Pyrolysis-Combustion Flow Calorimetry: A Powerful Tool To Evaluate the Flame Retardancy of Polymers

Author(s):  
R. Sonnier ◽  
H. Vahabi ◽  
L. Ferry ◽  
J.-M. Lopez-Cuesta
2004 ◽  
Vol 71 (1) ◽  
pp. 27-46 ◽  
Author(s):  
Richard E Lyon ◽  
Richard N Walters

Author(s):  
Agnieszka Przystaś ◽  
Milijana Jovic ◽  
Khalifah A Salmeia ◽  
Daniel Rentsch ◽  
Laurent Ferry ◽  
...  

In this work we have investigated the role of various additives (emulsifier, anti-dripping agent) and formulation procedure (pre- dispersion of solid additives in polyol via milling) which influence the flame retardancy of 6,6′-[ethan-1,2-diylbis(azandiyl)]bis(6H-dibenzo[c,e][1,2]oxaphosphin-6-oxid) (EDA-DOPO) containing flexible polyurethane foams. For comparison, the flame retardancy of two additional structurally analogues bridged 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) based compounds i.e. ethanolamine-DOPO (ETA-DOPO) and ethylene glycol-DOPO (EG-DOPO) were also evaluated together with EDA-DOPO in flexible PU foams of various formulations. The flame retardancy of three bridged-DOPO compounds depends on the type of PU formulation. For certain PU formulation containing EDA-DOPO, lower fire performance was observed. Addition of emulsifier and polytetrafluoroethylene (PTFE) to these PU formulations influenced positively the flame retardancy of EDA-DOPO/PU foams. In addition, dispersion of EDA-DOPO and PTFE via milling in polyol improved the flame retardancy of the PU foams. Mechanistic studies performed using pyrolysis combustion flow calorimetry (PCFC) and its coupling to FTIR showed no difference in the combustion efficiency of the bridged-DOPO compounds in PU foams. From these PCFC experiments we can conclude that these bridged-DOPO compounds and their decomposition products may work primarily in the gas phase as flame inhibitors. Physiochemical behavior of additives in PU formulation responsible for the improvement in the flame retardancy of PU foams was further investigated by studying the dripping behavior of the PU foams in UL 94 HB test. A high-speed camera was used to study the dripping behavior in the UL 94 HB test and results indicate a considerable reduction of a total number of melt drips and flaming drips for the flame retardant formulations. This reduction in melt drips and flaming drips during the UL 94 HB tests help PU foams achieve higher fire classification.


Polymers ◽  
2015 ◽  
Vol 7 (3) ◽  
pp. 453-467 ◽  
Author(s):  
Svetlana Tretsiakova-McNally ◽  
Paul Joseph

Materials ◽  
2019 ◽  
Vol 12 (18) ◽  
pp. 2961 ◽  
Author(s):  
Rodolphe Sonnier ◽  
Belkacem Otazaghine ◽  
Christelle Vagner ◽  
Frédéric Bier ◽  
Jean-Luc Six ◽  
...  

From a set of around 100 phosphorus-containing polymers tested in pyrolysis–combustion flow calorimetry, the contributions to flammability of two phosphorus-containing pendant groups (called 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and PO3) were calculated using an advanced method previously proposed and validated. The flammability properties include total heat release (THR) and heat release capacity (HRC) measured in standard conditions, i.e., anaerobic pyrolysis and complete combustion. The calculated contributions are in good agreement with the main modes of action of both phosphorus groups, i.e., flame inhibition for DOPO and char promotion for PO3. Moreover, the results provide first conclusions about the cooperative interaction between phosphorus and nitrogen, as well as the influence of the architecture of tested co-polymers.


2016 ◽  
Vol 134 ◽  
pp. 340-348 ◽  
Author(s):  
Rodolphe Sonnier ◽  
Amandine Viretto ◽  
Belkacem Otazaghine ◽  
Loïc Dumazert ◽  
Alexei Evstratov ◽  
...  

Materials ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1146 ◽  
Author(s):  
Aurélie Cayla ◽  
François Rault ◽  
Stéphane Giraud ◽  
Fabien Salaün ◽  
Rodolphe Sonnier ◽  
...  

Flame retardancy of polymers is a recurring obligation for many applications. The development trend of biobased materials is no exception to this rule, and solutions of flame retardants from agro-resources give an advantage. Lignin is produced as a waste by-product from some industries, and can be used in the intumescent formation development as a source of carbon combined with an acid source. In this study, the flame retardancy of polyamide 11 (PA) is carried out by extrusion with a kraft lignin (KL) and ammonium polyphosphate (AP). The study of the optimal ratio between the KL and the AP makes it possible to optimize the fire properties as well as to reduce the cost and facilitates the implementation of the blend by a melting process. The properties of thermal decomposition and the fire reaction have been studied by thermogravimetric analyzes, pyrolysis combustion flow calorimetry (PCFC) and vertical flame spread tests (UL94). KL permits a charring effect delaying thermal degradation and decreases by 66% the peak of heat release rate in comparison with raw PA. The fire reaction of the ternary blends is improved even if KL-AP association does not have a synergy effect. The 25/75 and 33/67 KL/AP ratios in PA give an intumescence behavior under flame exposure.


Polymers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2452
Author(s):  
Baljinder K. Kandola ◽  
Wiwat Pornwannachai ◽  
John Russell Ebdon

This study is based on previously reported reaction to fire properties of flax fibre-reinforced polymeric (polypropylene, PP and polylactic acid, PLA) composites, prepared by pre-treating the fabrics with different fire retardants (FRs) prior to composite preparation. It was observed that while all of these treatments were very effective in flax/PLA in terms of achieving a V-0 rating in a UL-94 test, only an organophosphonate FR was capable of achieving a V-0 rating for flax/PP. However, all fire-retardant treatments impaired the mechanical properties of the composites; the reduction was more in flax/PLA compared to flax/PP composites. To understand these effects further, here thermal analysis and pyrolysis combustion flow calorimetry of the composites and each component separately treated with FRs have been conducted and the results analysed in terms of the effect on each component so as to observe any interaction between the different components. The results indicated that in flax/PLA composites, the water released during FR catalysed dehydration-decomposition of flax may hydrolyse PLA, changing decomposition pathway of PLA to produce less flammable volatile, hence resulting in reduced flammability.


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