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

Abstract : 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-resistance. The presence of talc as a minor component, mainly in binary compositions by partial substitution of Mg(OH)2, appeared to enhance the flame-retardant properties. It acts by forming a diffusion barrier which is able to limit the transfer of degradation products and oxygen. Synergism was also noticed between talc and zinc borate at constant Mg(OH)2 loading in ternary compositions.