Fire behavior of halogen-free flame retardant electrical cables with the cone calorimeter

This work aims at developing polyamide 1010 (PA1010) composites with improved fire behavior using a halogen-free flame-retardant system based on melamine (Me) and gallic acid (GA) complexes (MA). The MA complexes were formed by hydrogen bonding, starting from 1:2, 1:1, 2:1 Me:GA molar ratios. PA1010 composites were obtained by melt mixing, followed by compression molding. MA provided a plasticizing effect on the PA1010 matrix by decreasing the glass transition temperature. The influence of MA on PA1010 chain packaging was highlighted in the X-ray diffraction patterns, mainly in the amorphous phase, but affected also the α and γ planes. This was reflected in the dynamic mechanical properties by the reduction of the storage modulus. H-bonds occurrence in MA complexes, improved the efficiency in the gaseous form during fire exposure, facilitating the gas formation and finally reflected in thermal stability, thermo-oxidative stability, LOI results, and vertical burning behavior results. PA1010 containing a higher amount of GA in the complex (MA12) displayed a limiting oxygen index (LOI) value of 33.6%, much higher when compared to neat PA1010 (25.8%). Vertical burning tests showed that all the composites can achieve the V-0 rating in contrast with neat PA1010 that has V-2 classification.

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Study on thermal degradation and flame retardant property of halogen-free polypropylene composites using XPS and cone calorimeter

Journal of Applied Polymer Science ◽

10.1002/app.37700 ◽

2012 ◽

Vol 127 (2) ◽

pp. 1084-1091 ◽

Cited By ~ 11

Author(s):

Kuang-Chung Tsai ◽

Chen-Feng Kuan ◽

Chia-Hsun Chen ◽

Hsu-Chiang Kuan ◽

Shu-Wei Hsu ◽

...

Keyword(s):

Thermal Degradation ◽

Flame Retardant ◽

Cone Calorimeter ◽

Polypropylene Composites ◽

Flame Retardant Property ◽

Halogen Free

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Expandable Graphite for Flame Retardant PA6 Applications

Polymers ◽

10.3390/polym13162733 ◽

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%.

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

Flame Retardancy and Thermal Stability of Materials ◽

10.1515/flret-2019-0002 ◽

2019 ◽

Vol 2 (1) ◽

pp. 9-18 ◽

Cited By ~ 1

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.

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Analysis of the Fire Behavior of Polymers (PP, PA 6 and PE-LD) and Their Improvement Using Various Flame Retardants

Materials ◽

10.3390/ma13245756 ◽

2020 ◽

Vol 13 (24) ◽

pp. 5756

Author(s):

Dieter Hohenwarter ◽

Hannelore Mattausch ◽

Christopher Fischer ◽

Matthias Berger ◽

Bernd Haar

Keyword(s):

Heat Release ◽

Flame Retardant ◽

Heat Release Rate ◽

Release Rate ◽

Radiation Intensity ◽

Cone Calorimeter ◽

Flame Retardants ◽

Fire Behavior ◽

Expandable Graphite ◽

Aging Effects

The fire behavior of polymers is examined primarily with the time-dependent heat release rate (HRR) measured with a cone calorimeter. The HRR is used to examine the fire behavior of materials with and without flame retardants, especially Polypropylene (PP-Copo) and Polyethylene (PE-LD). Polypropylene is stored for up to 99 days under normal conditions and the heat release rate shows especially changes about 100 s after irradiation with cone calorimeter, which may be caused by aging effects. The effect of crosslinking to the burning behavior of PP was examined too. Polyamides (PA 6) are irradiated with a radiation intensity of 25 kW/m2 to 95 kW/m2 and fire-related principles between radiation intensity and time to ignition can be derived from the measurement results. In order to comprehensively investigate the fire behavior of PP (also with flame retardant additives), the samples were also exposed to a flame, according to UL 94 with small power (50 W) and is inflamed with the power of a few 100 W. The irradiation causes different trigger mechanisms for the flame retardant additives in a plastic than the flame exposure. It is shown that the compound, which is favorable for irradiation, is not necessarily good for flame exposure. It can be seen that expandable graphite alone or with the addition of other additives is a very effective flame retardant for PP.

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Fire behavior of flame-retardant polyurethane semi-rigid foam in presence of nickel (II) oxide and graphene nanoplatelets additives

Journal of Polymer Research ◽

10.1007/s10965-021-02450-z ◽

2021 ◽

Vol 28 (3) ◽

Author(s):

Halima Saadiya Ababsa ◽

Zitouni Safidine ◽

Ahmed Mekki ◽

Yves Grohens ◽

Amina Ouadah ◽

...

Keyword(s):

Flame Retardant ◽

Fire Behavior ◽

Graphene Nanoplatelets ◽

Rigid Foam

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Flame Retardant Epoxy Resins Containing Microcapsules

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.197-198.1346 ◽

2011 ◽

Vol 197-198 ◽

pp. 1346-1349 ◽

Cited By ~ 4

Author(s):

Fa Chao Wu

Keyword(s):

Flame Retardant ◽

Cone Calorimeter ◽

Epoxy Resins ◽

Flame Retardants ◽

Melamine Resin ◽

Element Analysis ◽

Ul 94

Bis(2,6,7-trioxa-l-phosphabicyclo[2.2.2]octane-4-methanol) melaminium salt (Melabis) and microcapsules of Melabis with melamine resin shell as flame retardants (FR), respectively, were synthesized. Their structures were characterized by NMR, IR, SEM, TG and element analysis. 20% weight of microcapsules was doped into epoxy resins (EP) to get 28.5 % of LOI and UL 94 V-0. The heat and smoke release of EP containing microcapsules was valued by cone calorimeter.

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An efficient halogen-free flame retardant for polyethylene: piperazinemodified ammonium polyphosphates with different structures

Chinese Journal of Polymer Science ◽

10.1007/s10118-016-1855-8 ◽

2016 ◽

Vol 34 (11) ◽

pp. 1339-1353 ◽

Cited By ~ 27

Author(s):

Shi-fu Liao ◽

Cong Deng ◽

Sheng-chao Huang ◽

Jing-yu Cao ◽

Yu-zhong Wang

Keyword(s):

Flame Retardant ◽

Halogen Free

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