Enhancing viscoelastic and mechanical performances of natural rubber through variation of large and small rubber particle combinations

There have been several reports investigating independent properties of large- (LRP) and small rubber particles (SRP). This work envisaged that, when co-existing, they could offer exceptional viscoelastic and mechanical properties from both components. Latex samples of various mixing ratios were prepared and properties of their rubber films were investigated against those of pure LRP and SRP to find that those containing 10–30% SRP were the best in mechanical strength and elasticity. This could be due to the combination of stronger phospholipid linkages in the LRP and void-filling ability of the SRP. The presence of SRP was shown to enhance curability in the vulcanised samples resulting in better mechanical performance of the vulcanisates. The 70/30 (LRP/SRP) blend showed the best thermal aging resistance among the vulcanisates. This suggested that the mixing ratios of the LRP and SRP contents were tunable to improve desirable properties of rubber products of interest, both green and cured.