Estimation of heat release rate for polymer–filler composites by cone calorimetry

The fire performance of polycarbonate resin and the role of glass fibre reinforcement in altering the fire performance was investigated. Three different fibre weaves with comparable surface density, plain, twill, and unidirectional glass fabrics, were used as reinforcements. E-glass fabrics were solution-impregnated with polycarbonate/dichloromethyl, laid up, and compression-moulded to consolidate the glass fibre reinforced polycarbonate composite. Cone calorimetry tests with an incident radiant flux of 35 kW/m2 were used to investigate the fire properties of polycarbonate resin and its composites. Results showed that glass fibre reinforcement improves polycarbonate performance by delaying its ignition, decreasing its heat release rate, and lowering the mass loss rate. The three fibre weave types exhibited similar time to ignition. However, unidirectional fibre had a 35% lower peak heat release rate followed when compared to plain and twill weave fibres.

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Fire Performance of Nylon Nanocomposites Fabricated by Melt Intercalation

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.334-335.737 ◽

2007 ◽

Vol 334-335 ◽

pp. 737-740

Author(s):

Russel J. Varley ◽

Andrew M. Groth ◽

Kok Hoong Leong

Keyword(s):

Heat Release ◽

Heat Release Rate ◽

Release Rate ◽

Fire Performance ◽

Fire Retardancy ◽

Cone Calorimetry ◽

Char Layer ◽

Transmission Electron ◽

Peak Heat Release Rate ◽

In Fire

This paper presents results of a study carried out to evaluate the effects of an organomodified nanoclay, either on its own or in combination with a polyimide, upon the fire performance of a commercially available nylon. The fire performance, as determined using cone calorimetry showed that up to 40% improvement in the peak heat release rate could be achieved at addition levels of only around 5wt% of nanoclay. The level of improvement was shown to be strongly dependent upon nanoscale dispersion with a more highly exfoliated morphology, as determined using transmission electron microscopy, which showed a greater reduction in the peak heat release rate compared to a more ordered intercalated structure. Investigation of the mechanism of fire retardancy showed that the reduction in the heat release rate is due to the nanoclay reinforcing the char layer which prevented combustible products from entering in to the gaseous phase. Generally, though, the time to ignition is unaffected by nanoclay additions. The addition of the polyimide to the nanoclay reinforced nylon was inconclusive showing little evidence of further improvements in fire performance.

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Cone calorimeter evaluation of reinforced hybrid wood–aluminum composites

Journal of Fire Sciences ◽

10.1177/0734904116683717 ◽

2016 ◽

Vol 35 (2) ◽

pp. 118-131

Author(s):

Junfeng Hou ◽

Zhiyong Cai ◽

Keyang Lu

Keyword(s):

Aluminum Alloy ◽

Heat Release ◽

Heat Release Rate ◽

Release Rate ◽

Mass Loss Rate ◽

Alloy Sheet ◽

Aluminum Alloy Sheet ◽

Aluminum Composites ◽

Cone Calorimetry ◽

Combustion Performance

Combustion performance for three types of wood–aluminum composites was investigated using cone calorimetry tests. The results revealed that time to ignition of the specimens was increased and more than 100 times after the lamination of 1.6-mm-thick aluminum alloy sheet on the surface (from 17 to 1990 s). And residual mass of the wood–aluminum composites was improved and almost quadrupled (from 21.795% to 81.664%). The peak heat release rate, average heat release rate, total heat release, and mean mass loss rate of wood–aluminum composites with 1.6-mm-thick aluminum alloy sheet on the surface were decreased to 70.18%, 48.71%, 24.27%, and 80.60%, respectively. However, yields of both CO and CO2 are slightly improved with the increase in the thickness of aluminum alloy sheet because of incomplete combustion. The application of aluminum alloy sheets to the wood-based composites is an effective method for improving the combustion performance.

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Effect of Heat of Reaction and Charring Properties on Heat Release Rate during Combustion

Fire Science and Engineering ◽

10.7731/kifse.52446b30 ◽

2021 ◽

Vol 35 (6) ◽

pp. 1-7

Author(s):

Myung-Kyu Lee ◽

Seul-Hyun Park

Keyword(s):

Heat Release ◽

Heat Release Rate ◽

Release Rate ◽

Computational Analysis ◽

Heat Of Reaction ◽

Cone Calorimetry ◽

Reaction Heat ◽

Thermal Pyrolysis ◽

Effective Heat Of Combustion ◽

The Relationship

The heat release rate (HRR) of fires can be determined from the relationship between the thermal pyrolysis rate of combustibles and the effective heat of combustion. To accurately determine the thermal pyrolysis rate of combustibles, it is important to understand the heat of reaction of combustibles. However, this parameter is difficult to measure for combustibles, such as wood, that produce charring during combustion because they undergo a multi-step pyrolysis reaction. In this study, the ISO 5660-1 standard method was used to perform cone calorimetry experiments to understand how the HRR is affected by the heat of reaction heat and charring properties of combustibles. To this end, the HRR calculated using FDS computational analysis was compared to the measured value from the ISO 5660-1 cone calorimetry experiments. A dehydrated Douglas-fir, an evergreen tree of the pine family, was used as a combustible material. The cone calorimetry experiment and FDS computational analysis results confirmed that increases in the heat of reaction and charring properties were directly correlated with the decrease in the HRR.

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Effect of modified hydrotalcites on flame retardancy and physical properties of paper

BioResources ◽

10.15376/biores.14.2.3991-4005 ◽

2019 ◽

Vol 14 (2) ◽

pp. 3991-4005

Author(s):

Songlin Wang ◽

Xuxu Yang ◽

Fei Wang ◽

Zongjia Song ◽

Hehe Dong ◽

...

Keyword(s):

Heat Release ◽

Heat Release Rate ◽

Release Rate ◽

Coupling Agent ◽

Microscopic Analysis ◽

Particle Size Analysis ◽

Size Analysis ◽

Cone Calorimetry ◽

Electron Microscopic ◽

Limiting Oxygen Index

Functionalized layered double hydroxides (LDHs) based on a multi-modifier system composed of itaconic acid (ITA) and titanate coupling agent (NDZ-201) were designed and fabricated in this paper with the aim to develop high-performance fire retardant paper. The structure of LDHs were characterized using Fourier transform infrared spectroscopic analysis, X-ray diffraction analysis, thermogravimetric analysis (TGA), scanning electron microscopic analysis, cone calorimetry, and laser particle size analysis. The results showed that carbonate anions were partially replaced by ITA, whereas the titanate coupling agent was attached to the surfaces of the hydrotalcites. The limiting oxygen index (LOI), TGA curves, total heat release rate (THR), and heat release rate (HRR) indicated that as the addition of hydrotalcites increased, the modified LDHs’ LOI value and thermal stability noticeably increased compared to the unmodified hydrotalcites, and the HRR and THR of the material decreased. When the addition amount was 25%, the LOI of ITA-LDHs was 26.9%. However, the Mg-Al hydrotalcites adversely affected the strength index of flame-retardant paper; the modified hydrotalcites clearly reduced this effect, and the whiteness of paper increased and reached 83%.

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Polyisocyanurate Foam Pyrolysis and Flame Spread Modeling

Applied Sciences ◽

10.3390/app11083463 ◽

2021 ◽

Vol 11 (8) ◽

pp. 3463

Author(s):

Dushyant M. Chaudhari ◽

Stanislav I. Stoliarov ◽

Mark W. Beach ◽

Kali A. Suryadevara

Keyword(s):

Heat Release ◽

Heat Release Rate ◽

Flame Spread ◽

Release Rate ◽

Full Scale ◽

Insulation Material ◽

Cone Calorimetry ◽

Scanning Calorimetry ◽

Microscale Combustion Calorimetry ◽

Full Scale Tests

Polyisocyanurate (PIR) foam is a robust thermal insulation material utilized widely in the modern construction. In this work, the flammability of one representative example of this material was studied systematically using experiments and modeling. The thermal decomposition of this material was analyzed through thermogravimetric analysis, differential scanning calorimetry, and microscale combustion calorimetry. The thermal transport properties of the pyrolyzing foam were evaluated using Controlled Atmosphere Pyrolysis Apparatus II experiments. Cone calorimetry tests were also carried out on the foam samples to quantify the contribution of the blowing agent (contained within the foam) to its flammability, which was found to be significant. A complete pyrolysis property set was developed and was shown to accurately predict the results of all aforementioned measurements. The foam was also subjected to full-scale flame spread tests, similar to the Single Burning Item test. A previously developed modeling approach based on a coupling between detailed pyrolysis simulations and a spatially-resolved relationship between the total heat release rate and heat feedback from the flame, derived from the experiments on a different material in the same experimental setup, was found to successfully predict the evolution of the heat release rate measured in the full-scale tests on the PIR foam.

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