Influence of talc physical properties on the fire retarding behaviour of (ethylene-vinyl acetate copolymer/magnesium hydroxide/talc) composites

The present work focuses on the fire retarding behaviour of (ethylene-vinyl acetate (EVA) copolymer/magnesium hydroxide (MH)/talc) composites. Talc particles of different lamellarity and specific surface area have been tested, leading to the conclusion that for highly lamellar talc particles, the fire retarding behaviour becomes similar to that of (EVA/MH/organomodified montmorillonite (oMMT)) composites, with a significant inturnescence. This intumescence, which occurs during the pre-ignition period in cone calorimeter tests, seems to be related to three phenomena caused by the presence of the lamellar particles (oMMT or talc): heterogeneous bubble nucleation, increased viscosity and charring promotion. (c) 2005 Elsevier Ltd. All rights reserved.