Reactive compatibilization of PC/PVDF polymer blends by zinc carboxylate containing poly(methylmethacrylate) ionomers

Polycarbonate (PC) has been reacted with a random copolymer of methylmethac rylate and 6 mol% of acrylic acid (poly(MMA-co-AA)) and with this copolymer neutralized (totally or not) by Zn cations. When conducted in solution at 240 degrees C, the reaction leads to the grafting of PC onto the copolymer neutralized or not. In the melt at 235 degrees C, the grafting reaction occ urs only when the copolymer is at least partly neutralized. Whatever the ex perimental conditions (solution or bulk), PMMA does not react with PC, whic h confirms that the acidolysis of PC is at the origin of the grafting react ion. Poly(vinylidene fluoride) (PVDF) and PC have been melt blended at 235 degre es C in the presence of the poly(MMA-co-AA) copolymer totally neutralized o r not by Zn cations, the purpose being the reactive formation of PMMA-g-PC copolymer that would act as compatibilizer for the PC/PVDF blend. The phase morphology and the mechanical properties of the compatibilized PC/PVDF ble nds have been compared with the parent non-reactive polyblends. Compared to the modification of PVDF by 20 wt% of PMMA, the use of 20 wt% of the partl y neutralized poly(MMA-co-AA) copolymer decreases further the average size of the dispersed phase, enhances its adhesion to the matrix, and results in a considerable increase of the elongation at break. The beneficial effect of zinc carboxylate in the PMMA copolymer is explained by the grafting of P C onto PMMA at the interface. (C) 2000 Published by Elsevier Science Ltd. A ll rights reserved.