ELASTOMERIC BLENDS OF CARBOXYLATED NITRILE RUBBER AND POLYSULFIDE RUBBERS

The blends of carboxylated nitrile rubber, XNBR, with two grades of th iokol rubbers, TM, prepared by different blending techniques and at di fferent rubbers ratios, have been studied. The processability of the t hiokol rubber was improved by blending with XNBR. Blend properties lar gely depend on the blend ratios. IR spectral analysis revealed that on heating interchain crosslinking occurred between TM and XNBR. Preheat ing of the preblends, before addition of curatives, improved the prope rties of the blends. The degradation and weight loss were also retarde d. Furthermore, preheating also restricted the extractability of the X NBR phase by solvent.