CHARACTERIZATION OF NATURAL RUBBER/CASSAVA STARCH/MALEATED NATURAL RUBBER FORMULATIONS

The objective of this research study was to study the rheological and tensile behavior of natural rubber (NR) compounds with cassava starch (CS) and plasticized cassava starch (PCS), with the aim of using cassava as potential filler for NR vulcanizates. The authors also evaluated the synthesis and use of maleated Natural Rubber (MNR) as a coupling agent. The results obtained indicate that the presence of CS originates changes such as an increase in the maximum torque and a slight reduction in scorch and curing time. The addition of MNR to the blends of NR with and without CS also retarded the curing process. With regard to the mechanical properties, 20 phr of CS did not alter the tensile properties of the NR vulcanizates, so a cheaper formulation with equivalent properties can be obtained. The properties of the compounds with PCS were similar to those of the NR/CS compounds. Concerning the use of MNR as a coupling agent, it did not improve the overall properties of NR. Finally, the thermal degradation behavior of NR was not affected by the addition of CS, while the use of PCS accelerated the degradative process of NR.