The effect of bio-based ingredients in isoprene rubber: A biomimetic approach to improve the dispersion of silica

The effect of phospholipid, sorbitol, and their mixed combination in silica dispersion for a fixed loading of silica and CB ratio (30/20) in isoprene rubber matrix is realized and compared with the effect of DPNR composite as well. The higher loading of silica in tyre tread compound reduces the rolling resistance of a tyre, implicating a step towards a green approach and sustainability. Herein, the bio-based ingredients were used to enhance the dispersion of silica significantly which is otherwise a challenging task in rubber industries. Among them, the phospholipid embedded compound was proved as an ideal vulcanizate for tyre tread application based on its performance. The developed composite exhibited superior elastic storage modulus, low Tan delta at 70 degrees C (rolling resistance), and significant improvement in key properties (i.e., Tan delta at 0 degrees C, heat build-up, and abrasion resistance). Moreover, a homogenous dispersion of silica filler was evidenced by morphological analysis (FE-SEM, TEM, and AFM) and a low Payne effect from the dynamic strain sweep. However, the combination of sorbitol and phospholipid evidenced an interaction between them proved from FTIR and 1H NMR analysis, which displayed an improvement in many vital properties but due to its inferior mechanical strength and Tan delta at 0 degrees C, it could not be preferred as an ideal compound. As far as the tyre tread application is concerned, the presence of phospholipid made the compound persistent in terms of its overall performance, especially a significant improvement in Tan delta at 0 degrees C than the other compounds.

Automated summary

The effect of phospholipid, sorbitol, and their mixed combination in silica dispersion for isoprene rubber matrix with a fixed loading of silica and CB ratio (30/20) was compared with the effect of DPNR composite. The higher loading of silica in tyre tread compound reduces rolling resistance, contributing to a greener and more sustainable approach. Phospholipid was proven to be an ideal vulcanizate for tyre tread application due to its superior performance, including improved elastic storage modulus, reduced Tan delta at 70 degrees C, and enhanced key properties. However, the combination of sorbitol and phospholipid showed an interaction but had inferior mechanical strength and Tan delta at 0 degrees C, making it unsuitable as an ideal compound. The presence of phospholipid in the compound significantly improved its overall performance, especially Tan delta at 0 degrees C, for tyre tread application.