Oxygen index and minimum limiting rates of polymer combustion

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.

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Effects of Various Types of Expandable Graphite and Blackcurrant Pomace on the Properties of Viscoelastic Polyurethane Foams

Materials ◽

10.3390/ma14071801 ◽

2021 ◽

Vol 14 (7) ◽

pp. 1801

Author(s):

Rafał Oliwa ◽

Joanna Ryszkowska ◽

Mariusz Oleksy ◽

Monika Auguścik-Królikowska ◽

Małgorzata Gzik ◽

...

Keyword(s):

Mechanical Properties ◽

Chemical Structure ◽

Oxygen Index ◽

Polyurethane Foams ◽

Expandable Graphite ◽

Ftir Analysis ◽

Limiting Oxygen Index ◽

Peak Heat Release Rate ◽

Physical And Chemical ◽

Scanning Electron

We investigated the effect of the type and amount of expandable graphite (EG) and blackcurrant pomace (BCP) on the flammability, thermal stability, mechanical properties, physical, and chemical structure of viscoelastic polyurethane foams (VEF). For this purpose, the polyurethane foams containing EG, BCP, and EG with BCP were obtained. The content of EG varied in the range of 3–15 per hundred polyols (php), while the BCP content was 30 php. Based on the obtained results, it was found that the additional introduction of BCPs into EG-containing composites allows for an additive effect in improving the functional properties of viscoelastic polyurethane foams. As a result, the composite containing 30 php of BCP and 15 php of EG with the largest particle size and expanded volume shows the largest change in the studied parameters (hardness (H) = 2.65 kPa (+16.2%), limiting oxygen index (LOI) = 26% (+44.4%), and peak heat release rate (pHRR) = 15.5 kW/m2 (−87.4%)). In addition, this composite was characterized by the highest char yield (m600 = 17.9% (+44.1%)). In turn, the change in mechanical properties is related to a change in the physical and chemical structure of the foams as indicated by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) analysis.

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

Materials ◽

10.3390/ma14092205 ◽

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.

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Research on Properties of Flame Retardant Silk Georgette

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.441.284 ◽

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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Effect of Zinc, Zinc Oxide and Zinc Borate on the Flammability of Polycarbonate

Journal of Fire Sciences ◽

10.1177/073490419501300305 ◽

1995 ◽

Vol 13 (3) ◽

pp. 224-234 ◽

Cited By ~ 2

Author(s):

Ramazan Benrashid ◽

Gordon L. Nelson ◽

Donald J. Ferm ◽

Leland W. Chew

Keyword(s):

Zinc Oxide ◽

Heat Release ◽

Oxygen Index ◽

Ohio State University ◽

Zinc Borate ◽

State University ◽

Dsc Studies ◽

Release Studies ◽

Chamber Studies ◽

Smoke Chamber

Polycarbonate was blended with zinc, zinc borate (2ZnO·3B2O 3·3.5H2O) and zinc oxide. Blends made of zinc/polycarbonate and especially zinc borate/polycarbonate show major improvement in oxygen index values. Ohio State University (OSU) heat release studies show reduction in heat release only for zinc borate/polycarbonate blends compared to virgin polycarbonate. No improvement in smoke suppression was observed from NBS Smoke Chamber studies for these blends. From DSC studies there was a low ering of Tg's. Thermogravimetric analyses show the blends have lower tempera ture stability in nitrogen (50% weight loss) compared to a control.

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Effects of collagen fiber addition on the combustion and thermal stability of natural rubber

Journal of Leather Science and Engineering ◽

10.1186/s42825-020-00040-1 ◽

2020 ◽

Vol 2 (1) ◽

Author(s):

Weixing Xu ◽

Xintao Wu ◽

Qilin Wen ◽

Shuangyang Li ◽

Yongjiao Song ◽

...

Keyword(s):

Natural Rubber ◽

Flame Retardant ◽

Nitrogen Content ◽

Flame Retardancy ◽

Collagen Fiber ◽

Oxygen Index ◽

Air Pockets ◽

Thermal Stability Of ◽

Limited Oxygen ◽

Properties Of Composites

Abstract Collagen fiber (CF) and silane coupling agent-modified collagen fiber (MCF) were used as flame retardant filler for natural rubber (NR) modification. The combustion phenomena and properties of composites blended with different dosages of CF or MCF were compared to elucidate the flame retardant mechanism of the composites. The flame retardancy of NR can be enhanced effectively by increasing nitrogen content (the nitrogen content of CF is about 18%), creating air pockets, and structuring the flame retardant network in the composites. MCF failed to structure a flame retardant network in the composite, indicating that its modification effects of MCF are weaker than those of CF. When CF dosage was 30 wt%, the composite can achieve the best flame retardancy, with limited oxygen index of 29.4% and without smoke and dripping during burning. This study demonstrated a new method for the flame retardant modification of NR. Graphical abstract

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Flammability Test for Granular Synthetic Resins by the Modified Oxygen Index Method

Journal of Fire Sciences ◽

10.1177/073490419701500204 ◽

1997 ◽

Vol 15 (2) ◽

pp. 126-143

Author(s):

Yusaku Iwata ◽

Eiji Yanai

Keyword(s):

Thermal Properties ◽

Oxygen Index ◽

Index Method ◽

Flammability Test ◽

Synthetic Resins

A new oxygen index method is developed for testing the flamma bility of the granular synthetic resins. The oxygen index values of several granular resins are able to be determined by this method. The oxygen index values obtained by this method are compared with those obtained by the con ventional method. The granular samples used here are mainly classified into three groups, according to their thermal properties.

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Flame Retardation of Plain Weave Fabrics Made of Polyacrylonitrile Pre-Oxidized Yarns

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.175-176.465 ◽

2011 ◽

Vol 175-176 ◽

pp. 465-468 ◽

Cited By ~ 3

Author(s):

Lei Shi ◽

Hua Wu Liu ◽

Ping Xu ◽

Dang Feng Zhao

Keyword(s):

Mechanical Properties ◽

Flame Retardant ◽

Oxygen Index ◽

Limiting Oxygen Index ◽

Plain Weave ◽

Weave Fabric ◽

Short Period ◽

Flame Retardation ◽

Fabric Structures

Plain weave fabrics of polyacrylonitrile pre-oxidation yarns (PANOF) were prepared by small rapier loom. The flame retardation properties, mechanical properties and wear behaviors of PANOF plain weave fabrics were tested. The limiting oxygen index (LOI) of these PANOF plain weave fabric samples was 31%, which meets the criterion of flame-retardant fabrics. These fabrics neither melt nor shrunk when left in flame for a short period of time and the fabric structures were well maintained. Compared with flammable polyacrylonitrile fabrics, the polyacrylonitrile pre-oxidation fabrics exhibited excellent flame retardation properties, with satisfactory mechanical properties and comfortable handle.

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