Magnesium hydroxide/zinc borate/talc compositions as flame-retardants in EVA copolymer

The fire-resistance of EVA filled with ternary systems (magnesium hydroxide /zinc borate/talc) has been investigated. The release of water from Mg(OH)( 2) seemed to be the predominant phenomenon which acts in relation to fire-r esistance. The presence of talc as a minor component, mainly in binary comp ositions by partial substitution of Mg(OH)(2), appeared to enhance the flam e-retardant properties. It acts by forming a diffusion barrier which is abl e to limit the transfer of degradation products and oxygen. Synergism was a lso noticed between talc and zinc berate at constant Mg(OH)(2) loading in t ernary compositions. (C) 2000 Society of Chemical Industry.