scholarly journals Application of modified phytic acid as flame retardant in cellulosic paper

BioResources ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. 7953-7965
Author(s):  
Qijie Chen ◽  
Zhi Rong ◽  
Zhuo Liu ◽  
Na You ◽  
Guangyang Xie
Keyword(s):  
Flame Retardant ◽  
Phytic Acid ◽  
Oxygen Index ◽  
Impregnation Method ◽  
X Ray Diffraction ◽  
Limiting Oxygen Index ◽  
X Ray ◽  
Char Length ◽  
Cellulosic Paper ◽  
Scanning Electron

A flame retardant containing phosphorus and nitrogen was synthesized using phytic acid and dicyandiamide, and it was subsequently used to prepare flame-retardant cellulosic paper via an impregnation method. Vertical flame and limiting oxygen index (LOI) were used to evaluate the flame retardancy of the paper. The paper containing modified phytic acid was characterized with Fourier transform infrared spectroscopy (FTIR), thermogravimetry (TG), X-ray diffraction (XRD), and scanning electron microscopy (SEM). When the concentration of modified phytic acid was 20%, the char length of the treated paper decreased from 12.5 cm to 4.1 cm, the LOI value increased from 19.6% to 41.5%, and the tensile index was only 3.66% lower than that of the control paper. The modified phytic acid was judged to have good flame-retardant effects on the paper.

The intercalation of ammonium sulfamate into kaolinite and its effect on the fire performance of polypropylene

2017 ◽  
Vol 31 (10) ◽  
pp. 1352-1370 ◽  
Author(s):  
Wufei Tang ◽  
Hongfei Li ◽  
Sheng Zhang ◽  
Jun Sun ◽  
Xiaoyu Gu
Keyword(s):  
Flame Retardant ◽  
Oxygen Index ◽  
Potassium Acetate ◽  
Limit Oxygen Index ◽  
Fire Performance ◽  
X Ray Diffraction ◽  
X Ray ◽  
Peak Heat Release Rate ◽  
Ammonium Sulfamate ◽  
Xrd Patterns

Kaolinite has often been intercalated before being introduced into polymers to improve its dispersibility; however, the conventional intercalation usually reduces the flame retardancy of the composite. This work reports our recent efforts on improving both the flame retardant efficiency and dispersibility of kaolinite in polypropylene (PP) by intercalating with ammonium sulfamate (AS). The intercalation had been performed through three steps: dimethyl sulfoxide was firstly introduced into kaolinite layers under supersonic wave, then it was replaced by potassium acetate-aqueous (KAc), and finally the intercalated KAc was replaced by AS to obtain AS-intercalated kaolinite. The structure of intercalated kaolinite was characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy, and thermogravimetric analysis (TGA). The flammability evaluation by limit oxygen index, vertical burning test (UL-94), cone calorimeters test (CONE), and TGA indicated that the fire resistance, thermal stability, and physical properties of PP can be effectively enhanced by the introduction of AS-intercalated kaolinite. The peak heat release rate (pHRR) value of PP composite containing only 1.5 wt% intercalated kaolinite (1169 kW m−2) had been reduced 13.2% compared with that of the sample containing 1.5 wt% raw kaolinite (1346 kW m−2). The morphology analysis from scanning electron microscope images and XRD patterns demonstrated that the compatibility and dispersibility of kaolinite in PP had been significantly improved by intercalation. The flame retardant mechanism of AS-intercalated kaolinite in PP was proposed.

Platinum Reduction Study on Pt/C Electro-catalysts for PEMFC

2013 ◽  
Vol 16 (3) ◽  
pp. 141-145
Author(s):  
M.L. Hernandez-Pichardo ◽  
R. Gonzalez-Huerta ◽  
P. del Angel ◽  
E. Palacios-Gonzalez ◽  
M. Tufiño-Velazquez ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Uv Light ◽  
Reducing Agents ◽  
Impregnation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Synthesis Conditions ◽  
Platinum Species ◽  
Scanning Electron

Platinum reduction on Pt/C catalysts was studied on samples prepared by the impregnation method using different Pt precursors and reducing agents such as ethanol, sodium borohydride and ethanol-UV light (photo-assisted reduction), in order to compare the efficiency of the different reducing agents. The influence of the reduction level of the platinum species on the electrochemical behavior of these catalysts has been determined. The catalysts were characterized by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and linear and cyclic voltammetry. The results show that the reduction level depends mainly on the platinum precursor. Moreover, it was found that the higher electrochemical activity was found using catalysts reduced with ethanol, whereas by using NaBH4 as the reducing agent, the total reduction of the platinum precursor is very difficult in same synthesis conditions. The analysis of the XPS results shows that samples reduced with ethanol presented the lower PtOx/Pt reduction ratio.

Effect of Chitosan as Antimicrobial Agent on Flame Retardant Protein Viscose Fiber

2012 ◽  
Vol 427 ◽  
pp. 32-37 ◽  
Author(s):  
Zhou Zhao ◽  
Qing Shan Li ◽  
You Bo Di ◽  
Xin Wang ◽  
Wei Hong
Keyword(s):  
Flame Retardant ◽  
Oxygen Index ◽  
Protective Layer ◽  
Viscose Fiber ◽  
Cross Linking ◽  
Sem Images ◽  
Limiting Oxygen Index ◽  
Viscose Fibers ◽  
Scanning Electron ◽  
Made In

The effects of chitosan as the antimicrobial on Protein viscose fibers were studied in this research. Antimicrobial flame-retardant protein viscose fibers are more efficient compared with original flame-retardant protein viscose fiber in improving the limiting oxygen index (LOI) of fiber. The effectiveness of the microstructure was investigated using scanning electron microscope (SEM).SEM images showed that the antimicrobial finishing and the softener were made in a same bath, which might be due to the formation of a protective layer or cross linking effect.

Synthesis of Cotton Fibers Impregnated with Bactericidal Hydrotalcites to be used in Medical Textile Supplies

MRS Advances ◽  
2017 ◽  
Vol 2 (61) ◽  
pp. 3787-3795 ◽  
Author(s):  
Ana María León-Vallejo ◽  
Geolar Fetter ◽  
Álvaro Sampieri ◽  
Efraín Rubio-Rosas
Keyword(s):  
Cotton Fibers ◽  
Impregnation Method ◽  
X Ray Diffraction ◽  
Mechanical Mixing ◽  
Orbital System ◽  
X Ray ◽  
Ultrasonic Apparatus ◽  
Medical Textile ◽  
Double Hydroxides ◽  
Scanning Electron

ABSTRACTHydrotalcites or layered double hydroxides are solids having laminar structures with remarkable basic properties. They can be synthesized with bactericidal metal ions incorporated into the structure. Both, basic species and metals can provide a high activity against microorganisms. Regarding this, it should be interesting to obtain a novel composite material consisting of cotton fibers impregnated with antimicrobial hydrotalcites to be used, for example, in medical textile supplies. In the present study, the retention of antimicrobial hydrotalcites in cotton fibers using mechanical mixing procedures was evaluated. The impregnation was carried out by three procedures, consisting in stirring the hydrotalcite with the cotton fibers in a rotatory or orbital system or in an ultrasonic apparatus. Composites were characterized by X-ray diffraction, infrared spectroscopy, scanning electron microscopy and energy dispersive X-ray spectroscopy. The retention of hydrotalcites in the fibers depended on the impregnation method. The composite obtained by the ultrasound procedure showed better retention.

scholarly journals Effects of chemical pre-treatment on structure and property of polyacrylonitrile based pre-oxidized fibers

2020 ◽  
Vol 15 ◽  
pp. 155892501989894
Author(s):  
Xiaolu Sun ◽  
Jiayin Song ◽  
Jin Zhang ◽  
Jingyan Liu ◽  
Huizhen Ke ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Thermal Stability ◽  
Heat Release ◽  
Flame Retardant ◽  
Oxygen Index ◽  
Energy Dispersive Spectrometer ◽  
Chemical Compositions ◽  
Limiting Oxygen Index ◽  
X Ray ◽  
Pre Treatment

Polyacrylonitrile-based pre-oxidized fibers with improved thermal stability, flame retardant, and mechanical properties were made from the pristine polyacrylonitrile fibers through chemical pretreatment followed by pre-oxidation in air. The morphological structure of the polyacrylonitrile-based pre-oxidized fibers was investigated by Fourier transfer infrared spectra, X-ray diffraction, scanning electron microscopy, and X-ray energy dispersive spectrometer. The changes of characteristic functional groups and chemical compositions confirmed the successful modification of the polyacrylonitrile fibers during pre-treatment. The grooves and cracks on the surface of polyacrylonitrile-based pre-oxidized fibers were remarkably decreased in comparison with that of pristine polyacrylonitrile fibers. The evolution of crystalline structure of the polyacrylonitrile fibers proved the occurrence of cyclization reactions during pre-oxidation. Meanwhile, thermal stability, flame retardant, and mechanical properties of polyacrylonitrile-based pre-oxidized fibers were also investigated by thermogravimetric analyzer, oxygen index meter, micro combustion calorimeter, and single fiber tensile tester, respectively. The results demonstrated that the polyacrylonitrile-based pre-oxidized fibers initially pre-treated by hydroxylamine hydrochloride, followed by monoethanolamine, had a high limiting oxygen index of 40.1 and breaking strength of 2.03 cN/dtex. The peak of heat release rate and total heat release of polyacrylonitrile-based pre-oxidized fibers decreased significantly while its charred residues increased, contributing to the improved flame retardant property.

Preparation and Flammability Properties of Polyethylene/Organoclay Nanocomposites

2018 ◽  
Vol 20 ◽  
pp. 92-105 ◽  
Author(s):  
Sara Verusca de Oliveira ◽  
E.A. dos Santos Filho ◽  
Edcleide Maria Araújo ◽  
C.M. Correia Pereira ◽  
Fábio Roberto Passador
Keyword(s):  
Maleic Anhydride ◽  
Flame Retardant ◽  
Flame Retardancy ◽  
Oxygen Index ◽  
Clay Content ◽  
X Ray Diffraction ◽  
Cone Calorimetry ◽  
X Ray ◽  
Mmt Clay ◽  
Ommt Clay

Polyethylene (PE) nanocomposites were prepared by melt intercalation, in order to evaluate the flame retardant effect of this material. For the development of nanocomposites were used the montmorillonite clay (MMT), organoclay (OMMT) and flame retardant product (FRP) with the percentage of 1, 3, 6 and 9 wt%. Grafted polyethylene with maleic anhydride (PE-g-MA) was used as a compatibilizer of the systems. PE and its systems were evaluated: XRD, TEM, TG and flammability (UL94HB, oxygen index (LOI) and cone calorimetry). The X-ray diffraction showed a partial intercalation and exfoliation as well as formation of microcomposite. The phase morphology of the systems was observed by TEM that it showed that the system with 1% OMMT clay presented a predominance of exfoliation. Already the system with 3% OMMT showed partial exfoliation and this exfoliation reduced as the clay content increased. By TG it was seen that MMT, OMMT and FRP acted improving the thermal behavior of the nanocomposites compared to PE matrix. The results obtained for the oxygen index showed that both PE and its systems presented flame retardancy behavior. By means of the horizontal flammability tests, it was found that the presence of 1% MMT clay reduced 25% the flammability of PE. By cone calorimetry it was found that the system that contains 9% of OMMT clay decreased by about 33% the flammability of PE.

scholarly journals Synthesis And Characterization Of CoMo/Mordenite Catalyst For Hydrotreatment Of Lignin Compound Models

2019 ◽  
Vol 17 (1) ◽  
pp. 1061-1070
Author(s):  
Khoirina Dwi Nugrahaningtyas ◽  
Nining Rahmawati ◽  
Fitria Rahmawati ◽  
Yuniawan Hidayat
Keyword(s):  
Electron Microscopy ◽  
Metal Content ◽  
Synthesis And Characterization ◽  
Impregnation Method ◽  
Total Acidity ◽  
X Ray Diffraction ◽  
Methyl Group ◽  
X Ray ◽  
Scanning Electron

AbstractThe synthesis of CoMo/Mordenite (CoMo/MOR) catalysts was conducted using a co-impregnation method at a various Co/Mo ratios. The produced catalysts were then characterized by X-ray diffraction, total acidity analysis, and scanning electron microscopy. The activity of the catalyst in a hydrotreatment reaction was evaluated by applying the catalyst as a reduced-catalyst to the hydrocracking (HC) reaction of anisole molecules. Analysis of the diffraction data using the Le Bail refinement technique showed that the metal phase was successfully impregnated into the MOR. In addition, increasing the metal content resulted in an increase in the acidity of the catalysts and changed the morphology of the catalysts from homogeneous to heterogeneous with larger particle size. According to the data of GCMS, it is known that the catalysts successfully removed methyl group of anisole molecules. Hydrotreatment reaction with the prepared-catalyst produced 4.77% of phenols. It is 122 % higher than the reaction with MOR catalyst.

scholarly journals Preparation of LDHs Based on Bittern and Its Flame Retardant Properties in EVA/LDHs Composites

2019 ◽  
Vol 2019 ◽  
pp. 1-13
Author(s):  
Long Li ◽  
Yi Qian ◽  
Peng Qiao ◽  
Haoyue Han ◽  
Haiming Zhang
Keyword(s):  
Flame Retardant ◽  
Ethylene Vinyl Acetate ◽  
Utilization Rate ◽  
Infrared Spectrometry ◽  
X Ray Diffraction ◽  
Limiting Oxygen Index ◽  
X Ray ◽  
Cone Calorimeter Test ◽  
Flame Retardant Properties ◽  
Double Hydroxides

Bittern, as a byproduct of salt manufacture, is abundant in China. The researches and developments for seawater bittern have mainly focused on the reuse of magnesium, calcium, lithium, and boron. However, the utilization rate is less than 20%. The large amount of unused bittern has become a challenge that attracts much attention in academic and industry areas. In this paper, three kinds of layered double hydroxides (LDHs) were synthesized from bittern using a coprecipitation method and characterized by X-ray diffraction (XRD). The XRD results showed that the three kinds of LDHs(MgAl-LDHs, MgFe-LDHs and MgAlFe-LDHs) were successfully synthesized. Then, the flame retardant properties and thermal properties of the three LDHs in ethylene vinyl acetate (EVA)/LDHs composites had been tested by cone calorimeter test (CCT), limiting oxygen index (LOI), smoke density test (SDT), and thermogravimetry-Fourier transform infrared spectrometry (TG-IR). The CCT results showed that the heat release rate (HRR) of all three kinds of EVA/LDHs composites significantly decreased compared with that of pure EVA, and the EVA/MgAl-LDHs composites had the lowest PHRR value of 222.65 kW/m2. The LOI results showed that EVA/MgAl-LDHs composites had the highest LOI value of 29.8%. The SDT results indicated that MgAl-LDHs were beneficial to smoke suppression. TG-IR results showed that EVA/MgAl-LDHs composites had a better thermal stability.

Synthesis of aluminum hydroxide thin coating and its influence on the thermomechanical and fire-resistant properties of wood

Holzforschung ◽  
2014 ◽  
Vol 68 (7) ◽  
pp. 781-789 ◽  
Author(s):  
Nana Wang ◽  
Yanchun Fu ◽  
Yongzhuang Liu ◽  
Haipeng Yu ◽  
Yixing Liu
Keyword(s):  
Reaction Time ◽  
Aluminum Hydroxide ◽  
Viscoelastic Properties ◽  
Oxygen Index ◽  
Reaction Times ◽  
X Ray Diffraction ◽  
Wood Substrate ◽  
Relative Crystallinity ◽  
Limiting Oxygen Index ◽  
X Ray

Abstract Aluminum hydroxide [Al(OH)3] film on wood substrate has been synthesized by means of the hydrothermal (HT) method for improvement of wood’s mechanical properties and resistance to combustion. The HT temperature was set to 100°C and 120°C, and the reaction time varied from 4 h to 10 h. X-ray diffraction (XRD) and X-ray photoelectron spectrometry (XPS) results show that the thin film grown on wood surface was amorphous Al(OH)3 and the relative crystallinity of treated woods slightly improved. SEM observation revealed that the Al(OH)3 film is composed of regular micro/nano-sized spheres, whose production and size increase with the reaction time, and some AlO(OH) structures emerged at 120°C with reaction times longer than 6 h. The storage modulus of the wood treated at 100°C and 120°C for 8 h can be improved by 30%, while the viscoelastic properties are also influenced by the HT treatment and Al(OH)3 coating. The limiting oxygen index of raw wood rose from 24.7% to 27.9% after the treatment, which can be interpreted as a moderate improvement of the fire resistance.

Development of a flame retardant chemical for finishing of cotton, polyester, and CO/PET blends

2018 ◽  
Vol 49 (2) ◽  
pp. 141-161 ◽  
Author(s):  
Raziye Atakan ◽  
Azize Bical ◽  
Ebru Celebi ◽  
Gulay Ozcan ◽  
Neda Soydan ◽  
...  
Keyword(s):  
Flame Retardant ◽  
Chemical Structure ◽  
Polyester Resin ◽  
Oxygen Index ◽  
Impregnation Method ◽  
Scanning Calorimetry ◽  
Limiting Oxygen Index ◽  
System A ◽  
Flammability Test ◽  
Flammability Characteristics

A novel polymeric flame retardant with phosphorous–nitrogen synergism (PVP (PR)-P-DCDA) was synthesized by polyvinyl alcohol, hydrophilic polyester resin, phosphoric acid, and dicyandiamide. 100% polyester, 100% cotton, and 50/50% cotton–polyester blended fabrics were treated with PVP (PR)-P-DCDA by impregnation method. Flammability characteristics, thermal decomposition, surface morphology, and chemical structure of treated and untreated fabrics were investigated by vertical flammability test, limiting oxygen index, differential scanning calorimetry, thermogravimetric analysis, scanning electron microscopy, and Fourier-transform infrared, respectively. Results showed that PVP (PR)-P-DCDA is an eco-friendly flame retardant system, a good char-forming flame retardant agent with superior ease of application for cotton, polyester, and cotton/polyester blends. At the industrial scale, the flame retardant agent PVP (PR)-PDCDA has been commercialized under the name Fire-off EBR.

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