Titre :

Efficiency of sol-gel treatments of fibres to flame retard composites?

Auteur(s) :

Samyn, Fabienne [Auteur]
174496|||Unité Matériaux et Transformations - UMR 8207 [UMET]
Duquesne, Sophie [Auteur]
Unité Matériaux et Transformations - UMR 8207 [UMET]
Bellayer, Séverine [Auteur]
Unité Matériaux et Transformations - UMR 8207 [UMET]

Titre de la manifestation scientifique :

IAFSS 2017

Ville :

Lund

Pays :

Suède

Date de début de la manifestation scientifique :

2017-06

Discipline(s) HAL :

Sciences de l'ingénieur [physics]/Matériaux
Sciences de l'ingénieur [physics]/Génie des procédés
Chimie/Matériaux
Chimie/Polymères

Résumé en anglais : [en]

Flame retardancy of natural fibres/thermoplastic (NF/TP) composites is gaining interest since the end of Life of materials is raising growing concerns. The reversibility of the processing obtained with the thermoplastics ...
Lire la suite >Flame retardancy of natural fibres/thermoplastic (NF/TP) composites is gaining interest since the end of Life of materials is raising growing concerns. The reversibility of the processing obtained with the thermoplastics compared to thermosets is a clear asset that offers recyclability opportunities for the used materials. Different approaches have already been evaluated to flame retard NF/TP composites such as treating the matrix, coating the surface of the composites or modifying the fibres. In the latter case, the numerous approaches developed for textiles applications could, in theory, be used to produce FR composites. However, the actual use of these solutions in composites is not very well documented. A few examples have demonstrated the conception of FR composites thanks to fibres treated with aqueous solutions of soluble FRs, to the grafting of FR on the surface of the fibres and to the use of sol-gel to impart flame retardant properties to PP or PLA/flax composite. In the present work, the efficiency of sol-gel treatment to flame retard PA11/flax fabric composites is investigated. Different sol-gels have been prepared and used to treat the fabrics. A reference material including sol-gel based on tetraethylorthosilicate (TEOS) was prepared. Then, sol-gel containing phosphorous and/or nitrogen was considered combining TEOS and co-precursors (DEPTES: diethylphosphatoethyltriethoxysilane, APTES: (3-Aminopropyl)triethoxysilane) or additives (OP1230: AlPi or OP1311: AlPi-MPP). For the fibres treated using three precursors at the same time, two approaches were followed: a ‘one pot’ route (TEOS/DEPTES/APTES added all together) or a ‘layer by layer’ approach (three successive layers: TEOS, TEOS/DEPTES, TEOS/APTES). The impact of the concentrations of precursor(s) was also considered. The quality of the deposit of the sol-gel treatments has been characterized using SEM, EPMA and 29Si and 31P solid state NMR. With TEOS alone or when combined with DEPTES, quite homogeneous deposits presenting well condensed Si units (meanly Q units) are obtained whereas when combined with APTES, the deposit presents agglomerates and poor condensation of the Si network. For the sol-gel including additives, the silicon is evenly dispersed on the fibers but the FR additives aggregate on the fibers. The efficiency in terms of fire performances has been evaluated using horizontal flame spread measurements. The following ranking can be done with the different systems: TEOS + Additives > TEOS > TEOS + DEPTES ~ TEOS + DEPTES + APTES > Layer-by-layer. On the basis of these results, the better solutions have been selected and 4plies flax/PA11 composites have been prepared by film stacking. The use of sol-gel containing TEOS leads to a reduced time to ignition. The addition of phosphorous partially prevents this phenomena however no additional beneficial effect was observed.Lire moins >

Langue :

Anglais

Audience :

Internationale

Vulgarisation :

Non

Établissement(s) :

Université de Lille
ENSCL
INRA
CNRS

Collections :

• Unité Matériaux et Transformations (UMET) - UMR 8207

Équipe(s) de recherche :

Ingénierie des Systèmes Polymères

Date de dépôt :

2019-05-17T11:38:50Z
2023-01-03T13:37:37Z