The Effect of Carbon Black on the Properties of Magnetic Ferrite Filled Natural Rubber Composites

The effect of carbon black loading and type on the properties of ferrite filled natural rubber (NR) composites was investigated. The carbon black loading used was from 0 to 50 phr and ferrite loading was fixed at 80 phr. Carbon black grades N330 and N660 were used in this work. The scorch time decreased with the addition of carbon black in ferrite filled NR composites whereas the cure time increased. The tensile strength and elongation at break of ferrite filled natural rubber composites were found to decrease with the increase of both types carbon black loading. However, the stress at 100% elongation (M100) and stress modulus at 300% elongation (M300) exhibit an increasing trend. The microstructure showed that filler dispersion of ferrite filled natural rubber composites become poorer with increasing carbon black loading. The thermal stability was found to enhance with carbon black loading. The swelling test indicated that the swelling percentage reduced with increasing carbon black loading while at low loading enhanced the magnetic properties of the composites. The N330 carbon black filled NR composites showed longer scorch and cure times and better tensile properties, swelling resistance and magnetic properties but lower thermal stability than N660 carbon black filled NR composites.