Abstract:
Blending of two polymers usually gives rise to a new material having a better balance of properties than a single polymer. Blending of elastomers is undertaken for three main reasons: (i) improvement of the technical properties of the original elastomer, (ii) achievement of improved processing behaviour, and (iii) reduction in compound cost. In the present work, the blends of sulphur-cured chlorinated polyethylene (CPE) and natural rubber (NR) were prepared. The blend of the composition was 80/20 CPE/NR. Recyclability, mechanical and rheological properties of blends influenced by recycling cycles, the addition of magnesium oxide (MgO) and amine-based antioxidant were discussed. It was found that recycling of the 80/20 CPE/NR blends cured with the sulphur vulcanising system is possible, and their mechanical properties are not significantly affected by increasing recycling cycles. By contrast, the viscoelastic behaviour as determined from oscillatory flow is influenced strongly by recycling. The more the
recycling cycles, the higher the viscous response due to a thermal degradation via chain scission process of NR phase as evidenced by a dynamic mechanical analyses. In addition, the addition of MgO or amine-based antioxidant plays a strong role on thermal stability of the blends, particularly on the NR phase.