEM results of EP/BNO@IL nanocomposites suggested that the introduction of ionic liquids enhanced the interfacial interaction between boron nitride nanosheets and epoxy resin (EP). Thermogravimetric (TG) results showed that introducing 2 wt% BNO@IL nanosheets improved the thermal stability of EP. In addition, cone calorimeter test (CCT) results showed that BNO@IL nanosheets enormously improved the fire safety performance of the epoxy resin. The peak heat release rate, total heat release, peak smoke release rate, and total smoke release of epoxy resin nanocomposites with 2 wt% BNO@IL nanosheets decreased significantly. In this work, the realization of ionic liquid modified boron nitride nanosheets (BNO@IL) provides new possibilities for improving the fire safety performance of EP. [ABSTRACT FROM AUTHOR]

• Phytic acid doped polyaniline-coupled g-C 3 N 4 (CP@PA) was synthesized as flame retardant for epoxy resin (EP). • CP@PA can improve the flame retardant efficiency and waterproof property of EP composites based on APP. • CP@PA could promote EP/APP to form a highly cross-linked network and char residue layer. In this study, polyaniline-coupled graphitic carbon nitride (g-C 3 N 4) doped with phytic acid (CP@PA) hybrids are prepared by an in-situ chemical oxidative method. The CP@PA and APP (Ammonium Polyphosphate) are added into epoxy resin (EP) for EP composites. The characteristic test results show that CP@PA can react with epoxy resin (EP) to promote the curing of EP. And CP@PA disperses in EP uniformly. The cone calorimetry test (CCT) results show that the pHRR, THR, and TSP of EP-8A4CP@PA (the EP sample with 8.0 wt% APP and 4.0 wt% CP@PA) reduce 85%, 76.8%, and 78.9%, respectively than EP-0 (pure EP), which are lower than any other samples. The results of the back temperature test show that EP-8A4CP@PA has better thermal insulation and flame-retardant properties than EP-12APP (the EP sample with 12.0 wt% APP). Moreover, CP@PA promotes the waterproof properties of EP with APP composites by synergizing with APP to form a labyrinth effect. After a comprehensive analysis, the fire protection mechanisms of EP-8A4CP@PA are proposed as follows. CP@PA promote EP charring and make more aromatic structure remain in the char. And CP@PA has a synergistic effect with APP to promote EP to form porous intumescent char layer with a higher graphitic degree, which protects the composites from the flame. As a result, the combination of CP@PA and APP in EP achieved a lower addition of flame retardant and better waterproof and fire safety performance, which provides a specific experimental and theoretical basis for the further application of CP@PA in epoxy resin. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride/polyaniline doped with phosphoric acid (g-C 3 N 4 /PANI@PA) hybrids was prepared by polymerising aniline monomer on the surface of g-C 3 N 4 nanosheets, which used an in-situ chemical oxidative polymerisation method. Intumescent fire retardant (IFR) epoxy coatings with g-C 3 N 4 /PANI@PA were prepared, and fire resistance and waterproofing performance of coatings were investigated. The energy dispersive X-ray spectrometry image showed phosphorus element dispersing evenly on the fracture surface of epoxy composite with 0.25 wt% g-C 3 N 4 /PANI@PA (EP-0.25CP@PA), which indicated that g-C 3 N 4 /PANI@PA dispersed in coating evenly. The results of the cone calorimeter test (CCT) showed that the values of peak heat release rate (pHRR), total smoke release (TSR), total carbon monoxide production (TCOP) of pure epoxy resin (EP-0) were 1389.0 kW/m2, 22.6 m2 and 3.6 g, respectively. In addition, the related data of intumescent fire retardant coating (EP-IFR) were 374.8 kW/m2, 12.9 m2, and 2.1 g, respectively. When 0.25 wt% g-C 3 N 4 /PANI@PA was introduced into EP-IFR to get EP-IFR-0.25CP@PA sample, the pHRR, TSR, and TCOP values were reduced to 347.3 kW/m2, 7.9 m2, 1.5 g, which were reduced by 75.0%, 65.0%, and 60.0% compared with EP-0, respectively. Furthermore, g-C 3 N 4 /PANI@PA could also improve the hydrophobicity of IFR epoxy coatings. The water contact angle increased from 50.0° (EP-IFR) to 84.8° (EP-IFR-0.25CP@PA). It was confirmed that g-C 3 N 4 /PANI@PA could improve the fire protection, smoke suppression performance, and waterproof performance of IFR epoxy coating. All of those provide a certain theoretical support for applying g-C 3 N 4 /PANI@PA in intumescent fire retardant coatings. • G-C 3 N 4 /PANI@PA were prepared as flame retardant for IFR epoxy coating. • g-C 3 N 4 /PANI@PA can improve the fire protection, smoke and toxic gas suppression performance of IFR epoxy coating. • g-C 3 N 4 /PANI@PA can promote the cross-linking and carbonization of IFR epoxy coating. [ABSTRACT FROM AUTHOR]