MOLECULES
·
2022
·Vol. 27
·期 15
·4748
·
IF 4.927
Qing Zhang,Huiyuan Liu,Junxia Guan,Xiaochun Yang,Baojing Luo
Phosphating sesbania gum (DESG) was obtained by modifying sesbania gum (SG) with 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and endic anhydride (EA). The structure of DESG was determined using Fourier transform infrared (FTIR) spectroscopy and nuclear magnetic resonance spectroscopy (1H-NMR). Flame-retardant polylactic acid (PLA) composites were prepared by melt-blending PLA with DESG, which acted as a carbon source, and ammonium polyphosphate (APP), which acted as an acid source and a gas source. The flame retardancy of the PLA composite was investigated using vertical combustion (UL-94), the limiting oxygen index (LOI) and the cone calorimeter (CONE) test. Thermal properties and morphology were characterized via thermogravimetric analysis (TGA) and field emission scanning electron microscopy (FESEM), respectively. Experimental results indicated that when the mass ratio of DESG/APP was equal to 12/8 the LOI value was 32.2%; a vertical burning test (UL-94) V-0 rating was achieved. Meanwhile, the sample showed a lowest total heat release (THR) value of 52.7 MJ/m2, which is a 32.5% reduction compared to that of neat PLA. Using FESEM, the uniform distribution of DESG and APP in the PLA matrix was observed. The synergistic effect of DESG and APP effectively enhanced the flame retardancy of PLA. Additionally, the synergistic mechanism of DESG and APP in PLA was proposed.Keywords:polylactic acid;sesbania gum;ammonium polyphosphate;flame retardancy
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MINERALS ENGINEERING
·
2020
·
IF 3.795
Peilun Shen,Dianwen Liu,Xiaohui Xu,Xiaodong Jia,Xiaolin Zhang,Kaiwei Song,Jinpeng Cai
In this study, for the first time, we applied ammonium phosphate to pre-treat chrysocolla prior to sulfidization flotation. In addition, we investigated the structural characteristics of the copper sulfide film formed on the chrysocolla surfaces and its response to flotation. Micro-flotation experiments revealed that the addition of (NH 4 ) 3 PO 4 prior to sulfidization greatly improves the floatability of chrysocolla and its recovery increased from 8.71% to 87.97% with butyl xanthate as the collector. The results of the field emission scanning electron microscopy analysis showed that numerous regular fragments appeared on the chrysocolla surfaces after the addition of (NH 4 ) 3 PO 4 . The X-ray diffraction and X-ray photoelectron spectrometry analysis confirmed that these fragments were newly formed copper sulfide covering the chrysocolla surfaces, during this process a chemical reaction occurred in the slurry system, i.e. the Cu 2+ were reduced to Cu + , the S 2− were mainly oxidized to S − , (S 2 ) − , (S 2 ) 2− . The copper sulfide species primarily in the form of crystalline covellite (Cu + 3 (S 2 ) 2− S − ), which is the key to obtaining good flotation recovery. As a specific activator, (NH 4 ) 3 PO 4 participates in the liquid-solid phase chemical reaction between the sulfidizing reagent and the chrysocolla, which promotes the sulfidization reaction of chrysocolla.
研究领域:
矿物加工工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2018
·
IF 5.158
Fengxiu Zhang,Weiwei Gao,Yaling Jia,Yi Lu,Guangxian Zhang
A new halogen-free and formaldehyde-free ammonium salt of melamine hexa(methylphosphonic acid) (AMHMPA) was facilely synthesized as flame retardant (FR) material under water-solvent and low temperature condition to counter inflammable cotton fabric fire hazard. The reactive P O(NH 4 ) 2 and PO(OH) 2 groups from AMHMPA reacted with cotton reactive OH groups to form P O C bonds. A layer of AMHMPA was coated onto the treated-cotton surface, and a carbon skeleton was formed after combustion. The char residue percentages of the treated-cotton fabrics and untreated fabric were 38.5 and 3.6% at 600 °C, respectively. The phosphorus contents for the control, treated-cotton and burned-cotton were 0, 37.499 and 24.896%, respectively. The LOIs of cotton treated with 30–90 g/L AMHMPA reached 32.0–43.0%. After 50 laundering cycles (LCs), the LOIs still maintained 26.0–33.4%. AMHMPA-treated cotton had no cytotoxicity towards the environment and humans. These results demonstrated that AMHMPA-treated cotton exhibited eco-friendly, outstanding durability and excellent flame retardancy. TG-IR and cone calorimeter results confirmed AMHMPA condensation phase flame retardant mechanism.
研究领域:
材料科学
·
纺织工程
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2020
·
IF 9.038
Wen-Xiong Li,Hai-Jun Zhang,Xiao-Ping Hu,Wen-Xue Yang,Zhou Cheng,Chang-Qiong Xie
The intumescent flame retardant (IFR) with ammonium polyphosphate (APP) as the main component has many defects in practical applications, more than that, APP can be traced to non-renewable phosphate rock resources. For the foregoing reasons, the melamine phytate supramolecular nanosheet flame retardant incorporating manganese ion (PAMA-Mn) was successfully prepared with a facile and environmental friendly hydrothermal procedure based on renewable bio-based material phytic acid (PA). The flame retardant polypropylene composite (PPI) with 13.5 wt% APP and 4.5 wt% pentaerythritol (PER) failed to the UL-94 test, and its limiting oxygen index (LOI) value was only 26.5%. After 33 wt% of APP was replaced by PAMA-Mn, the PPMn33 incorporating only 18 wt% flame retardant additives passed the UL-94 V-0 rating, and its LOI value was increased to 31.9%. Compared with PP, pHRR and pSPR values of PPMn33 were reduced by 56% and 23%, respectively. The fire retardant mechanism of PPMn33 was thoroughly discussed via a variety of characterization methods. It was found that the peak of the Gram-Schmidt curve of PPMn33 was drastically reduced by 49% relative to that of PPI, indicating a remarkably decrease of combustible volatile products owing to the incorporation of PAMA-Mn, thereby rapidly reducing the fire hazard risk.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2025
·
IF 8
Jinpeng Wang,Yang Su,Xue Yang,Fengrong Xin,Jian Wang,Chaoyi Fan,Zhen Yang,Dandan Peng,Zhehong Shen,Qun Fang,Sai Wu
As a bio-based wood product, plywood is widely used in furniture, flooring, packaging, architectural decoration, etc. However, the flammability of plywood limits its application. Using flame-retardant adhesives to prepare plywood is the simplest way to improve its flame-retardant properties. However, a challenge in flame-retardant adhesives arose from the negative effect of flame retardants on the curing and bonding properties of adhesives. Herein, we developed a method to prepare a flame-retardant adhesive modified by using Z-3A molecular sieves as carriers to load flame retardants such as phytic acid and ammonium polyphosphate. The flame-retardant performance of obtained plywood bonded by this flame-retardant adhesive was significantly improved with robust bonding strength under extraordinarily low loading of flame retardants. Even if the loading rate of ZPA flame retardant for 2-ZPA-5 plywood was as low as 2.2 %, the total smoke production and the maximal peak value of the heat release rate were reduced by 79 % and 14 %, respectively, with the limiting oxygen index being 33.6 %, the time to ignition delaying by 14 s, robust wet bonding strength being 1.79 MPa, anti-loss rate as 1.06 ± 0.18 %, and moisture absorption rate as 4.45 ± 0.14 %. The whole process needs neither tedious work or equipment nor high loading of flame retardants. This judicious design strategy offers a versatile and scalable approach to preparing flame retardant plywood.
研究领域:
材料科学
·
林业工程
✓ 已验证
产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2024
·
IF 8.2
Chao Wang,Ting Jiang,Junwei Huang,Min Chen,Huimin Hu,Lei Peng,Lei Wu,Zeng Chaocheng,Qiwu Zhang
The remediation of high-concentration thallium (Tl + ) contaminated wastewater is a critical environmental concern. Current research emphasizes the effectiveness of adsorption and oxidation methods for Tl + treatment, yet challenges persist in enhancing their performance. This study explores the feasibility of emergency Tl + wastewater treatment and elucidates the mechanisms of Tl + incorporation into mineral structures, with a focus on the struvite mineral as a framework for Tl + integration via NH 4 + ion exchange. To assess the efficacy and mechanisms of Tl + immobilization, we utilized comprehensive analytical techniques, including X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), Fourier-Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy with Energy-Dispersive X-ray Spectroscopy (SEM-EDS), Thermogravimetric Analysis (TG), and Density Functional Theory (DFT) calculations. The findings reveal that struvite adsorbs Tl + onto its surface, followed by an ion exchange process between monovalent cations (NH 4 + /K + ) within the structure and Tl + . Ultimately, Tl + is incorporated in the form of a (NH 4 ,Tl)MgPO 4 solid solution within the structure, achieving a remarkable maximum incorporation capacity of 320.56 mg/g, which significantly surpasses the capacity of typical adsorbents. The findings demonstrate significant Tl + incorporation, validating the approach for emergency wastewater treatment and suggesting the potential of mineralogy in environmental remediation. This research contributes to advancing heavy metal wastewater treatment strategies, offering a foundation for further investigation.
研究领域:
环境科学
·
矿物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2024
·
IF 6.3
Xuqiang Zheng,Xinyu Chen,Xiaorong Guo,Jun Sun,Hongfei Li,Xiaoyu Gu,Sheng Zhang
Polypropylene (PP) has the advantages of excellent mechanical properties and easy molding, but its shortcomings such as high flammability and poor ultraviolet (UV) resistance cannot be ignored. In this paper, APP was used as the core, 1, 10-diamino-decane (DA) was used as a "bridge" to connect TA to the surface of APP, obtaining TAPP through oxidation self-polymerization. The addition of TAPP greatly improved the flame retardancy and UV resistance of PP matrix. The limiting oxygen index of the PP/22.5 %TAPP sample was increased to 31.0 %, and it was able to pass the UL-94 V-0 rating without droplet produced. Compared with PP samples, the peak heat release rate and peak smoke release rate of PP/22.5 %TAPP sample were reduced by 65.0 % and 44.7 %, respectively. In addition, the tensile strength and impact strength of PP/22.5 %TAPP samples decreased by only 2.7 % and 15.0 % after 60 h UV irradiation. The results showed that the addition of TAPP effectively improved the flame retardancy and UV aging resistance of PP. This study provides a feasible method for the preparation of anti-UV aging and flame-retardant PP composites.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Yanming Wang,Ruijie Guo,Jie Zhang,Huifang Wang,Baolong Niu,Hong Yan
In general, the addition of flame retardants may lead to the degradation of the mechanical properties of polymers, despite enhancing their flame retardancy. However, flame-retardant coatings have the potential to provide good flame resistance to polymers without compromising their inherent mechanical properties. In this study, we applied highly adhesive and flexible polysiloxane flame-retardant coatings (196 μm) to polypropylene , resulting in reductions of 74.9 %, 58.0 %, 80.0 %, and 56.4 % in peak heat release rate , peak smoke production rate, fire growth rate, and mass loss, respectively. By incorporating the lab-synthesized DOPO-modified polysiloxane (APID), the flame-retardant efficiency of ammonium polyphosphate (APP) was greatly enhanced. The primary film-forming agent, (3-aminopropyl) triethoxysilane (APTES), played a key role in maintaining the compatibility of APP and APID with the coating, as well as facilitating the formation of a robust Si O Si crosslinked network structure that strengthened the resulting char layer. The interactivity between the various components, including hydrogen bonds and crosslinked network structures, contributed to improved uniformity, thermal stability, and adhesion of the coatings. Moreover, the coatings exhibited resistance to ultraviolet radiation and water. Our findings suggest that highly flexible and adhesive flame-retardant coatings hold significant potential for applications in polymer protection. These promising results provide a viable pathway for improving the fire protection of polymers through the use of high-adhesive intumescent flame-retardant coatings.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Can Liu,Xinru Li,Qiming Duan,Xiaoping Yu,Yafei Guo,Tianlong Deng
There are abundant strontium resources in oilfield water with vast economic potential, but they have not yet been explored due to the complex matrix composition and the lack of cost-effective extraction technologies. Herein, four kinds of α -type ammoniated phosphates (A-MPs, M(NH 4 PO 4 ) x (HPO 4 ) 2- x ; M = Zr, W, Mo, and Ti, 0 ≤ x ≤ 2) were designed and compared based on Density Functional Theory (DFT) calculations. It was inferred that ammoniated titanium phosphate (A-TiP) has both high structural stability and superior Sr 2+ adsorption performance due to its low formation energy and Sr 2+ adsorption energy. This conclusion was confirmed by the synthesis of A-TiP through a simple solid-state synthesis, and the maximum adsorption capacity of the optimized A-TiP was 320.9 mg·g −1 . To facilitate the industrial application of powdery A-TiP, it was further fabricated into fibers by wet spinning technology with low-cost PVC as the binder. Since the mesoporous structure and high stability of the obtained adsorbent (PVC-A-TiP), it still exhibited a high maximum adsorption capacity ( q max = 291.75 mg·g −1 ), strong adaptability (active pH = 4 ∼ 12), and a short adsorption equilibrium time ( t e = 60 min). When applied for Sr 2+ recovery from complex oilfield water, the distribution coefficient of Sr 2+ reached 11740.21 mL·g −1 , and the dynamic adsorption capacities ranged from 121.61 to 162.46 mg·g −1 . The material also showed excellent cycle stability, and the adsorption performance did not decrease even after 50 adsorption-desorption cycles. These excellent results demonstrate that the developed material can be employed as a potential adsorbent for selective extraction of Sr 2+ from oilfield water or other liquid Sr minerals.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2025
·
IF 8
Chao Yan,Yiqun Fang,Mengfan Yan,Ruofan Yang,Weihong Wang,Yongming Song,Qingwen Wang
Ammonium polyphosphate (APP) and hydrophobic multiwalled carbon nanotubes (M-MWCNT) were introduced into wood to impart flame-retardant properties and hydrophobic. First, the wood was partial delignification followed by TEMPO oxidation (denoted DW). APP and M-MWCNT were then sequentially vacuum impregnated to obtain the DW@APP@M-MWCNT composite. The resulting DW@APP@M-MWCNT exhibited a limiting oxygen index (LOI) of 39.5 %, passed the UL-94–0 vertical combustion test, and showed a 39.86 % reduction in total heat release (THR) in the MCC test compared to DW. Additionally, the graphitization degree (ID/IG) of DW@APP@M-MWCNT was 31.82 % lower than that of DW@APP. After combustion, the wood retained its original structure. The FT-IR, TG-IR, and XPS analyses reveal that the flame-retardant mechanism of APP and M-MWCNT in DW is primarily a combined effect of radical trapping, synergistic charring, and thermal inhibition. This study provides an effective method for fabricating wood with both flame-retardant and hydrophobic properties.
研究领域:
材料科学
·
林业工程
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2015
·
IF 2.587
Jian-Chao Liu,Miao-Jun Xu,Tao Lai,Bin Li
Ammonium polyphosphate (APP), which is an important component of intumescent flame retardant (IFR), has been modified with (3-aminopropyl) triethoxysilane (KH550) and silicon resin to enhance its hydrophobic properties. The structure and properties of the modified ammonium polyphosphate (MAPP) were well-characterized by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy (SEM), and water contact angle (CA). The water CA of MAPP was as high as 148°, which demonstrated that MAPP possessed excellent hydrophobic properties. MAPP and APP were mixed with triazine, which is a char-foaming agent (CFA), and polypropylene (PP) to prepare PP/MAPP/CFA and PP/APP/CFA composites, respectively. The fire retardancy and thermal degradation behavior of PP/MAPP/CFA and PP/APP/CFA composites were investigated by limiting oxygen index (LOI), vertical burning test (UL-94), cone calorimetry, and thermogravimetric analysis. The surface and fracture morphologies were evaluated by SEM. The mechanical properties was analyzed by tensile, flexural, and izod impact tests. The results demonstrated that the MAPP imparted excellent flame retardancy of PP/MAPP/CFA systems, along with a higher LOI value, UL-94 rating, and lower heat release rate and total heat released values. The modification enhanced the interfacial adhesion, mechanical stability, and thermal stability of PP/MAPP/CFA composites. Moreover, PP/MAPP/CFA composites with the thickness of 1.6 mm can still pass the UL-94 V-0 rating after treatment with water for 168 h at 70 °C, meanwhile the weight loss rate was decreased from 2.31% for PP/APP/CFA composites to 0.85%, indicating excellent water resistance. This investigation shows a promising formulation for water-resistant intumescent flame-retardant PP composites with extraordinary properties.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Peiwen Xue,Yajie Cheng,Yong Wang,Gaojie Han,Bing Zhou,Chengen He,Chuntai Liu,Yuezhan Feng
Three-dimensional (3D) boron nitride skeleton has a promising prospect in improving the thermal conductivity and flame retardancy of polymer composites, yet the problems of interface thermal resistance and combustion collapse in the skeleton caused by organic adhesives still need to be solved. In this work, macromolecular flame retardancy, ammonium polyphosphate (APP) with high polymerization degree, was firstly used to modify and assemble boron nitride nanosheets (BNNS) into 3D thermally conductive skeleton, in which APP with rich amino groups can result in the strong grafting modification to reduce the interfacial thermal resistance in BNNS skeleton, meanwhile, the catalytic carbonization of APP can reinforce the 3D skeleton barrier without collapse during combustion. Typically, one-step wet ball-milling with assisted APP was used to exfoliate and modify BNNS, followed by unidirectional freezing to achieve 3D BNNS@APP skeleton with highly oriented structure. As expected, the constructing 3D skeleton with low interfacial thermal resistance can effectively form a heat transfer path in polymer matrix. The obtained epoxy-based composite showed a high thermal conductivity of 3.28 W/mK at 9.28 vol% BNNS@APP. Meanwhile, the producing 3D skeleton barrier during combustion induced the significant improvement in flame retardancy, with heat release rate (HRR) and total heat release (THR) decreasing by 68.3% and 52.7%, respectively. This work provides a new adhesive choice in constructing 3D thermal conductive and flame retardant skeleton, which exhibits high potential in thermal management application.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）