Mechanical and flame-retardant properties of epoxy/Mg–Al LDH composites

Layered double hydroxides (LDH) are a class of chemical compounds that can be used to modify or incorporate characteristics into a variety of thermoplastics or thermosets polymer matrices. The focus of the present work is to synthesize organo modified-LDH MgAl intercalated with glycinate, to use them to formulate epoxy composites with distinct LDH content, and to evaluate their mechanical, thermal and flame-retardant (horizontal and vertical burning) properties. The solvents used to aid LDH dispersion into the resin were acetone, chloroform and dimethylformamide. All samples containing 1%, 3% and 5% (w/w) of LDH showed self-extinguishing behavior in the vertical test and all samples containing LDH showed better performance in terms of burning rate than pristine epoxy. The mechanical properties of the composites varied based on the solvent used and the lowest concentration of LDH (1%) yielded the best performance, as expected for this kind of filler.