Condensed‐phase flame retardation in nylon 6‐layered silicate nanocomposites: Films, fibers, and fabrics

Abstract

Flame‐retardant properties of nylon 6/organically modified montmorillonite (OMMT) thin films, fibers, and fabrics were investigated to determine the efficacy of condensed‐phase flame‐retardant mechanism in relation to montmorillonite concentration, sample geometry, and flame test conditions. Horizontal flame spread conducted on thin films revealed no significant difference in burning behavior between nylon 6 and nanocomposites with 5 wt% OMMT. However, with a higher concentration level of 8–10 wt% OMMT, the films burned without any dripping. The flame spread rate was reduced by 30–40% as compared with nylon 6 films. Cone calorimeter study on nanocomposite films showed that the peak heat release rate of nylon 6 was reduced by 65–67% with 8–10 wt% OMMT. Undrawn nanocomposite monofilaments with 10 wt% OMMT burned slowly and steadily in Bunsen flame without dripping. In cone calorimeter, nanocomposite fabrics with 8 wt% OMMT showed reduced heat release rate and mass loss rate compared to nylon 6 fabrics with increase in fabric tightness factor. The mass loss rate was about 40–60% less when compared with nylon 6 fabrics. The fabric char structure remained intact after burning. This demonstrated the interdependence of fabric tightness factor, OMMT concentration, and source of heat flux in forming a protective char and affecting the flammability of fabrics. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers

Intumescent flame retardation of melamine‐modified montmorillonite on polyamide 6: Enhancement of condense phase and flame retardance

“…Halogen‐free flame retardants for PA6 include red phosphorus, [5, 6] melamine‐based products, [7, 8] organically phosphorus‐containing flame retardant, [9, 10] magnesium hydroxide, [11, 12] etc. Recently, many researchers pay more attention to polymer/clay nanocomposites which is believed to be one of the most promising approaches in flame retardance [13–16]. As reported, improved flame retardance of polymer/clay nanocomposites was exhibited such as the reduction of the flame spread, peak of heat release rate (PHRR), total heat release (THR), and so on [17–21].…”

Segregated Networks of Carbon Black in Poly(vinyl acetate) Latex: Influence of Clay on the Electrical and Mechanical Behavior

“…Several others have found that clay can significantly reduce the percolation threshold at relatively low concentrations (<5 wt.-%). [41,43,45] Clay continues to be heavily studied for its ability to improve the mechanical, [46][47][48][49] transport, [50][51][52] and flame retardant [53][54][55] properties of polymers, but it has received little attention as a synergistic filler in conductive composites. In one case, the percolation threshold of carbon black filled nylon 6 was reduced from 15.5 to 5.8 vol.-% with the addition of 3 vol.-% clay.…”

Environmentally friendly flame-retardant textiles

“…The surface of the fi bres will be fuel-rich, and their high surface area could lead to enhanced oxygen contact and turbulent combustion. 60 Horrocks and Kandola 61 have aptly pointed to the physical and thermally thin structure of textile materials as the key to this inefficiency. For such thermally thin materials, they suggested that the 'shieldforming' mechanism could be too slow for any effective improvement in fi re performance and that the presence of nanoclay alone in fi bres, fi lms and textiles may not be suffi cient to impart fl ame retardancy at higher heat fl uxes.…”

“…However, the processing of polymer-clay nanocomposites is challenging in terms of maintaining nano-dispersion and the infl uence of nanoparticles on rheological properties can be crucial in fi bre extrusion. Very few studies 50,60,[64][65][66][67][68][69] are reported in the literature wherein the polymer-clay nanocomposite fi bres are extruded and fl ammability properties tested on the fabrics woven/knitted from such composite fi bres. Devaux et al 70 and Horrocks et al 43 have reported on the inclusion of nanocomposite coatings.…”