Terpene-Derived Bioelastomers for Advanced Vulcanized Rubbers and High-Impact Acrylonitrile–Butadiene–Styrene

The increasing demand for sustainable materials has propelled the development of bio-based elastomers derived from renewable terpenes. This study presents the synthesis of high-cis poly(butadiene-co-terpene) copolymers using coordination chain transfer polymerization with neodymium-based catalysts, enabling precise control of molecular weight and microstructure. Two terpene monomers, β-myrcene and trans-β-farnesene, were incorporated up to 45 wt% without compromising the elastomeric 1,4-cis polybutadiene segments. The copolymers were evaluated as impact modifiers in acrylonitrile–butadiene–styrene (ABS) and as vulcanizable rubber formulations. ABS containing bio-based copolymers exhibited distinct rubber morphologies, including elongated and rod-like particles with average particle diameters greater than 1042 nm and rubber phase volume fraction values ≥ 0.49, resulting in improved impact resistance exceeding 580 J/m and elongation at break higher than 12%. Vulcanized rubbers incorporating terpene segments displayed tunable curing kinetics, mechanical properties, and dynamic mechanical behavior, with notable increases in elongation (up to ~520%) and elasticity attributed to lower crosslink density (<1.20 × 10−4 mol/mL). Additionally, its energy dissipation capacity has been enhanced compared to the high-cis polybutadiene. These findings highlight the potential of terpene-derived bioelastomers as sustainable alternatives to fossil-based rubbers, offering comparable or enhanced performance for engineering polymer applications. The study underscores important structure–property relationships, providing a foundation for further optimization toward industrial adoption.