Despite its current limited availability, hemp is raising interest for green composite manufacturing, as it is cheap renewable resource and shows low density, high specific strength with respect to glass or aramid fibers and good biodegradability as well. In this work, the flame retardancy of hemp fabric/epoxy composites is investigated, exploiting either the in situ formation of silica nanoparticles in the epoxy epoxy or specific surface treatments of hemp fabrics with acidified waterglass solutions. To this aim, Tetraethoxysilane (TEOS) and 3-aminopropyl triethoxysilane (APTS, as coupling agent) were used as silica precursors in a commercially available bisphenol resin cured with cicloaliphatic polyamines. The final curable mixture was fluid enough to assure good impregnation of the hemp fabrics. Composites were produced through impregnation of 6 hemp fabric layers with the mixture of silica containing epoxy resin and curing agent. The cure was performed at room temperature for 15 d. The fire behavior of the composites was assessed by cone calorimetry tests and the results were compared to those obtained for the same systems without silica nanoparticles and hemp surface treatment. These modifications promoted a significant reduction of heat release rate (35%), as well as an important decrease of the released smokes (namely, -8% of total smoke release and -21% of specific extinction area).

Silica treatments: a fire retardant strategy for hemp fabric/epoxy composites / Branda, F.; Malucelli, Giulio; Durante, M.; Costantini, A.; Silvestri, B.; Pennetta, M.. - STAMPA. - (2016), pp. 35-35. (Intervento presentato al convegno COST MP1105 Final Conference tenutosi a Poznan nel 27-28 April 2016).

Silica treatments: a fire retardant strategy for hemp fabric/epoxy composites

MALUCELLI, Giulio;
2016

Abstract

Despite its current limited availability, hemp is raising interest for green composite manufacturing, as it is cheap renewable resource and shows low density, high specific strength with respect to glass or aramid fibers and good biodegradability as well. In this work, the flame retardancy of hemp fabric/epoxy composites is investigated, exploiting either the in situ formation of silica nanoparticles in the epoxy epoxy or specific surface treatments of hemp fabrics with acidified waterglass solutions. To this aim, Tetraethoxysilane (TEOS) and 3-aminopropyl triethoxysilane (APTS, as coupling agent) were used as silica precursors in a commercially available bisphenol resin cured with cicloaliphatic polyamines. The final curable mixture was fluid enough to assure good impregnation of the hemp fabrics. Composites were produced through impregnation of 6 hemp fabric layers with the mixture of silica containing epoxy resin and curing agent. The cure was performed at room temperature for 15 d. The fire behavior of the composites was assessed by cone calorimetry tests and the results were compared to those obtained for the same systems without silica nanoparticles and hemp surface treatment. These modifications promoted a significant reduction of heat release rate (35%), as well as an important decrease of the released smokes (namely, -8% of total smoke release and -21% of specific extinction area).
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11583/2641171
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo