Effect of MAH-g-PP on the Performance of ATH filled NR/PP Thermoplastic Vulcanisates.

ATH filled NR/PP thermoplastic vulcanisates (TPVs) were obtained from blending natural rubber (NR), polypropylene (PP) and alumina trihydrate (ATH) by using Brabender plastograph. Maleic anhydride grafted polypropylene (MAH-g-PP) was used as compatibiliser to improve mechanical and flammability properties of TPVs. The effect of MAH-g-PP at different concentrations on the properties of ATH filled NR/PP TPVs was studied. Investigation on the microstructures of ATH filled NR/PP TPVs by mean of scanning electron microscope (SEM) and transmission electron microscope (TEM) indicated the efficient mixing of NR and PP phases and more uniform distribution of ATH in individual component of NR/PP blend due to compatibilising action of MAH-g-PP. Mechanistic model for the compatibilisation process of a structure of ATH filled NR/PP TPVs in the presence of MAH-g-PP was also proposed. With higher concentration of MAH-g-PP, the TPVs had shown increase in 100% modulus, increase in tensile strength, decrease in elongation at break and less elastic recovery. The flame resistance also increased with the addition of given amount of MAH-g-PP. However, the addition of MAH-g-PP had little influence on processing capability of the ATH filled NR/PP TPVs. Based on the present study, it was suggested that the MAH-g-PP acted as compatibility enhancer in the ATH filled NR/PP TPVs and the compatibility increase was a key to benefit the strength and flame retardancy of the NR/PP TPVs. [ABSTRACT FROM AUTHOR]