Compatibilization of PP/Vectra B "in situ" composites by means of an ionomer

Ionomer addition has been investigated as a compatibilizer for the immiscib le polypropylene (PP)/Vectra B 950 (VB). Both modified and unmodified blend s as a reference, with VB contents up to 30% were obtained by direct inject ion moulding. The crystallinity of PP/VB was barely influenced by the prese nce of the ionomer. The compatibilization leads to the presence of thinner fibres that broke during testing. Compatibilization reduced toughness, but at VB contents of 15 wt% or more, both the modulus of elasticity and the te nsile strength significantly increased with respect to the uncompatibilized blends. The properties of both compatibilized and uncompatibilized blends, as a whole, were similar in the case of PP modified by either maleic anhyd ride or ionomer addition. However, favourable experimental conditions such as thinner specimens or higher compatibilizer content were used in the case of maleic anhydride modified PP. This indicates a more important positive effect: on compatibilization by means of ionomer addition. (C) 2000 Elsevie r Science Ltd. All rights reserved.