Stearic acid surface modifying Mg(OH)₂: Mechanism and its effect on properties of ethylene vinyl acetate/Mg(OH)₂ composites

In this article, FTIR spectra and ESEM images were employed to evaluate the effect of stearic acid surface modification of Mg(OH)₂. As a result, the absorbing peak intensity of organic group on Mg(OH)₂ increased with the coating amount of stearic acid increasing and there was no so-called surface saturation as expected. The results indicated stearic acid surface treatment of Mg(OH)₂ belonged to the acid-base reaction between stearic acid and Mg(OH)₂, and it would not stop until Mg(OH)₂ was reacted completely. In addition, stearic acid surface treatment of Mg(OH)₂ had remarkable influence on the properties of ethylene vinyl acetate/Mg(OH)₂ composites. With the increasing coating amount of stearic acid, the composites had decreased tensile strength, increased elongation at break, and deteriorated flame retardancy, compared with the composites filled with the uncoated Mg(OH)₂. However, stearic acid surface treatment of Mg(OH)₂ benefited processing ability of composites, and the composites had better processing ability as the coating amount of stearic acid increased. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008