scholarly journals Preparation of β-Cyclodextrin Inclusion Complex and Its Application as an Intumescent Flame Retardant for Epoxy

Polymers ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 71 ◽  
Author(s):  
Xueying Shan ◽  
Kuanyu Jiang ◽  
Jinchun Li ◽  
Yan Song ◽  
Ji Han ◽  
...  
Keyword(s):  
Carbon Source ◽  
Inclusion Complex ◽  
Flame Retardant ◽  
1H Nmr ◽  
Intumescent Flame Retardant ◽  
Molar Ratio ◽  
Gravimetric Analysis ◽  
X Ray ◽  
Cone Calorimeter Test ◽  
The Impact

A new P-N containing the flame retardant, which was namely N,N′-dibutyl-phosphate diamide (DBPDA), was synthesized and it was assembled into the cavity of β-cyclodextrin (β-CD) to form an inclusion complex (IC). The structure and properties of IC were characterized by Fourier transform infraredspectroscopy (FTIR), wide-angle X-ray diffraction (WAXD), 1H nuclear magnetic resonance (1H NMR), scanning electron microscopy with X-ray microanalysis (SEM-EDS), differential scanning calorimeter (DSC) and thermal gravimetric analysis (TGA). 1H NMR and SEM-EDS were also used to identify the molar ratio of β-CD/DBPDA in IC and the results from the analyses indicated that their molar ratio was 1:1. In order to test the flame retardant effect of IC, it was added to epoxy (EP). IC was proposed to be able to act as an intumescent flame retardant (IFR) system in EP through a combination of β-CD and DBPDA properties during the combustion process. β-CD is a biomass carbon source, which has the advantages of environmental protection and low cost. Furthermore, DBPDA is both a source of acid and gas. When IC was heated, IC had the advantage of acting as both a carbon source and foam forming agent, while the DBPDA component were able to directly generate phosphoric acid and NH3 in situ. The impact of IC in low additive amounts on flame retardancy of EP was studied by the cone calorimeter test. When only 3 wt % IC was incorporated, the peak values of heat release rate (pHRR) and smoke production rate (pSPR) of EP were reduced by 22.9% and 33.3% respectively, which suggested that IC could suppress the heat and smoke release efficiently.

scholarly journals Synthesis of Phosphated K-Carrageenan and Its Application for Flame-Retardant Waterborne Epoxy

Polymers ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 1268 ◽  
Author(s):  
Na Wang ◽  
Haiwei Teng ◽  
Long Li ◽  
Jing Zhang ◽  
Ping Kang
Keyword(s):  
Flame Retardant ◽  
Flame Retardancy ◽  
Photoelectron Spectroscopy ◽  
Thermo Gravimetric Analysis ◽  
Gravimetric Analysis ◽  
Mass Ratio ◽  
Thermo Gravimetric ◽  
X Ray ◽  
Cone Calorimeter Test ◽  
Waterborne Epoxy

In this paper, phosphated K-carrageenan (P-KC) was obtained by reacting POCl3 with the renewable source K-carrageenan (KC). P-KC and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) were added into waterborne epoxy (EP) to improve its flame retardancy. The structure of P-KC was studied comprehensively using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), thermo-gravimetric analysis (TGA), showing the successful synthesis of P-KC. The flame retardancy of the EP was evaluated by the cone calorimeter test. The results showed that different mass ratios of DOPO and P-KC affected the flame retardancy of EP. When the mass ratio of DOPO and P-KC was 2:1, total heat release (THR) and total smoke production (TSP) decreased by 48.7% and 37.4%, respectively. The microstructures of residue char were observed by FTIR and scanning electron microscopy (SEM), indicating that the flame-retardant waterborne epoxy (FR-EP) system held a more cohesive and denser char structure. The char inhibited the diffusion of heat and oxygen, which played a key role in the flame retardancy.

scholarly journals Synthesis of Novel Arginine-Based Flame Retardant and Its Application in Lyocell Fabric

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3588
Author(s):  
Jiayi Chen ◽  
Yansong Liu ◽  
Jiayue Zhang ◽  
Yuanlin Ren ◽  
Xiaohui Liu
Keyword(s):  
Fourier Transform ◽  
Heat Release ◽  
Flame Retardant ◽  
Photoelectron Spectroscopy ◽  
Fourier Transform Infrared ◽  
Ftir Analysis ◽  
Excellent Thermal Stability ◽  
X Ray ◽  
Cone Calorimeter Test ◽  
Before And After

Lyocell fabrics are widely applied in textiles, however, its high flammability increases the risk of fire. Therefore, to resolve the issue, a novel biomass-based flame retardant with phosphorus and nitrogen elements was designed and synthesized by the reaction of arginine with phosphoric acid and urea. It was then grafted onto the lyocell fabric by a dip-dry-cure technique to prepare durable flame-retardant lyocell fabric (FR-lyocell). X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FTIR) analysis demonstrated that the flame retardant was successfully introduced into the lyocell sample. Thermogravimetric (TG) and Raman analyses confirmed that the modified lyocell fabric featured excellent thermal stability and significantly increased char residue. Vertical combustion results indicated that FR-lyocell before and after washing formed a complete and dense char layer. Thermogravimetric Fourier-transform infrared (TG-FTIR) analysis suggested that incombustible substances (such as H2O and CO2) were produced and played a significant fire retarding role in the gas phase. The cone calorimeter test corroborated that the peak of heat release rate (PHRR) and total heat release (THR) declined by 89.4% and 56.4%, respectively. These results indicated that the flame retardancy of the lyocell fabric was observably ameliorated.

scholarly journals Role of Copper Oxide on Epoxy Coatings with New Intumescent Polymer-Based Fire Retardant

Molecules ◽  
2020 ◽  
Vol 25 (24) ◽  
pp. 5978
Author(s):  
Riyazuddin ◽  
Samrin Bano ◽  
Fohad Mabood Husain ◽  
Jamal Akhter Siddique ◽  
Khadijah H. Alharbi ◽  
...  
Keyword(s):  
Copper Oxide ◽  
Heat Release ◽  
Flame Retardant ◽  
Cone Calorimeter ◽  
Elevated Temperatures ◽  
Fire Retardant ◽  
Intumescent Flame Retardant ◽  
Gravimetric Analysis ◽  
Sem Images ◽  
Major Drawback

Epoxy resins (EP) have been used as a thermos-setting material in the field of coating, casting, bonding agent, and laminating. However, a major drawback associated with its use is the lack of good flaming properties, and it is responsible for heavy smoke along with hazardous gases considerably limiting its uses in various fields. In this study, N-ethanolamine triazine-piperizine, a melamine polymer (ETPMP), was established as a new charring-foaming agent and was successfully synthesized with ethanolamine, piperizine, cyanuric chloride, and melamine as precursor molecules via the nucleophilic substitution reaction method. Elemental analysis and Fourier transform infrared (FTIR) spectroscopy analysis were applied to approve the synthesis of ETPMP and confirmation of its structure and characterization. The epoxy coating of intumescent flame retardant (IFR) was equipped by introducing ETPMP, ammonium polyphosphate (APP), and copper oxide (CuO) in multiple composition ratios. CuO was loaded at various amounts into the IFR-coating system as a synergistic agent. The synergistic action of CuO on IFR coatings was scientifically examined by using different analytical tests such as vertical burning test (UL-94V), limited oxygen index (LOI), thermal gravimetric analysis (TGA), cone calorimeter, and scanning electron microscope (SEM). The results showed that small changes in the amount of CuO expressively amplified the LOI results and enhanced the V-0 ratings in the UL-94V test. The TGA data clearly demonstrate that the inclusion of CuO can transform the thermal deprivation behavior of coatings with a growing char slag proportion with elevated temperatures. Information from cone calorimeter data affirmed that CuO can decrease the burning factors by total heat release (THR) together with peak heat release rate (PHRR). The SEM images indicated that CuO can enrich the power and compression of the intumescent char that restricts the movement of heat and oxygen. Our results demonstrate a positive influence of CuO on the epoxy-headed intumescent flame retardant coatings.

Thermal and Chemical Stability of Micron Aluminum Powders Subjected to Gaseous Water

2016 ◽  
Vol 712 ◽  
pp. 241-245
Author(s):  
Sergey V. Zmanovskiy ◽  
Alexander M. Gromov ◽  
Valentina V. Smirnova ◽  
Vadim F. Petrunin ◽  
Jin Chun Kim
Keyword(s):  
Room Temperature ◽  
Gravimetric Analysis ◽  
X Ray Diffraction ◽  
Aluminum Powders ◽  
X Ray ◽  
The Stability ◽  
Heating Up ◽  
The Impact ◽  
Thermal And Chemical Stability ◽  
Composition Of Products

The paper studies the impact of gaseous water on the stability of micron aluminum powders in time at room temperature using the method of gravimetric analysis. The stability was studied using methods of thermal analysis during heating up to 1200 °С in air. The composition of products was analyzed using X-ray diffraction analysis. It was found out that the stability of micron aluminum powders depends on partial pressure of water vapor: the increase of pressure results in decreased stability of powders. The work gives recommendations for storing micron aluminum powders.

scholarly journals β-Cyclodextrin as a Functional Excipient Used for Enhancing the Diminazene Aceturate Bioavailability

Pharmaceutics ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 295 ◽  
Author(s):  
Narcisa Marangoci ◽  
Daniel Timpu ◽  
Andreia Corciova ◽  
Cornelia Mircea ◽  
Anca-Roxana Petrovici ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Inclusion Complex ◽  
Blood Plasma ◽  
1H Nmr ◽  
Molar Ratio ◽  
Variation Method ◽  
In Vitro Tests ◽  
Diminazene Aceturate

In this study, we proposed formulations of diminazene aceturate (DA) designed to improve its bioavailability and to maximize the therapeutic index in animals by overcoming the rapid degradation under the acidic pH of the stomach. An important consequence is the fact that its amount in the bloodstream is close to the administered dose. This was made possible by incorporating DA into the β-cyclodextrin’s (βCD) cavity in a molar ratio of 1:1. The structure of the resulted inclusion complex was established by Raman, DSC, and Wide-Angle X ray Diffraction (WAXD) in solid state and by 1H-NMR and H-H ROESY in aqueous solutions. The stoichiometry of the DA:βCD inclusion complex was obtained by using the continuous variation method (Job’s plot), considering the chemical shifts variations of protons from both DA and βCD compounds in 1H-NMR spectra. The biological activity was estimated in vitro by antioxidant activity and in vivo by comparing the bioavailability of parent DA and its inclusion complexes after a single dose administration in Wistar rats by using the HPLC method on their blood plasma. In vitro tests showed an improved antioxidant activity. In vivo tests have shown that the DA concentration is always much higher in blood plasma of rats when DA:βCD inclusion complex of 1:1 molar ratio was administered (i.e., at 60 min, DA is around 11 and 3 times higher when DA:βCD inclusion complex of 1:1 molar ratio was administered than the parent DA one and DA:βCD lyophilized mixture of 1:2 molar ratio, respectively).

Alkali Lignin as a Carbonization Agent on the Thermal Degradation and Flame Retardancy of Intumescent Flame Retardant Coating

2013 ◽  
Vol 750-752 ◽  
pp. 1385-1388 ◽  
Author(s):  
Li Yong Jiao ◽  
Zheng Jie Wu
Keyword(s):  
Thermal Degradation ◽  
Flame Retardant ◽  
Flame Retardancy ◽  
Cone Calorimeter ◽  
Intumescent Flame Retardant ◽  
Thermal Stabilities ◽  
Alkali Lignin ◽  
Blowing Agent ◽  
Cone Calorimeter Test ◽  
Peak Heat Release Rate

The influence of alkali lignin (AL) as a carbonization agent on the thermal degradation and flame retardancy of intumescent flame retardant (IFR) coating was investigated under air condition, with ammonium polyphosphate (APP) as an acid source, and melamine (MEL) as a blowing agent. Compared with a traditional APP/pentaerythritol (PER) /MEL IFR system, thermogravimetric analysis (TGA) results showed that APP/AL/MEL IFR system could induce the synergistic effect at a much boarder temperature range, and improve the thermal stabilities of the IFR coating. With the increase of AL loading, cone calorimeter test showed the peak heat release rate of the IFR coatings decreased from 54.86 MJ/m2to 41.06 MJ/m2.

scholarly journals The impact of pressure on β-Cyclodextrin·acetaminophen inclusion complexes

2014 ◽  
Vol 70 (a1) ◽  
pp. C264-C264 ◽  
Author(s):  
Sofiane Saouane ◽  
Wolfgang Morgenroth ◽  
Hanns-Peter Liermann ◽  
Carsten Paulmann ◽  
Francesca Fabbiani
Keyword(s):  
High Pressure ◽  
Inclusion Complex ◽  
Aqueous Solubility ◽  
Crystal Form ◽  
Model Systems ◽  
X Ray Diffraction ◽  
X Ray ◽  
Pharmaceutical Ingredients ◽  
The Impact

Cyclodextrins (CDs) have attracted considerable interest as model systems in supramolecular host-guest chemistry. They are described as hollow truncated cones with a hydrophilic outer surface and a nonpolar inner cavity suitable for small molecules' encapsulation.[1] By virtue of their character, CDs are used as excipients to improve the aqueous solubility of active pharmaceutical ingredients (APIs). High-pressure crystallisation techniques have been established as a suitable tool for exploring the phenomenon of polymorphism and solvate formation of pharmaceutical compounds throughout numerous examples reported in the literature.[2] Thus, exploring the inclusion-complex formation and the polymorphic behaviour of CDs with APIs at high pressure would be an interesting extension of the technique. The present work describes the attempt of an in-situ crystallisation of β-CD·acetaminophen inclusion complex and compression studies of the known β-CD·acetaminophen complex[3] in different crystallisation media at pressures up to 1.0 GPa. A new high-pressure crystal form observed at 0.8 GPa as well as unexpected results are presented herein. The crystals have been characterised by means of polarised optical microscopy, Raman spectroscopy and single-crystal X-ray diffraction using both home and synchrotron sources.

Synthesis of LNF Nano Particles for Fuel Cell Applications

2009 ◽  
Vol 1230 ◽  
Author(s):  
Reza Bateni ◽  
Maryan Nasirpour ◽  
Olivera Kesler
Keyword(s):  
Ph Value ◽  
Thermo Gravimetric Analysis ◽  
Combustion Process ◽  
Precursor Solution ◽  
Nano Particles ◽  
Process Efficiency ◽  
Molar Ratio ◽  
Gravimetric Analysis ◽  
Metallic Ions ◽  
X Ray

AbstractThe aim of the present work is to understand the effect of different parameters such as the molar ratio of metallic ions to fuel in sol-gel solution, pH of the solution, and calcining temperature on the efficiency of the combustion synthesis technique in preparing submicron lanthanum nickel ferrite using metal nitrate-citrate/glycine mixtures. Scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDS) was used to evaluate the powder morphology and elemental composition. The crystal structure of the calcined powders was evaluated by X-ray diffraction (XRD) and the thermal characteristics of the LNF precursors were examined by thermo-gravimetric analysis (TGA) in air, to identify suitable processing conditions. It was found that by increasing the molar ratio of fuel to metallic ions in the precursor solution, calcining could take place at lower temperatures. However, by increasing the molar ratio of fuel to metallic ions, the yield of the combustion process was decreased. Furthermore, the pH value of the precursor solution did not have any influence on the process efficiency over the range examined.

scholarly journals Synergistic Action of Montmorillonite with an Intumescent Formulation: The Impact of the Nature and the Strength of Acidic Sites on the Flame-Retardant Properties of Polypropylene Composites

Polymers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 2781
Author(s):  
Raíssa Carvalho Martins ◽  
Michelle Jakeline Cunha Rezende ◽  
Marco Antonio Chaer Nascimento ◽  
Regina Sandra Veiga Nascimento ◽  
Simone Pereira da Silva Ribeiro
Keyword(s):  
Flame Retardant ◽  
Nitrogen Adsorption ◽  
Synergistic Action ◽  
Limit Oxygen Index ◽  
Esterification Reaction ◽  
X Ray ◽  
Polypropylene Composites ◽  
Acidic Sites ◽  
Flame Retardant Properties ◽  
The Impact

A raw montmorillonite (Mt) was submitted to different acidic activation times in order to investigate the influence of the strength and the nature (Brønsted and Lewis) of acidic sites on the synergistic action with an intumescent formulation (IF) composed of ammonium polyphosphate (APP) and pentaerythritol (PER) when incorporated into a polypropylene (PP) matrix. The acidity of the Mt samples was quantified by ammonia temperature-programmed desorption (TPD-NH3) and Fourier transform infrared spectroscopy (FTIR) with pyridine adsorption. The mineral clays were also characterized by X-ray fluorescence (XRF), X-ray diffraction (XRD), nitrogen adsorption analysis and particle size distribution. Thermogravimetric analysis (TGA), limit oxygen index (LOI) and UL-94 were performed to evaluate the flame-retardant properties and the thermal stability. The TGA results show that the final residue increased 2 to 3 fold in comparison to the values predicted theoretically. The flammability properties achieved a maximum for the system containing an excess of moderate-strength Brønsted sites relative to the Lewis ones, reaching 38% in the LOI test. This result suggests that the presence of these Brønsted acidic sites is important, as they take part in the esterification reaction between APP and PER which gives rise to the char formation. The FTIR-Pyr adsorption and flammability results indicate that both the nature and strength of the acidic sites influence the flame-retardant properties.

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