Cargando…

Expandable Graphite as a Multifunctional Flame-Retarding Additive for Highly Filled Thermal Conductive Polymer Formulations

Expandable graphite (EG) and graphite (G) were assessed as multifunctional additives improving both flame retardancy and thermal conductivity in highly filled, thermal conductive polymeric materials based on polyamide 6 (PA6). Fire testing was conducted using modern UL-94, LOI and cone calorimeter t...

Descripción completa

Detalles Bibliográficos
Autores principales: Tomiak, Florian, Schneider, Kevin, Schoeffel, Angelina, Rathberger, Klaus, Drummer, Dietmar
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2022
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9031968/
https://www.ncbi.nlm.nih.gov/pubmed/35458364
http://dx.doi.org/10.3390/polym14081613
_version_ 1784692523950669824
author Tomiak, Florian
Schneider, Kevin
Schoeffel, Angelina
Rathberger, Klaus
Drummer, Dietmar
author_facet Tomiak, Florian
Schneider, Kevin
Schoeffel, Angelina
Rathberger, Klaus
Drummer, Dietmar
author_sort Tomiak, Florian
collection PubMed
description Expandable graphite (EG) and graphite (G) were assessed as multifunctional additives improving both flame retardancy and thermal conductivity in highly filled, thermal conductive polymeric materials based on polyamide 6 (PA6). Fire testing was conducted using modern UL-94, LOI and cone calorimeter test setups. It is demonstrated that thermal conductivity can significantly influence the time to ignition, although offering little fire resistance once ignited even in highly filled systems. Thus, for PA6 formulations containing solely 70 wt.% G, the peak heat release rate (pHRR) measured in cone calorimeter tests was 193 kW/m², whereas PA6 formulations containing 20 wt.% EG/50 wt.% G did not exhibit a measurable heat development. Particular attention was paid to effect separation between thermal conductivity and residue formation. Good thermal conductivity properties are proven to be particularly effective in test scenarios where the heat impact is comparatively low and the testing environment provides good heat dissipation and convective cooling possibilities. For candle-like ignition scenarios (e.g., LOI), filling levels of >50 wt.% (G or EG/G) are shown to be sufficient to suppress ignition exclusively by thermal conductivity. V0 classifications in UL-94 vertical burning tests were achieved for PA6 formulations containing ≥70 wt.% G, ≥25 wt.% EG and ≥20 wt.% EG/25 wt.% G.
format Online
Article
Text
id pubmed-9031968
institution National Center for Biotechnology Information
language English
publishDate 2022
publisher MDPI
record_format MEDLINE/PubMed
spelling pubmed-90319682022-04-23 Expandable Graphite as a Multifunctional Flame-Retarding Additive for Highly Filled Thermal Conductive Polymer Formulations Tomiak, Florian Schneider, Kevin Schoeffel, Angelina Rathberger, Klaus Drummer, Dietmar Polymers (Basel) Article Expandable graphite (EG) and graphite (G) were assessed as multifunctional additives improving both flame retardancy and thermal conductivity in highly filled, thermal conductive polymeric materials based on polyamide 6 (PA6). Fire testing was conducted using modern UL-94, LOI and cone calorimeter test setups. It is demonstrated that thermal conductivity can significantly influence the time to ignition, although offering little fire resistance once ignited even in highly filled systems. Thus, for PA6 formulations containing solely 70 wt.% G, the peak heat release rate (pHRR) measured in cone calorimeter tests was 193 kW/m², whereas PA6 formulations containing 20 wt.% EG/50 wt.% G did not exhibit a measurable heat development. Particular attention was paid to effect separation between thermal conductivity and residue formation. Good thermal conductivity properties are proven to be particularly effective in test scenarios where the heat impact is comparatively low and the testing environment provides good heat dissipation and convective cooling possibilities. For candle-like ignition scenarios (e.g., LOI), filling levels of >50 wt.% (G or EG/G) are shown to be sufficient to suppress ignition exclusively by thermal conductivity. V0 classifications in UL-94 vertical burning tests were achieved for PA6 formulations containing ≥70 wt.% G, ≥25 wt.% EG and ≥20 wt.% EG/25 wt.% G. MDPI 2022-04-15 /pmc/articles/PMC9031968/ /pubmed/35458364 http://dx.doi.org/10.3390/polym14081613 Text en © 2022 by the authors. https://creativecommons.org/licenses/by/4.0/Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Tomiak, Florian
Schneider, Kevin
Schoeffel, Angelina
Rathberger, Klaus
Drummer, Dietmar
Expandable Graphite as a Multifunctional Flame-Retarding Additive for Highly Filled Thermal Conductive Polymer Formulations
title Expandable Graphite as a Multifunctional Flame-Retarding Additive for Highly Filled Thermal Conductive Polymer Formulations
title_full Expandable Graphite as a Multifunctional Flame-Retarding Additive for Highly Filled Thermal Conductive Polymer Formulations
title_fullStr Expandable Graphite as a Multifunctional Flame-Retarding Additive for Highly Filled Thermal Conductive Polymer Formulations
title_full_unstemmed Expandable Graphite as a Multifunctional Flame-Retarding Additive for Highly Filled Thermal Conductive Polymer Formulations
title_short Expandable Graphite as a Multifunctional Flame-Retarding Additive for Highly Filled Thermal Conductive Polymer Formulations
title_sort expandable graphite as a multifunctional flame-retarding additive for highly filled thermal conductive polymer formulations
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9031968/
https://www.ncbi.nlm.nih.gov/pubmed/35458364
http://dx.doi.org/10.3390/polym14081613
work_keys_str_mv AT tomiakflorian expandablegraphiteasamultifunctionalflameretardingadditiveforhighlyfilledthermalconductivepolymerformulations
AT schneiderkevin expandablegraphiteasamultifunctionalflameretardingadditiveforhighlyfilledthermalconductivepolymerformulations
AT schoeffelangelina expandablegraphiteasamultifunctionalflameretardingadditiveforhighlyfilledthermalconductivepolymerformulations
AT rathbergerklaus expandablegraphiteasamultifunctionalflameretardingadditiveforhighlyfilledthermalconductivepolymerformulations
AT drummerdietmar expandablegraphiteasamultifunctionalflameretardingadditiveforhighlyfilledthermalconductivepolymerformulations