Facile strategy for incorporating hydrazide groups into bio-based elastomers to improve dispersion of carbon black and interfacial interactions

To meet the need for sustainable and high-performance elastomers, considerable efforts should be made to design and synthesize novel bio-based elastomers and develop their high-performance composites for engineering applications. Herein, starting from bio-based poly (diethyl itaconate-co-butadiene) (PDEIB), which reported first by our group, hydrazide groups were successfully introduced into the PDEIB elastomer chains via hydrazinolysis of ester groups, thereby achieving hydrazide-functionalized PDEIB ( h -PDEIB). The h -PDEIB with various contents of hydrazide groups could be facilely synthesized by simply adjusting reaction time. Model reaction demonstrated that the hydrazide groups are high reactivity and capable of forming strong interactions with oxygen-containing groups on the surface of carbon black (CB). Hence, the presence of hydrazide groups in the h -PDEIB facilitated the dispersion of CB filler and enhanced its interfacial interactions with the rubber matrix. Moreover, the h -PDEIB/CB compounds exhibited a marked increase in bound rubber content and interfacial layer thickness compared to the virgin PDEIB/CB compounds, indicating improved interfacial interactions. Consequently, the mechanical properties of the h -PDEIB/CB composites improved significantly, especially the tensile strength and modulus. And, the h -PDEIB/CB composites showed a reduced energy dissipation under dynamic deformation, consistent with improved dispersion and stronger rubber–filler interfaces. This work provides a facile strategy to synthesize bio-based hydrazide-functionalized elastomers and prepare high-performance elastomer composites with improved CB dispersion and interfacial interactions.