Thermoplastic elastomers based on ionomeric polyblends of zinc salts of poly(propylene-co-acrylic acid) and carboxylated nitrile rubber

Abstract

Ionomeric polyblends of zinc salt of carboxylated nitrile rubber, abbreviated as Zn-XNBR and zinc salt of poly(propylene-co-acrylic acid), abbreviated as Zn-PPA, were prepared by melt blending. The ionomeric polyblends of Zn-XNBR/Zn-PPA in the compositions of 90/10 and 80/20, parts by weight, behave as ionic thermoplastic elastomers and exhibit synergism in properties. The ionomeric polyblend shows superior physical properties than the corresponding non-ionomeric polyblend. The synergism and superior physical properties of the ionomeric polyblends are attributed to the formation of strong intermolecular ionic interactions between the component polymers, as observed by the infrared spectroscopic studies. Dynamic mechanical thermal analyses reveal that besides glass-rubber transition in the low temperature region, the neat ionomers and the ionomeric polyblends show a high temperature transition owing to the relaxation of the restricted mobility chain segments in the ionic cluster region. The reprocessability studies reveal the thermoplastic elastomeric nature of the ionomeric polyblend.