Palm-based process aid as an alternative to naphthenic oil for deproteinised natural rubber compounding

This study evaluates the effects of an eco-friendly, safe and sustainable bio-based process aid (BIO) that was synthesised from palm oil derivatives as an alternative to commercial petroleum-based naphthenic oil (CO) for deproteinised natural rubber (DPNR) compounding. Results revealed that the use of BIO improves the processability of rubber during compounding. Tensile properties of composites were comparable to each other. Interestingly, the use of the palm-based plasticiser caused an increase in hardness and higher compression sets of DPNR composites compared to DPNR composites with CO. Ageing study suggests that BIO-DPNR composites have better elastomeric property due to lower compression sets compared to CO-DPNR composites. Fourier transform infrared (FTIR) spectra exhibited attenuated peaks at 3400–3100, 1539, and 838 cm −1 of all aged composites. Thermogravimetric analysis (TGA) showed that all composites have one degradation stage between 200 and 450 °C and the thermal stability of BIO-DPNR composites was comparable to the control and CO-DPNR composites. Transmission electron microscopy (TEM) micrograph demonstrated that BIO-DPNR composites have a more homogenous distribution of carbon black with smaller agglomerates. The findings of this study show the potential of BIO as an alternative to naphthenic oil for deproteinised natural rubber compounding. The produced BIO-DPNR composite could also emerge as a new green material that is more environmental friendly, sustainable and safe for various applications, particularly where ageing properties are essential such as engineering and automotive products.