Preparation and surface modification of Mg(OH)2/siloxane nanocomposite flame retardant

2015 ◽  
Vol 35 (2) ◽  
pp. 113-117 ◽  
Author(s):  
Qilei Wang
Keyword(s):  
Electron Microscopy ◽  
Flame Retardant ◽  
Flame Retardants ◽  
Specific Area ◽  
Composite Particles ◽  
Transmission Electron ◽  
Flame Retardant Properties ◽  
The Stability ◽  
Good Heat Resistance ◽  
Good Heat

Abstract In order to obtain flame retardants with good heat resistance, retardant properties and affinity, magnesium hydroxide (MH)/siloxane nanocomposite flame retardants were prepared by the hydrothermal and hypergravity method. The MH and MH/siloxane particles were characterized and analyzed by transmission electron microscopy (TEM), Brunner-Emment-Teller (BET) measurements, thermogravimetric analysis (TGA), etc. The results show that the stability of as-prepared MH/siloxane nanocomposite flame retardants is superior to MH particles prepared by other prepared methods, and the agglomeration is significantly reduced. The specific area of the composite particles was reduced, and the affinity and thermal stability were effectively improved. As a kind of filler for polymer, the MH/siloxane nanocomposite could help to improve the reinforcement of the polymer, and the heat resistant and flame retardant properties, which provide the foundation for further application of this nanocomposite as a flame retardant.

scholarly journals Preparation of Intercalated Organic Montmorillonite DOPO-MMT by Melting Method and Its Effect on Flame Retardancy to Epoxy Resin

Polymers ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 3496
Author(s):  
Junming Geng ◽  
Jianyu Qin ◽  
Jiyu He
Keyword(s):  
Electron Microscopy ◽  
Flame Retardant ◽  
Epoxy Resin ◽  
Flame Retardancy ◽  
Flame Retardants ◽  
Characterization Methods ◽  
Melting Method ◽  
Organic Montmorillonite ◽  
Ul 94 ◽  
Flame Retardant Properties

An intercalated organic montmorillonite DOPO-MMT was prepared through the melting method using 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) as a modifier. Epoxy resin (EP) composites were prepared with DOPO-MMT, DOPO, MMT, and the physical mixtures of DOPO+MMT as flame retardants. The microstructure of the flame retardants and EP samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The flame retardant properties, thermal stability, and residual char structure of the EPs were studied by the limited oxygen index (LOI) test, the UL-94 vertical burning test, thermogravimetric analysis (TGA), the differential scanning calorimeter (DSC) test, the cone calorimeter (CONE) test as well as other characterization methods. The results showed that the intercalated organic montmorillonite DOPO-MMT can be successfully prepared by the melting method and that the MMT is evenly dispersed in the EP/DOPO-MMT composite in the form of nanosheets. The EP/DOPO-MMT nanocomposites showed the optimal flame retardancy (LOI, UL-94, PHRR, etc.) among the EPs with DOPO, MMT, and the physical mixture of DOPO+MMT. The flame-retardant grade of the material reached V-0.

Properties of Flame-Retardant Cellulose Fibers Prepared from Cellulose[Amim]Cl Dope Solution

2011 ◽  
Vol 236-238 ◽  
pp. 1152-1155
Author(s):  
Lei Gao ◽  
Bo Wen Cheng ◽  
Jun Song ◽  
Zeng Geng Guo ◽  
Fei Lu ◽  
...  
Keyword(s):  
Flame Retardant ◽  
Flame Retardants ◽  
Simultaneous Thermal Analysis ◽  
Cellulose Fiber ◽  
Cellulose Fibers ◽  
Structure And Properties ◽  
Fiber Structure ◽  
Fiber Degradation ◽  
Dope Solution ◽  
Flame Retardant Properties

This paper has studied the structure and flame-retardant properties of flame-retardant cellulose fiber with DDPSN as flame retardant. The flame retardants was uniformly dispersed in the cellulose /[Amim]Cl Solution to obtain the good spinnable dope, then the dope was wet-spun. Effects of the flame-retardant contention the fiber structure and properties were investigated. The surface of the flame-retardant cellulose fiber was observed using field emission scanning electron microscope (FESEM). Besides, through the Simultaneous thermal analysis, it has been shown that, with the increase of fame retardant, the degree of fame resistance was obviously improved. The flame retardant acted greatly in condensed phase during the fiber degradation and remained mainly in residues after degradation, the experiments show that the flame-retardant properties of flame-retardant cellulose fiber with 20wt% DDPSN was obvious.

Wool: Its Effect On Flame Retardant Properties of Blend Fabrics

1983 ◽  
Vol 1 (2) ◽  
pp. 145-154 ◽  
Author(s):  
John V. Beninate ◽  
Brenda J. Trask ◽  
Timothy A. Calamari ◽  
George L. Drake
Keyword(s):  
Thermal Degradation ◽  
Flame Retardant ◽  
Flame Retardants ◽  
Oxygen Index ◽  
Cotton Fabrics ◽  
Cotton Wool ◽  
Burning Rates ◽  
Low Levels ◽  
Flame Retardant Properties ◽  
Strength Retention

Durable phosphorus-based flame retardants were applied to twill fabrics con taining cotton and wool to study the effect of wool on the flame retardancy and physical properties of the blend fabrics. The presence of wool in untreated blend fabrics caused burning rates to decrease and oxygen index values to increase as wool content increased in the blends. These effects were also observed in cotton/ wool blends treated with low levels of the Thps-urea-TMM flame retardant, but were less pronounced in fabrics treated at high levels. Thermogravimetric analyses were conducted to study the thermal degradation of the treated and untreated fabrics. The presence of wool in treated blend fabrics did not sig nificantly change strength retention, area shrinkage and wrinkle recovery values in comparison to similarly treated 100% cotton fabrics.

scholarly journals Improving stability of cerium oxide nanoparticles by microbial polysaccharides coating

2018 ◽  
Vol 83 (6) ◽  
pp. 745-757 ◽  
Author(s):  
Ivana Milenkovic ◽  
Ksenija Radotic ◽  
Branko Matovic ◽  
Marija Prekajski ◽  
Ljiljana Zivkovic ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Cerium Oxide ◽  
Aqueous Media ◽  
Suspension Stability ◽  
X Ray Diffraction ◽  
Synthesis Conditions ◽  
Transmission Electron ◽  
Ft Ir ◽  
Microbial Exopolysaccharides ◽  
The Stability

Cerium oxide (CeO2) nanoparticles (CONPs) are interesting biomaterials with various applications in biomedicine, cosmetics and the pharmaceutical industry, but with limited practical application because of their low stability in aqueous media. The aim of this study was to obtain CONPs with increased stability by coating the particles. Microbial exopolysaccharides (levan, pullulan) and glucose were used to prepare CONPs under different synthesis conditions. Coating was attempted by adding the carbohydrates during (direct coating) or after (subsequent coating) the synthesis of CONPs. The obtained nanoparticles were characterized by X-Ray diffraction analysis, Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The suspension stability of the uncoated and coated CONPs in aqueous media was evaluated by measuring the hydrodynamic size, zeta potential and turbidity. The FT-IR spectra revealed the differences between coated CONPs and showed the success of subsequent coating with carbohydrates. Coating with carbohydrates improved the stability the CONP suspension by decreasing the size of aggregated particles. The suspensions of levan- and glucose-coated CONPs had the best stability. In this study, CONPs were prepared using non-toxic materials, which were completely environmentally friendly. The obtained results open new horizons for CONP synthesis, improving their biological applications.

scholarly journals SILVER NANOPARTICLES FROM MEDICINALLY IMPORTANT EUPHORBIA CYATHOPHORA EXTRACT: BIOSYNTHESIS, CHARACTERIZATION, AND ANTICANCER ACTIVITY.

2018 ◽  
Vol 11 (2) ◽  
pp. 154
Author(s):  
Robert Lotha ◽  
Aravind Sivasubramanian ◽  
Meenakshi Sundaram Muthuraman
Keyword(s):  
Electron Microscopy ◽  
Silver Nanoparticles ◽  
Cell Line ◽  
Aqueous Extract ◽  
Visible Spectroscopy ◽  
X Ray ◽  
Transmission Electron ◽  
The Stability ◽  
Ht 29 ◽  
Scanning Electron

Objective: The present study was aimed at the biosynthesis of silver nanoparticles (AgNPs) using aqueous extract of Euphorbia cyathophora leavesand testing their anticancer potential using HT-29 cell line model.Methods: Green synthesis of silver nanoparticles was obtained with the aqueous extract of E. cyathophora. The synthesized nanoparticles wereconfirmed initially by ultraviolet-visible spectroscopy. Further, scanning electron microscopy, transmission electron microscopy, and X-Ray diffractionstudies also ensured the presence of silver nanoparticles. Zeta potential studies revealed the stability of the silver nanoparticles.Results: Antioxidant and anticancer studies of the nanoparticles against HT-29 cell line exhibited remarkable results.Conclusion: This ensures that the synthesized nanoparticles play an important role in medicinal biology.

Structure, Composition and Stability of Heterophase Boundaries

1997 ◽  
Vol 3 (S2) ◽  
pp. 673-674
Author(s):  
M. Rühle ◽  
T. Wagner ◽  
S. Bernath ◽  
J. Plitzko ◽  
C. Scheu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Elevated Temperatures ◽  
Analytical Electron Microscopy ◽  
High Resolution Electron Microscopy ◽  
Advanced Materials ◽  
Bulk Crystals ◽  
Transmission Electron ◽  
Resolution Electron ◽  
The Stability

Heterophase boundaries play an important role in advanced materials since those materials often comprise different components. The properties of the materials depend strongly on the properties of the interface between the components. Thus, it is important to investigate the stability of the microstructure with respect to annealing at elevated temperatures. In this paper results will be presented on the structure and composition of the interfaces between Cu and (α -Al2O3. The interfaces were processed either by growing a thin Cu overlayer on α- Al2O3 in a molecular beam epitaxy (MBE) system or by diffusion bonding bulk crystals of the two constituents in an UHV chamber. To improve the adhesion of Cu to α -Al2O3 ultrathin Ti interlayers were deposited between Cu and α - Al2O3.Interfaces were characterized by different transmission electron microscopy (TEM) techniques. Quantitative high-resolution electron microscopy (QHRTEM) allows the determination of the structure (coordinates of atoms) while analytical electron microscopy (AEM) allows the determination of the composition with high spatial resolution.

Flammability and mechanical properties of poly(styrene–butadiene–styrene) copolymer–containing intumescent flame retardants

2015 ◽  
Vol 30 (6) ◽  
pp. 816-826 ◽  
Author(s):  
Yiren Huang ◽  
Jianwei Yang ◽  
Zhengzhou Wang
Keyword(s):  
Mechanical Properties ◽  
Flame Retardant ◽  
Flame Retardants ◽  
Oxygen Index ◽  
Limiting Oxygen Index ◽  
Styrene Butadiene Styrene ◽  
Flame Retardant Properties ◽  
Intumescent Flame Retardants ◽  
Styrene Butadiene ◽  
Butadiene Styrene

Flame-retardant properties of ammonium polyphosphate (APP) and its two microcapsules, APP with a shell of melamine–formaldehyde (MF) resin (MFAPP) and APP with a shell of epoxy resin (EPAPP), were studied in styrene–butadiene–styrene (SBS). The results indicate that APP after the microencapsulation leads to an increase in limiting oxygen index in SBS compared with APP. When dipentaerythritol is incorporated into the SBS composites containing the APP microcapsules, a further improvement in flame retardancy of the composites is observed. The microencapsulation does not result in much improvement of mechanical properties. Moreover, the effect of a compatibilizer (SBS grafted with maleic anhydride) on flame-retardant and mechanical properties of SBS/APP composites was investigated.

The Effect of Interfacial Free Energies on the Stability of Microlaminates

2000 ◽  
Vol 652 ◽  
Author(s):  
A. C. Lewis ◽  
A. B. Mann ◽  
D. van Heerden ◽  
D. Josell ◽  
T. P. Weihs
Keyword(s):  
Electron Microscopy ◽  
Grain Boundary ◽  
High Temperatures ◽  
Free Energies ◽  
Microstructural Stability ◽  
Creep Tests ◽  
Interfacial Energies ◽  
Transmission Electron ◽  
The Stability ◽  
Interfacial Free Energies

ABSTRACTLaminated composites with polycrystalline layers typically break down at high temperatures through grain boundary grooving and the pinch-off of individual layers. Such materials, when exposed to high temperatures, develop grooves where grain boundaries meet the interfaces between layers. The depths of the grooves are controlled by the ratios of grain boundary and interfacial free energies, γgb/γint. Depending on the dimensions of the grains, these grooves can extend through the entire layer, causing pinch-off at the grain boundary. This pinch-off destroys the layering and eventually leads to a gross coarsening of the microstructure. Because microstructural stability is critical to performance for most applications, the ability to understand and predict the stability of microlaminates is a necessary tool. An existing model of this capillarity-driven breakdown requires the interfacial free energies, γgb and γint, as input parameters. Both biaxial and uniaxial zero creep tests have been used in conjunction with transmission electron microscopy to measure these interfacial energies in Ag/Ni and Nb/Nb5Si3 microlaminates.

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