Zitieren Sie bitte immer diesen URN: urn:nbn:de:kobv:b43-1486
Wirkungsmechanismen von Rotem Phosphor als Flammschutzmittel in Thermoplasten
- Das Brandverhalten von Rotem Phosphor in HIPS, PBT und PA66 wurde untersucht. Es wurde gezeigt, wie die Wirksamkeit von Rotem Phosphor in HIPS and PBT durch Kombination mit anderen Flammschutzmitteln zu verbessern ist.
- Polymers are flammable due to their chemical nature. As a consequence they must be treated with flame-retardants before they can be used in fields with high flammability risks, such as transport, electronic devices and building construction. The use of red phosphorus as a fire retardant has been encouraged because it is an environmentally friendly alternative to halogenated compounds. The intention of this thesis was to evaluate the potential of red phosphorus as a flame retardant and to determine its fire-retardant mechanisms in different thermoplastics. The thermal decomposition and combustion behaviour of HIPS, PBT and PA66 containing red phosphorus was studied. It further investigated how the activity and efficiency of red phosphorus in HIPS and PBT was influenced by additional flame retardants such as melamine polyphosphate, melamine cyanurate and magnesium hydroxide. The decomposition process was characterized by means of different thermogravimetric methods (TG-FTIR,Polymers are flammable due to their chemical nature. As a consequence they must be treated with flame-retardants before they can be used in fields with high flammability risks, such as transport, electronic devices and building construction. The use of red phosphorus as a fire retardant has been encouraged because it is an environmentally friendly alternative to halogenated compounds. The intention of this thesis was to evaluate the potential of red phosphorus as a flame retardant and to determine its fire-retardant mechanisms in different thermoplastics. The thermal decomposition and combustion behaviour of HIPS, PBT and PA66 containing red phosphorus was studied. It further investigated how the activity and efficiency of red phosphorus in HIPS and PBT was influenced by additional flame retardants such as melamine polyphosphate, melamine cyanurate and magnesium hydroxide. The decomposition process was characterized by means of different thermogravimetric methods (TG-FTIR, TG-MS), and the combustion behaviour by cone calorimeter measurements at various external heat fluxes. The flammability was investigated with LOI and the residue of combustion was analysed by means of XPS. Based on these results models for decomposition process were postulated. Red phosphorus can act both by promoting char formation in the condensed phase, and through radical trapping in the gas phase. Red phosphorus acts in the condensed phase in PA66, and in the gas phase in HIPS. In PBT both mechanisms were observed, depending on the pH value. When red phosphorus is combined with fuel-dilution additives such as melamine species in HIPS and PBT, both flame retardants act independently. The combustion behaviour of the combined material can be described by superposition of the distinct flame-retarded materials. In the presence of a barrier former, such as magnesium hydroxide in HIPS, the gas-phase mechanism of red phosphorus remains unaffected; however, a slight anti-synergism results. This is based on formation of a magnesium phosphate barrier, which influences the efficiency of phosphorus as a radical trap. The results showed that the activity of phosphorus as a flame retardant in thermoplastics depends on the water content of the polymer, the pH value and the presence of functional groups in the polymer. The efficiency of phosphorus as a flame retardant in the condensed and gas phases depends on combustion conditions.…
Autor*innen: | Ulrike BraunORCiD |
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Dokumenttyp: | Dissertation |
Veröffentlichungsform: | Eigenverlag BAM |
Schriftenreihe (Bandnummer): | BAM Dissertationsreihe (10) |
Sprache: | Deutsch |
Jahr der Erstveröffentlichung: | 2005 |
Veröffentlichende Institution: | Bundesanstalt für Materialforschung und -prüfung (BAM) |
Herausgeber (Institution): | Bundesanstalt für Materialforschung und -prüfung (BAM) |
Titel verleihende Institution: | Freie Universität Berlin, Fachbereich Biologie, Chemie, Pharmazie |
Gutachter*innen: | Manfred Hennecke, Hartwig Baumgärtel |
Datum der Abschlussprüfung: | 01.12.2004 |
Verlag: | Wirtschaftsverlag NW |
Verlagsort: | Bremerhaven |
Jahrgang/Band: | 10 |
Erste Seite: | 1 |
Letzte Seite: | 164 |
DDC-Klassifikation: | Technik, Medizin, angewandte Wissenschaften / Chemische Verfahrenstechnik / Chemische Verfahrenstechnik |
Freie Schlagwörter: | Flammschutzmittel; Roter Phosphor; Thermoplasten |
URN: | urn:nbn:de:kobv:b43-1486 |
ISSN: | 1613-4249 |
ISBN: | 978-3-86509-303-5 |
Verfügbarkeit des Dokuments: | Datei für die Öffentlichkeit verfügbar ("Open Access") |
Lizenz (Deutsch): | Allgemeines Deutsches Urheberrecht |
Datum der Freischaltung: | 23.01.2015 |
Referierte Publikation: | Nein |