Synergistic effect of carbon nanotubes in combination with magnesium hydroxide on the flame retardant poly(ethylene-co-vinyl acetate)

2016 ◽  
Vol 23 (1) ◽  
pp. 29-35 ◽  
Author(s):  
Hongyan Li ◽  
Hongli Liu ◽  
Junwei Li ◽  
Sen Tao ◽  
Jing Li ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Synergistic Effect ◽  
Flame Retardant ◽  
Vinyl Acetate ◽  
Magnesium Hydroxide ◽  
X Ray Diffraction ◽  
Cone Calorimetry ◽  
Transmission Electron ◽  
Poly Ethylene ◽  
20 Nm

AbstractTo investigate the synergistic effect of carbon nanotubes (CNTs) in combination with magnesium hydroxide (MH) on the flame retardant poly(ethylene-co-vinyl acetate) (EVA), a series of EVA-based composites filled with CNTs, MH, a mixture of MH and CNTs, and MH-modified CNTs (MH-CNTs) were prepared. Characterizations of the fillers and the composites were performed by transmission electron microscopy, X-ray diffraction, Raman spectroscopy, thermogravimetric analysis, and cone calorimetry. The results indicated that the presence of CNTs affected the size of the attaching MH, which was decreased to around 20 nm. MH also had an enlarged special surface area in the MH-CNTs. A synergism was found in the MH-CNTs on the thermal retardant EVA composites due to the interaction between MH and CNTs.

The High Thickness Ni Layer on Single-Walled Carbon Nanotubes Prepared by an Electroless Coating Process

2010 ◽  
Vol 148-149 ◽  
pp. 1607-1610
Author(s):  
Wei Xue Li ◽  
Dun Dong Wang ◽  
Hui Jin ◽  
Jian Feng Dai ◽  
Qing Wang
Keyword(s):  
Carbon Nanotubes ◽  
Single Walled Carbon Nanotubes ◽  
Deposition Process ◽  
X Ray Diffraction ◽  
Electroless Coating ◽  
Single Walled Carbon ◽  
Selected Area Electron Diffraction ◽  
Transmission Electron ◽  
20 Nm ◽  
Walled Carbon Nanotubes

The Single-walled carbon nanotubes were coated with Ni-P layers by an electroless plating technique. A Ni-P layers are thick and smooth and on individual nanotube with thickness of 20 nm can be obtained after the deposition process. The Single-walled carbon nanotubes were obtained in the suspension of purification solution. The samples have been characterized by X-ray diffraction, selected area electron diffraction, transmission electron microscopy and energy dispersive spectrometry.The coating layers after heat-treatment convert the amorphous Ni-P coated layers into the nanocrystalline Ni-P layers.

scholarly journals Enhanced Flame Retardancy in Ethylene–Vinyl Acetate Copolymer/Magnesium Hydroxide/Polycarbosilane Blends

Polymers ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 36
Author(s):  
Tiefeng Zhang ◽  
Chunfeng Wang ◽  
Yongliang Wang ◽  
Lijun Qian ◽  
Zhidong Han
Keyword(s):  
Synergistic Effect ◽  
Flame Retardant ◽  
Vinyl Acetate ◽  
Magnesium Hydroxide ◽  
Ethylene Vinyl Acetate ◽  
Infrared Spectrometry ◽  
Limiting Oxygen Index ◽  
Blending Method ◽  
Acetate Copolymer ◽  
Ethylene Vinyl Acetate Copolymer

A polymer ceramic precursor material—polycarbosilane (PCS)—was used as a synergistic additive with magnesium hydroxide (MH) in flame-retardant ethylene–vinyl acetate copolymer (EVA) composites via the melt-blending method. The flame-retardant properties of EVA/MH/PCS were evaluated by the limiting oxygen index (LOI) and a cone calorimeter (CONE). The results revealed a dramatic synergistic effect between PCS and MH, showing a 114% increase in the LOI value and a 46% decrease in the peak heat release rate (pHRR) with the addition of 2 wt.% PCS to the EVA/MH composite. Further study of the residual char by scanning electron microscopy (SEM) proved that a cohesive and compact char formed due to the ceramization of PCS and close packing of spherical magnesium oxide particles. Thermogravimetric analysis coupled with Fourier-transform infrared spectrometry (TG–FTIR) and pyrolysis–gas chromatography coupled with mass spectrometry (Py–GC/MS) were applied to investigate the flame-retardant mechanism of EVA/MH/PCS. The synergistic effect between PCS and MH exerted an impact on the thermal degradation products of EVA/MH/PCS, and acetic products were inhibited in the gas phase.

scholarly journals Synergistic flame-retardant effect between lignin and magnesium hydroxide in poly(ethylene-co-vinyl acetate)

2019 ◽  
Vol 2 (1) ◽  
pp. 9-18 ◽  
Author(s):  
Fouad Laoutid ◽  
Victor Duriez ◽  
Loic Brison ◽  
Sabrina Aouadi ◽  
Henri Vahabi ◽  
...  
Keyword(s):  
Chemical Modification ◽  
Flame Retardant ◽  
Vinyl Acetate ◽  
Magnesium Hydroxide ◽  
Cone Calorimeter ◽  
Fire Behavior ◽  
Ammonium Phosphate ◽  
Endothermic Effect ◽  
Cone Calorimeter Test ◽  
Poly Ethylene

AbstractIn this study, we evaluated the interest of combining magnesium hydroxide (MDH) and lignin for developing complementary flame retardant actions in poly(ethylene-co-vinyl acetate) (EVA). Lignin was selected owing to its char forming ability thatwas supposed to reinforce the endothermic effect provided by MDH. The effect of lignin chemical modification by ammonium phosphate functions also evaluated as a way for enhancing its charring effect. Fire properties and thermal behavior of EVA composites were characterized using cone calorimeter, Pyrolysis Combustion Flow Calorimeter (PCFC) and thermogravimetric analysis (TGA). The effect of the incorporation of lignin alone on EVAcomposite thermal and fire behavior first evaluated. Results evidenced that the incorporation of lignin, whatever its nature, induced important reduction of composite thermal stability during TGA analysis as well as significant reduction of the time to ignition (TTI) in cone calorimeter test. However, a significant reduction of peak of heat release rate (pHRR), higher than that obtained with MDH was observed. The combination of lignin and MDH was led to further reduction of pHRR. Furthermore, it was concluded that the chemical modification of lignin is not required prior obtaining improved flame-retardant properties.

Flame Retardant Polyamide 6 Composites Using NMH or NMH/MCA/APP

2011 ◽  
Vol 189-193 ◽  
pp. 1208-1211 ◽  
Author(s):  
Yan Shen ◽  
Shao Guo Wen ◽  
Ji Hu Wang ◽  
Hong Bo Liu ◽  
Hai Liang Qi ◽  
...  
Keyword(s):  
Flame Retardant ◽  
Magnesium Hydroxide ◽  
Flame Retardants ◽  
Polyamide 6 ◽  
X Ray Diffraction ◽  
Upward Trend ◽  
Orthorhombic Crystal ◽  
Orthorhombic Crystal Structure ◽  
Orthogonal Experiments ◽  
Nitrogen Phosphorus

In this paper, flame retardant Polyamide 6 (PA6) composites were prepared by nano-magnesium hydroxide (NMH) or its composites with melamine cyanurate(MCA) and ammonium polyphosphate(APP). Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to analyze the structure of nano-magnesium hydroxide. The properties including tensile properties, molten index (MFI), rockwell hardness and density of flame retardant PA6 were analyzed. Orthogonal experiments were used to study flame retardancy of PA6 with NMH, MCA and APP. The results showed NMH had hexagonal orthorhombic crystal structure with size of 300×200×100nm. Density of polyamide 6 showed an upward trend when the content of NMH was increasing, the mechanical properties and hardness changed little while processing performance serious declined. The flame retardance of nitrogen-phosphorus -inorganic flame retardants was not desirable.

scholarly journals Study Structure and Properties of Nanocomposite Material Based on Unsaturated Polyester with Clay Modified by Poly(ethylene oxide)

2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
Tran Duy Thanh ◽  
Nguyen Dang Mao ◽  
Nguyen Thi Kim Ngan ◽  
Ha Thuc Chi Nhan ◽  
Ha Thuc Huy ◽  
...  
Keyword(s):  
Ethylene Oxide ◽  
Polymer Matrix ◽  
Unsaturated Polyester ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Poly Ethylene Oxide ◽  
Hydrophobic Nature ◽  
Poly Ethylene ◽  
Alkyl Ammonium

In recent years, polymer clay nanocomposites have been attracting considerable interests in polymers science because of their advantages. There are many scientists who researched about this kind of material and demonstrated that when polymer matrix was added to little weight of clay, properties were enhanced considerably. Because clay is a hydrophilic substance so it is difficult to use as filler in polymer matrix having hydrophobic nature, so clay needs to be modified to become compatible with polymer. In this study, poly(ethylene oxide) was used as a new modifier for clay to replace some traditional ionic surfactants such as primary, secondary, tertiary, and quaternary alkyl ammonium or alkylphosphonium cations having the following disadvantages: disintegrate at high temperature, catalyze polymer degradation, and make nanoproducts colorific, and so forth. In order to evaluate modifying effect of poly(ethylene oxide), modified clay products were characterize d by X-ray spectrum. Then organoclay was used to prepare nanocomposite based on unsaturated polyester. Morphology and properties of nanocomposites were measure d by X-ray diffraction, transmission electron microscopy, tensile strength, and thermal stability. The results showed that clay galleries changed to intercalated state in the nanocomposites. Properties of nanocomposites were improved a lot when the loading of the organoclay was used at 1 phr.

scholarly journals Role of Surfactants in the Properties of Poly(Ethylene Terephthalate)/Purified Clay Nanocomposites

Materials ◽  
2018 ◽  
Vol 11 (8) ◽  
pp. 1397 ◽  
Author(s):  
Elaine dos Santos ◽  
Marcus Fook ◽  
Oscar Malta ◽  
Suédina de Lima Silva ◽  
Itamara Leite
Keyword(s):  
Clay Nanocomposites ◽  
Phosphonium Salts ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Transmission Electron ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene ◽  
Alkyl Ammonium ◽  
Pet Crystallization

Purified clay was modified with different amounts of alkyl ammonium and phosphonium salts and used as filler in the preparation of PET nanocomposites via melt intercalation. The effect of this type of filler on morphology and thermal and mechanical properties of PET nanocomposites was investigated by X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analyses (TG), tensile properties, and transmission electron microscopy (TEM). The results showed that the mixture of alkyl ammonium and phosphonium salts favored the production of PET nanocomposites with intercalated and partially exfoliated morphologies with slight improvement in thermal stability. In addition, the incorporation of these organoclays tended to inhibit PET crystallization behavior, which is profitable in the production of transparent bottles.

scholarly journals Observation and Characterization of Fragile Organometallic Molecules Encapsulated in Single-Wall Carbon Nanotubes

2014 ◽  
Vol 2014 ◽  
pp. 1-5
Author(s):  
Daisuke Ogawa ◽  
Ryo Kitaura ◽  
Takeshi Saito ◽  
Shinobu Aoyagi ◽  
Eiji Nishibori ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
High Yield ◽  
Single Wall Carbon Nanotubes ◽  
X Ray Diffraction ◽  
Single Wall Carbon ◽  
X Ray ◽  
Transmission Electron ◽  
Organometallic Molecules ◽  
X Ray Absorption

Thermally fragile tris(η5-cyclopentadienyl)erbium (ErCp3) molecules are encapsulated in single-wall carbon nanotubes (SWCNTs) with high yield. We realized the encapsulation of ErCp3with high filling ratio by using high quality SWCNTs at an optimized temperature under higher vacuum. Structure determination based on high-resolution transmission electron microscope observations together with the image simulations reveals the presence of almost free rotation of each ErCp3molecule in SWCNTs. The encapsulation is also confirmed by X-ray diffraction. Trivalent character of Er ions (i.e., Er3+) is confirmed by X-ray absorption spectrum.

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