The properties of rubber composites depend strongly on the compatibility of the rubber matrix and particulate filler. The polarity difference between the two phases has always been the main concern. Natural rubber (NR) and halloysite nanotubes (HNT) are one of the examples of the incompatible system. In this regard, a suitable compatibilizer is recommended to mediate the interactions. In this study, the maleated natural rubber (MNR) with various amounts of maleic anhydride (MA) was introduced as a compatibilizer to this composite. By increasing MA contents, scorch and curing times were increased whereas the maximum torque and the torque differences exhibited the highest values at the MA content of 2 phr. Payne effect was also implemented to monitor their rubber-filler interactions. The MNR with 2 phr of MA exhibited the lowest filler-filler interaction as shown by a lower decrement of storage modulus at high strain. This rubber composite also exhibited the optimum tensile and tear strengths. It is clearly highlighted that application of the MNR with a suitable MA amount enables to increase the rubber-filler interaction significantly and therefore improve a HNT dispersion. Hence, the use of MNR provided the great potential to compatibilize NR and HNT.

Keywords: natural rubber, maleated natural rubber, halloysite nanotubes, Payne effect