- Synthesis and characterization of SPDSCD and its flame retardant application on epoxy resins
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In this study, a flame retardant agent, 2,4,8,10-tetraoxo-3,9-diphosphospiro[5.5]undecane spirophosphate-4,4-diaminopair benzene disulfone-1,3,5-himetriazine (SPDSCD), is synthesized through a direct polycondensation reaction. SPDSCD is a chemically expanded phosphorus-containing flame retardant in epoxy resins (EP). The molecular structure of SPDSCD and thermal stability are characterized by nuclear magnetic resonance, Fourier transform infrared spectroscopy, and thermogravimetric analysis, and EP/SPDSCD composites were investigated in detail. These properties are associated with the phosphorus-containing spiro structure on the main molecular chain which can promote condensation polymerization into carbon during pyrolysis, the new nitrogen-containing carbon source, and the triazine structure. SPDSCD shows good thermal stability and low flammability, the weight loss from 500 to 800 °C was only 6.1 wt%, and the residual mass at 800 °C was 48.9 wt%. With the addition of SPDSCD, the flame retardant quality of the composites was gradually enhanced, the carbon residue becomes denser, which isolates heat transfer and inhibits the volatilization of flue gas. The addition of 20 wt% SPDSCD in the EP sample was associated with a limited oxygen index (LOI) value of 26% and a vertical burning V-0 rating. Cone calorimeter test shows that the peak heat release rate is reduced by 75%; the heat release rate curve enters the heat release platform area with a value lower than the first peak, TSP is reduced by 24%, the ac-CO2Y value reduced by 25.6%, indicating that SPDSCD/EP produced less CO2, which obviously prevented the combustion of volatile gas. SPDSCD exerted a charring and barrier effect in the condensation phase. Using basic characterization and flame retardancy testing, this work determined that SPDSCD has good flame retardancy when added to EP.
- Li, Shulei,Liu, Jiping,Ruan, Fang,Yang, Weiwei,Zhang, Yi,Zhao, Wei
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- Functionalized graphene oxide/phosphoramide oligomer hybrids flame retardant prepared via in situ polymerization for improving the fire safety of polypropylene
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A novel strategy based on functionalized graphene oxide (FGO)/phosphoramide oligomer flame retardant was developed to overcome the challenges of the dispersion of graphene sheets in polymer matrix and the ease of the burn-out of graphene under air atmosphere. Graphene oxide (GO) was modified by 4,4-diaminodiphenyl methane (DDM) and then in situ incorporated into phosphoramide oligomer, resulting in a nanocomposite flame retardant (FRs-FGO) containing exfoliated graphene. Subsequently, the flame retardant (FRs-FGO) was incorporated into polypropylene (PP) and simultaneously compatilized with PP-grafted maleic anhydride. TEM results showed that the FGO was dispersed more uniformly in PP than the bare GO because of the strong interfacial interaction and previous exfoliation of FGO in FRs before blending. The thermal properties investigated by thermogravimetric analysis (TGA) indicated that the addition of FRs-FGO into PP resulted in a significant improvement of thermal stability at elevated temperature with higher char yields. Moreover, the crystallization and fire safety properties of PP composites were also improved by the incorporation of FRs-FGO, including increased crystallization temperature (11.4 °C increase), reduced peak heat release rate (66.9% reduction) and decreased total heat release (24.4% decrease), and decreased fire growth rate index (73.0% decrease). The cone results indicated the simple blending of GO with FRs and exhibited less improvement in fire safety properties than FRs-FGO, which resulted from the improved dispersion and thermal stability of FGO sheets. The flame retardant mechanism was because of the shielding effect of FGO and char layers, which could reduce the release of combustible gases and inhibit the mass and heat transfer between the gas phase and condensed phase.
- Yu, Bin,Wang, Xin,Qian, Xiaodong,Xing, Weiyi,Yang, Hongyu,Ma, Liyan,Lin, Ying,Jiang, Saihua,Song, Lei,Hu, Yuan,Lo, Siuming
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- Preparation, fire behavior and thermal stability of a novel flame retardant polypropylene system
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In this study, a novel spirocyclic pentaerythritol bisphosphorate disphosphoryl-di-prop-2-en-1-amine (SPSA) compound containing a functional double bond (C=C) was synthesized and characterized by Fourier transform infrared spectroscopy and 1H nuclear magnetic resonance spectroscopy (1H NMR). In this paper, a new intumescent flame retardant (IFR) was designed by combining ammonium polyphosphate (APP) and SPSA (mass ratio of APP and SPSA was 2:1) and this IFR was mixed with polypropylene (PP) via twin-screw extruder to prepare a series of flame retardant PP composites. The thermal stability and fire behaviors of these flame retardant PP composites were investigated by thermogravimetric analysis, limiting oxygen index (LOI), vertical burning test (UL-94) and cone calorimeter test. Furthermore, the morphology of the char residues of flame retardant PP composites after cone calorimeter test was studied by scanning electron microscopy with energy dispersive X-ray analysis (EDS). Aiming to further improve the thermal stability of the composites, electron beam irradiation has been used to treat these composites. The results showed that LOI value of flame retardant PP composite containing 30?% IFR was 24.0 and passed UL 94?V-0. In the cone calorimeter test, both peak heat release rate and total heat release results of PP/IFR system were lower than those of PP/APP system. In addition, this IFR provided relatively good quality of char residue in the combustion. Moreover, electron beam treatment of the composites improved the thermal stability of these designed flame retardant PP composites.
- Xiao, Dan,Li, Zhi,De Juan, Sergio,Gohs, Uwe,Wagenknecht, Udo,Voit, Brigitte,Wang, De-Yi
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- Flame retardancy and thermal degradation mechanism of epoxy resin composites based on a DOPO substituted organophosphorus oligomer
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A series of flame-retardant epoxy resins (EP) with different content of poly(DOPO substituted dihydroxyl phenyl pentaerythritol diphosphonate) (PFR) were prepared. The PFR was synthesized via the polycondensation between 10-(2,5-dihydroxyl phenyl)-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO-BQ) and pentaerythritol diphosphonate dichloride (SPDPC). The structure of PFR was confirmed by Fourier transform infrared spectroscopy (FTIR) and 1H nuclear magnetic resonance (1H NMR). The flame retardancy and the thermal stability of the EP/PFR hybrids were investigated by limiting oxygen index (LOI) test and thermogravimetric analysis (TGA) in air. The results showed that the incorporation of PFR into EP can improve the thermal stability dramatically. The mechanical results demonstrated that PFR enhanced failure strain slightly accompanied by a decrease in tensile strength. The thermal oxidative degradation mechanisms of the EP/PFR hybrids were investigated by real time Fourier transform infrared spectra (RTFTIR) and direct pyrolysis/mass (DP-MS) analysis. X-ray photoelectron spectroscopy (XPS) was used to explore chemical components of the residual char of EP and EP/PFR hybrid. DP-MS analysis showed that the degradation process of EP/PFR hybrid was divided into two characteristic temperature regions, attributed to the decomposition of phosphate and aromatic structure.
- Wang, Xin,Hu, Yuan,Song, Lei,Xing, Weiyi,Lu, Hongdian,Lv, Pin,Jie, Ganxin
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- Novel phosphorus-containing silazanes as flame retardants in epoxy resins
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Molecules containing different elements and moieties like P-N and P-O-Si have high impact on flame retardant properties. In this study, a novel group of flame retardants based on phosphasilazanes containing a P-N-Si structure is established. Due to introduction of the silazane moiety to various phosphorus environments, further properties, like mechanical or thermal, besides flame retardancy can be altered. The influence of phosphorus or silicon moieties and their mode of action on flame retardant properties is examined. In formulations with a high-performance epoxy resin, thermal properties (glass transition temperature and moisture absorption) and flame retardant performance (UL94 vertical burning test, cone calorimetry) are investigated. Alteration of chemical environment at the phosphorus atom determines various implications on burning behavior. For example, phosphorus-containing moieties promoting char generation and intumescence enhance char yields and other parameters describing flame retardant properties of phosphasilazanes in thermo-analysis as well as in cone calorimetry. On the other hand, higher concentration of silazane groups in the structure leads to higher flammability. Phosphorus moieties acting in gaseous phase cause poor flame retardant properties because they antagonize the char generation of silazanes.
- D?ring, Manfred,Eibl, Sebastian,Greiner, Lara,Kukla, Philipp,Sch?nberger, Frank
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- Phosphate cross-linking agent and preparation method thereof, phosphate-based cross-linked gel polymer electrolyte and preparation method and application thereof
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According to the invention, the safety of the battery can be improved based on introduction of phosphate into the gel polymer electrolyte, , the adjustable flexibility is improved by introduction of aPEO chain segment, and the stability and the polymerization capability are improved by introduction of acrylate; thus, further research is carried out on the basis of the prior art, the polyfunctional phosphate cross-linking agent is obtained and is applied to the preparation of the phosphate-based cross-linked gel polymer electrolyte, so the cross linking agent can be copolymerized with other functional monomers to synthesize gel polymer electrolyte; the gel polymer electrolyte has the advantages of simple and convenient preparation method, high ionic conductivity, high thermal stability andgood electrochemical stability, the assembled sodium ion battery has good cycling stability and high-temperature performance, and the phosphate-based gel polymer electrolyte with high safety is provided for quasi-solid sodium/lithium ion batteries.
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Paragraph 0047-0048; 0051
(2020/08/17)
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- Pentaerythritol pair of phosphoric acid ester ethylamine and its preparation method and application
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The present invention provides pentaerythritol pair of phosphoric acid ester ethanolamine, chemical structure shown in formula I, can be used as halogen-free flame retardant to be applied to the expansion. The results show that the embodiment, the cationic pentaerythritol pair of phosphoric acid ester ethanolamine to the Dacron, polyamide, cotton, blended cloth and disinfecting has excellent flame retardant effect, can achieve UL - 94 B1 and B2 and V0 level. The invention also provides the cationic pentaerythritol pair of phosphoric acid ester of ethanolamine preparation method, the pentaerythritol, phosphorus oxychloride, catalyst and organic solvent after the reaction of acyl, get the pentaerythritol pair of phosphoric acid ester b phosphorus chloride; to the cationic pentaerythritol pair of phosphoric acid ester b phosphorus chloride hydrolysis, to obtain pentaerythritol bisphosphate; will the cationic pentaerythritol double-phosphoric acid and ethanolamine amination reaction, to obtain pentaerythritol pair of phosphoric acid ester ethanolamine. The preparation of the method is the raw material is low, the operation process is simple, easy to implement.
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Paragraph 0064-0069
(2018/07/30)
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- A water-based polyurethane reactive intumescent fire retardant and its preparation method
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The invention relates to the field of fine chemical engineering materials and specifically relates to a reactive type intumescent flame retardant for water-based polyurethane, which simultaneously contains a carbon source, an acid source, a gas source and active amino groups, and a preparation method of the reactive type intumescent flame retardant. The chemical structure of the reactive type intumescent flame retardant disclosed by the invention is as shown in formula I, the obtained flame retardant does not contain halogen, has relatively high content of phosphorus and nitrogen flame retardant components and shows an aromatic heterocyclic structure, thereby having good stability at high temperature, high char yield, significant intumescence and excellent flame retardance. Two active primary amino hydrogen ions contained in the structure can react with isocyanate to prepare flame-retardant water-based polyurethane, thereby not only effectively solving the problems of poor compatibility, easiness in migration, precipitation and permeation and the like of a traditional complex additive type flame retardant in a water-based polyurethane system, but also overcoming the defect that the physical and mechanical properties of water-based polyurethane become poor caused by the complex additive type flame retardant. When the reactive type intumescent flame retardant provided by the invention is used for preparing water-based polyurethane, the process is easy to control, the properties are easy to regulate, and prepared water-based polyurethane is widely applied to leather finishing, synthetic leather coatings, fabric coatings, building fireproof materials, coating materials, adhesives and other industries. The formula I is described in the specification.
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Paragraph 0042; 0045; 0047-0048; 0051
(2017/08/25)
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- Synthesis method of novel reactive bicyclophosphate flame retardant
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The invention provides a synthesis method of a novel reactive bicyclophosphate flame retardant. The optimal technological conditions for synthesizing the intermediate pentaerythritol bisphosphorate diphosphoryl chloride (PDD) from phosphorus oxychloride and pentaerythritol are as follows: a certain amount of dichloromethane is used as a solvent, a certain amount of triethylamine is used as an acid-binding agent, the mole ratio of the reactants pentaerythritol and phosphorus oxychloride is 1:2.1, the reaction temperature is 50 DEG C, and the reaction time is 6 hours. The optimal technological conditions for synthesizing the target product pentaerythritol bisphosphorate diphosphoryl chloride propenol salt (PDA) are as follows: the mole ratio of the reactants PDD and propenol is 1:2.2, and the reaction is carried out for 8 hours under ice bath conditions. The method has the advantage of simple technique, and is green and environment-friendly. The novel flame retardant synthesized by the method has the advantages of no halogen, no toxicity, high heat stability and the like, can well overcome the defects of low flame-retardant efficiency, high migration tendency, poor compatibility with high-molecular materials and the like in the additive-type phosphorus flame retardant, conforms to the environmental requirements which are advocated at present, and has wide development prospects.
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Paragraph 0019-0021
(2017/09/02)
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- Preparation and properties of main chain phosphorus containing poly(trimethylene terephthalate) block copolymers
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A series of phosphorus-containing poly(trimethylene terephthalate) multiblock copolymers were synthesized and characterized on their chemical structure, average molecular weight, thermal stability and flame retardancy. The dihydroxypropyl pentaerythritol phosphate was prepared by using 1,3-propanediol and dichloro phosphorspirol. The phosphorus-containing copolymers were prepared by transesterification and melt-polycondensation method. The results suggest that the block copolyesters were successfully prepared and it shows the characteristics of the intumescent flame retardancy. With increasing phosphorus content in main-chains, the block copolyesters show reduced initial degradation temperatures but increased char residue and gradually increased limiting oxygen index. The dichloro phosphorspirol component contributes flame retardancy in the copolyesters.
- Cai, Xueming,Lv, Shufang,Jia, Panjin,Han, Qing,Run, Mingtao
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p. 2559 - 2563
(2015/12/12)
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- DINUCLEOTIDE COMPOUNDS FOR HCV INFECTION
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Provided herein are compounds, compositions and methods for the treatment of Flaviviridae infections, including HCV infections. In certain embodiments, compounds and compositions of nucleoside derivatives are disclosed, which can be administered either alone or in combination with other anti-viral agents. In certain embodiments, the compounds comprise two 2′-methyl nucleotides linked according to Formula I: [in-line-formulae]N1-L-N2??(I)[/in-line-formulae] or a pharmaceutically acceptable salt, ester, solvate, stereoisomer, isomeric form, tautomeric form or polymorphic form thereof; wherein N1, L and N2 are as described herein.
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Paragraph 0388; 0389; 0390
(2014/05/07)
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- Synthesis and thermal properties of spiro phosphorus compounds
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Intumescent materials, 3,9-dichloro-2,4,8,10-tetraoxa-3,9-diphosphaspiro- [5,5]-undecane-3,9-dioxide and 3,9-dichloro-2,4,8,10-tetraoxa-3,9- diphosphaspiro-[5,5]-undecane having the capacity to produce dehydrating agent, blowing agent, and undergo carbonization during burning have been synthesized. The thermal behavior of the synthesized materials was investigated using differential thermal analysis, thermal volatilization analysis, programmed vacuum pyrolysis-mass spectrometry, flash pyrolysis-mass spectrometry and off-line pyrolysis-gas chromatography-mass spectrometry. The materials show exothermic degradation after 250 °C. Monitoring the release of hydrogen chloride and water, the blowing agents for the production of carbon foam, clearly indicated the superior performance of the pentavalent phosphorus compound over the trivalent phosphorus compound. The major gaseous degradation products released during pyrolysis showed the presence of sufficient quantities of several alkyl-substituted benzenes and fused aromatics. Suitable degradation mechanism has been proposed and discussed to explain the formation of various organics during thermal degradation.
- Vijayakumar, Chinnaswamy Thangavel,Mathan, Nagarajan David,Sarasvathy, Vijayakumar,Rajkumar, Thangamani,Thamaraichelvan, Arunachalam,Ponraju, Durairaj
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experimental part
p. 281 - 287
(2010/09/17)
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- Hydrogen phosphonates
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The present invention relates to cyclic phosphorus compounds and processes for the preparation thereof. The present invention relates to a process for the preparation of certain derivatives of cyclic hydrogenphosphonates which are diisocyanate derivatives formed as adducts or as polymers. The cyclic phosphorus compounds are useful as flame retardants with organic polymers, such as polyurethanes, polyesters, and polyamides.
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