INTERFACIAL MODIFICATION OF POLYPROPYLENE COMPOSITES FILLED WITH MAGNESIUM-HYDROXIDE

The mechanical behaviour of polypropylene composites containing magnesium hydroxide is considered with reference to the influence on properties of filler surface modification. Compared to composites containing untreated filler, mechanical properties can be strongly affected by the chemical nature and amount of surface treatment applied. In particular, very significant improvements in toughness are obtained using sufficiently high levels of magnesium stearate to ensure complete coverage of the magnesium hydroxide surface. Results are discussed in terms of the observed deformation mechanism in the polymer matrix.