Table of Contents
Journal of Soft Matter
Volume 2014 (2014), Article ID 498563, 6 pages
Research Article

Burst Diaphragms Based on Carbon Black/Silica Hybrid Filler Reinforced Nitrile Rubber Compounds

1Polymer Science & Technology Division, Research Institute of Petroleum Industry, P.O. Box 14115-143, Tehran, Iran
2Process Development Department, Research Institute of Petroleum Industry, P.O. Box 14115-143, Tehran, Iran

Received 23 June 2014; Revised 25 August 2014; Accepted 25 August 2014; Published 2 September 2014

Academic Editor: Eri Yoshida

Copyright © 2014 Ali Asghar Davoodi et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Nitrile rubber (NBR) based elastomer compounds containing different carbon black/silica composition ratios were prepared using laboratory-scale two roll mill. According the cure characterization results, addition of the reinforcing filler, either carbon black or silica, shortened the optimum cure time and also scorch time of samples compared to that of pure NBR gum where the optimum cure time and scorch time both decreased with increasing the silica content of hybrid filler. Analysis of mechanical properties showed that burst strength of carbon black-rich NBR compounds was higher compared to the samples containing silica. This is presumably due to the higher elongation at break observed in NBR/silica compounds revealing lower crosslink density. In fact, adsorption of curing agents onto the functional groups present at the silica surface would be responsible for the lower crosslink density. According to the Barlow’s formula, despite the higher tensile strength of NBR/silica compounds, higher elongation at break leads to the lower burst strength of NBR/silica/carbon black diaphragms.