Char Studies: Flame Retarded Polycarbonate/PET Blend

1994 ◽  
Vol 12 (6) ◽  
pp. 551-581 ◽  
Author(s):  
Joseph Green
Keyword(s):  
Porous Structure ◽  
Flame Retardant ◽  
Cone Calorimeter ◽  
Oxygen Index ◽  
The Other ◽  
High Oxygen Concentration ◽  
Dsc Studies ◽  
Flame Retarded ◽  
Creep Modulus ◽  
Tga And Dsc

Bromine and phosphorus were shown to be synergistic in flame retarding a polycarbonate/PET blend as measured by oxygen index. This synergy is enhanced when both elements are present in the same molecule. Cone calorimeter data confirm these observations. Chars were formed by py rolysis in the TGA apparatus, by burning at high oxygen concentration in the oxygen index apparatus and by forced combustion in the cone calorimeter. Chars formed from the polymer blend containing the brominated phosphate gave 40-50% more char by weight than when bromine, phosphorus or blends of the two were used. Analyses of the chars showed no bromine and considerable phosphorus. TGA and DSC studies suggest that the polycarbonate and the PET undergo transesterification during pyrolysis above 400°C and the brominated phosphate acts as a transesterification inhibitor or stabilizer. SEM of the chars showed a considerable difference. When the brominated phosphate was used the char had a fine porous structure and thick solid skin. The other chars showed poorer structure and less to no skin. Measurement of the properties of the chars showed the char from the polymer containing the brominated phosphate to have a creep modulus 35 times greater than the char obtained from the polymer containing the bromine flame retardant.

Effect of Zinc and Zinc Borate on Fire Properties of Modified Polyphenylene Oxide

1993 ◽  
Vol 11 (3) ◽  
pp. 210-231 ◽  
Author(s):  
R. Benrashid ◽  
G.L. Nelson ◽  
Donald J. Ferm
Keyword(s):  
Vapor Phase ◽  
Marked Reduction ◽  
Oxygen Index ◽  
The Other ◽  
Zinc Borate ◽  
Polyphenylene Oxide ◽  
Flame Retarded ◽  
Smoke Chamber ◽  
Fire Properties ◽  
Phase Activity

Modified polyphenylene oxide resin (m-PPO) (virgin) and m-PPO flame retarded with triaryl phosphate (FR m-PPO) were blended with zinc borate, zinc, and zinc/zinc borate. Both virgin and FR m-PPO containing zinc borate showed a marked reduction in smoke production (flaming and non- flaming-NBS Smoke Chamber). In FR m-PPO a reduction in oxygen index values was seen for zinc borate, except at the highest level tested (50 PHR). Zinc, on the other hand, showed an increase in oxygen index for FR m-PPO. Given the potential for both condensed and vapor phase activity for triaryl phosphate in m-PPO, the reduction in both smoke and oxygen index by zinc borate suggests a deactivation of the vapor phase activity of triaryl phosphate.

Synergistic Effect between Montmorillonite Intercalated by Melamine and Intumescent Flame Retardant (IFR) on Polypropylene

2011 ◽  
Vol 295-297 ◽  
pp. 315-318
Author(s):  
Hong Fang Zhu ◽  
Juan Li ◽  
Liang Xu ◽  
Kang Tao ◽  
Li Xin Xue ◽  
...  
Keyword(s):  
Synergistic Effect ◽  
Flame Retardant ◽  
Cone Calorimeter ◽  
Oxygen Index ◽  
Intumescent Flame Retardant ◽  
Limited Oxygen Index ◽  
Cation Exchange Reaction ◽  
Melamine Salt ◽  
Better Than ◽  
Limited Oxygen

This Montmorillonite modified by melamine (MA-MMT) was prepared via cation exchange reaction by using melamine salt as intercalation reagent. MA-MMT and Na-MMT was combined with intumescent flame retardant (IFR) to be adopted into polypropylene (PP), respectively. The synergistic effect between MA-MMT and IFR and the influence of melamine in MMT layers on fire-resistant performance was evaluated. Results of limited oxygen index (LOI) tests and UL-94 tests indicate that melamine salts in MMT layers behaved better than Na-MMT in PP/IFR system. According to the results of cone calorimeter tests and scanning electron microscope (SEM), it concludes that melamine salts act as gas agent to provide migration impetus and expanded power, which caused a well-structured and strong char that had better ability to endure heat erosion. A good synergistic effect between MA-MMT and IFR is constructed.

The effects of N,N-(pyromellitoyl)-bis-l-phenylalanine diacid ester glycol on the flame retardancy and physical–mechanical properties of rigid polyurethane foams

2018 ◽  
Vol 36 (6) ◽  
pp. 535-545 ◽  
Author(s):  
Daikun Jia ◽  
Yi Tong ◽  
Jin Hu
Keyword(s):  
Flame Retardant ◽  
Polyurethane Foam ◽  
Flame Retardancy ◽  
Cone Calorimeter ◽  
Oxygen Index ◽  
Polyurethane Foams ◽  
Initial Decomposition Temperature ◽  
Limiting Oxygen Index ◽  
Rigid Polyurethane Foams ◽  
Upper Limit

Flame-retardant rigid polyurethane foams incorporating N,N-(pyromellitoyl)-bis-l-phenylalanine diacid ester glycol have been prepared. After adding N,N-(pyromellitoyl)-bis-l-phenylalanine diacid ester glycol, the density and compressive strength of the polyurethane foams were seen to decrease. The flame retardancy of the polyurethane foams has been characterized by limiting oxygen index, upper limit–94, and cone calorimeter tests. The polyurethane foam with 2.27 wt% N,N-(pyromellitoyl)-bis-l-phenylalanine diacid ester glycol gave a highest limiting oxygen index of 33.4%, and the peak heat release rate of polyurethane foam reduced to 19.5 kW/m2 from 47.6 kW/m2 of PU-0 without N,N-(pyromellitoyl)-bis-l-phenylalanine diacid ester glycol. Upper limit–94 revealed N,N-(pyromellitoyl)-bis-l-phenylalanine diacid ester glycol did not change the burning rating, and all polyurethane foams had passed V-0 rating. The thermal stability of polyurethane foams has been investigated by thermogravimetric analyzer. N,N-(pyromellitoyl)-bis-l-phenylalanine diacid ester glycol significantly increased the initial decomposition temperature of polyurethane foams and their residues. In addition, the morphology of residual char from the flame-retarded polyurethane foams after cone calorimeter tests has also been characterized by digital photographs. The results indicated that N,N-(pyromellitoyl)-bis-l-phenylalanine diacid ester glycol significantly enhanced the strength and compatibility of the char layer formed by the polyurethane foams. These results indicate that N,N-(pyromellitoyl)-bis-l-phenylalanine diacid ester glycol can improve both the quality and quantity of the char, which has a significant effect on the flame-retardant properties of the foam.

Interaction of Flame-Retardant and Untreated Cotton Fabrics during Burning

1977 ◽  
Vol 47 (5) ◽  
pp. 351-360 ◽  
Author(s):  
Stanley R. Hobart ◽  
Charles H. Mack
Keyword(s):  
Flame Retardant ◽  
Cotton Fabric ◽  
Flame Retardancy ◽  
Oxygen Index ◽  
Cotton Fabrics ◽  
Transfer Effect ◽  
Geometrical Configuration ◽  
Untreated Cotton ◽  
Phosphorus Containing ◽  
Flame Retarded

Transfer of flame retardancy from fabric treated with THPOH-NH3 to untreated cotton fabric during burning was observed on fabric samples sewed together with glass thread. The transfer effect was evidenced by the development of substantial char and the presence of phosphorus and nitrogen in the char of the untreated fabric. Oxygen-index determinations on multilayered combinations of flame-retarded (FR) and untreated fabrics also supported this observation. The extent of FR transfer varied with the geometrical configuration of the layers and the FR add-on. Tests showed that smoke from combustion of THPOH-NH3-treated fabric, passed through untreated cotton fabric, was the means of transfer of phosphorus, nitrogen, and flame retardancy. The FR transfer effect was also demonstrated for several other phosphorus-containing flame-retardancy treatments.

Synthesis of a boron/nitrogen-containing compound based on triazine and boronic acid and its flame retardant effect on epoxy resin

2016 ◽  
Vol 29 (5) ◽  
pp. 513-523 ◽  
Author(s):  
Tie Zhang ◽  
Weishi Liu ◽  
Meixiao Wang ◽  
Ping Liu ◽  
Yonghong Pan ◽  
...  
Keyword(s):  
Flame Retardant ◽  
Epoxy Resin ◽  
Boronic Acid ◽  
Cone Calorimeter ◽  
Oxygen Index ◽  
Triazine Ring ◽  
Limiting Oxygen Index ◽  
Ul 94 ◽  
Flame Retardant Properties ◽  
Boron Nitrogen

With the aim of developing a novel organic flame retardant, an organic boronic acid derivative containing a triazine ring (2,4,6-tris(4-boronic-2-thiophene)-1,3,5-triazine (3TT-3BA)) was synthesized. The thermal properties of 3TT-3BA and its corresponding intermediate products were investigated by thermogravimetric analysis. The results show that 3TT-3BA has a high char yield (56.9%). The flame retardant properties of epoxy resin (EP) with 3TT-3BA were investigated by cone calorimeter, limiting oxygen index (LOI) test, and vertical burning test (UL 94). The LOI of EP with 20% 3TT-3BA is 31.2% and the UL 94 V-0 rating is achieved for EP with 20% 3TT-3BA. The flame retardant mechanism of 3TT-3BA in EP was investigated using TGA–Fourier transform infrared spectroscopy and scanning electron microscopy.

scholarly journals Expandable Graphite for Flame Retardant PA6 Applications

Polymers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2733
Author(s):  
Florian Tomiak ◽  
Klaus Rathberger ◽  
Angelina Schöffel ◽  
Dietmar Drummer
Keyword(s):  
Flame Retardant ◽  
Cone Calorimeter ◽  
Oxygen Index ◽  
Fire Behavior ◽  
Polyamide 6 ◽  
Heat Fluxes ◽  
Expandable Graphite ◽  
Fire Tests ◽  
Inhibiting Effect ◽  
Ul 94

A new expandable graphite (EG) type was studied as a flame retardant additive in Polyamide 6 (PA6). The fire behavior was characterized by a cone calorimeter using external heat fluxes of 35, 50 and 65 kW/m2, limiting the oxygen index (LOI) and UL-94 burning tests. Additionally, electric and thermal conductivity as well as rheological properties were characterized to provide a general property overview. Fire tests were conducted using dry and humid conditioned samples. Cone Calorimeter tests showed a minimum filling degree of 15 wt.% (8.6 vol.%) EG was required to achieve a significant fire inhibiting effect in PA6 independent of the sample condition. UL-94 fire tests show a V0 classification at filling degrees greater than 20 wt.% (humid) and 25 wt.% (dry), although the associated LOI values of 39% and 38% demonstrate good flammability inhibition. Correlation analyses were conducted to identify major influences given by the sample condition for most important key figures measured in cone calorimeter tests. Accordingly, humid-conditioned samples containing between 2.5 (PA6 + 25 wt.% EG) and 4.2 wt.% (PA6) water were found to reduce the total heat evolved (THE) on average by 16% and the total smoke production (TSP) on average by 22%.

Smoke Suppressant and Flame Retardant Properties of PVC/Zinc Hydroxystannate Composites

2012 ◽  
Vol 512-515 ◽  
pp. 2804-2807 ◽  
Author(s):  
Ling Yang ◽  
Yong Yi Wang
Keyword(s):  
Flame Retardant ◽  
Cone Calorimeter ◽  
Oxygen Index ◽  
Limiting Oxygen Index ◽  
Smoke Suppressant ◽  
Poly Vinyl Chloride ◽  
Smoke Density ◽  
Hazardous Gases ◽  
Zinc Hydroxystannate ◽  
Flame Retardant Properties

The effects of zinc hydroxystannte on the flame-retardant and smoke-suppressant properties of poly (vinyl chloride) (PVC) as well as their mechanism for flame retardancy and smoke suppression were studied through the limiting oxygen index (LOI) test, UL94 test, smoke density test, cone calorimeter, and ESEM. The results show that incorporation of a small amount of ZHS can greatly increase the LOI of PVC and reduce the smoke density of PVC during combustion. The cone data and ESEM analyses results show that incorporation of a small amount of ZHS greatly promotes the char formation of PVC and decreases the amount of hazardous gases released in PVC during combustion.

scholarly journals The Preparation, Thermal Properties, and Fire Property of a Phosphorus-Containing Flame-Retardant Styrene Copolymer

Materials ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 127 ◽  
Author(s):  
Yu Sun ◽  
Yazhen Wang ◽  
Li Liu ◽  
Tianyuan Xiao
Keyword(s):  
Thermal Properties ◽  
Thermogravimetric Analysis ◽  
Flame Retardant ◽  
Oxygen Index ◽  
Limiting Oxygen Index ◽  
Chemical Structures ◽  
1H Nuclear Magnetic Resonance ◽  
Phosphorus Containing ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

A 9,10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide (DOPO) acrylate, (6-oxidodibenzo [c,e][1,2] oxaphosphinin-6-yl) methyl acrylate (DOPOAA), has been prepared. Copolymers of styrene (St) and DOPOAA were prepared by emulsion polymerization. The chemical structures of copolymers containing levels of DOPOAA were verified using Fourier transform infrared (FT-IR) spectroscopy and 1H nuclear magnetic resonance (1H-NMR) spectroscopy. The thermal properties and flame-retardant behaviors of DOPO-containing monomers and copolymers were observed using thermogravimetric analysis and micro calorimetry tests. From thermogravimetric analysis (TGA), it was found out that the T5% for decomposition of the copolymer was lower than that of polystyrene (PS), but the residue at 700 °C was higher than that of PS. The results from micro calorimetry (MCC) tests indicated that the rate for the heat release of the copolymer combustion was lower than that for PS. The limiting oxygen index (LOI) for combustion of the copolymer rose with increasing levels of DOPOAA. These data indicate that copolymerization of the phosphorus-containing flame-retardant monomer, DOPOAA, into a PS segment can effectively improve the thermal stability and flame retardancy of the copolymer.

scholarly journals An Effective Method for Preparation of Liquid Phosphoric Anhydride and Its Application in Flame Retardant Epoxy Resin

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2205
Author(s):  
Qian Li ◽  
Yujie Li ◽  
Yifan Chen ◽  
Qiang Wu ◽  
Siqun Wang
Keyword(s):  
Flame Retardant ◽  
Epoxy Resin ◽  
Epoxy Resins ◽  
Oxygen Index ◽  
Decomposition Temperature ◽  
Ease Of Use ◽  
Limiting Oxygen Index ◽  
Good Thermal Stability ◽  
Low Viscosity ◽  
The Impact

A novel liquid phosphorous-containing flame retardant anhydride (LPFA) with low viscosity was synthesized from 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and methyl tetrahydrophthalic anhydride (MeTHPA) and further cured with bisphenol-A epoxy resin E-51 for the preparation of the flame retardant epoxy resins. Both Fourier transform infrared spectroscopy (FT-IR), mass spectrometry (MS) and nuclear magnetic resonance (NMR) measurements revealed the successful incorporation of DOPO on the molecular chains of MeTHPA through chemical reaction. The oxygen index analysis showed that the LPFA-cured epoxy resin exhibited excellent flame retardant performance, and the corresponding limiting oxygen index (LOI) value could reach 31.2%. The UL-94V-0 rating was achieved for the flame retardant epoxy resin with the phosphorus content of 2.7%. With the addition of LPFA, the impact strength of the cured epoxy resins remained almost unchanged, but the flexural strength gradually increased. Meanwhile, all the epoxy resins showed good thermal stability. The glass transition temperature (Tg) and thermal decomposition temperature (Td) of epoxy resin cured by LPFA decreased slightly compared with that of MeTHPA-cured epoxy resin. Based on such excellent flame retardancy, low viscosity at room temperature and ease of use, LPFA showed potential as an appropriate curing agent in the field of electrical insulation materials.

Research on Properties of Flame Retardant Silk Georgette

2012 ◽  
Vol 441 ◽  
pp. 284-288
Author(s):  
Hong Lu ◽  
Yan Chen ◽  
Jin Ping Guan
Keyword(s):  
Flame Retardant ◽  
Graft Copolymerization ◽  
Oxygen Index ◽  
Color Fastness ◽  
Limiting Oxygen Index ◽  
Wrinkle Resistance ◽  
Garment Design

In this paper, four kinds of silk georgettes with different density were chosen as samples. The flame retardant formaldehyde-free vinyl phosphate dimethyl-2-(methacryloyloxyethyl) phosphate (DMMEP) was grafted onto them by graft copolymerization technique. Some tests such as Limiting Oxygen Index (LOI), vertical flammability, wrinkle resistance and color fastness were examined. Through the discussion and analysis of the experiment results, the properties of original and treated fabrics were compared and suggestions were given for the flame retardant process and garment design.

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