Upcycling of Polybutadiene Facilitated by Selenium‐Mediated Allylic Amination

Accumulation of end‐of‐life plastics presents ongoing environmental concerns. One strategy to solve this grand challenge is to invent new techniques that modify post‐consumer waste and impart new functionality. While promising approaches for the chemical upcycling of commodity polyolefins and polyaromatics exist, analogous approaches to repurpose unsaturated polymers (e.g., polybutadiene) are scarce. In this work, we propose a method to upcycle polybutadiene, one of the most widely used commercial rubbers, via a mild, metal‐free allylic amination reaction. The resulting materials have tunable thermal and surface wetting properties as a function of both sulfonamide identity and grafting density. Importantly, this approach maintains the parent alkene microstructure without evidence of olefin reduction, olefin transposition, and/or chain scission. Based on these findings, we anticipate future applications in the remediation of complex elastomers and vulcanized rubbers. Upcycling via the direct chemical functionalization of a commodity polymer is a promising strategy that introduces new value‐added properties without destroying the parent backbone. This work harnesses the power of selenium‐catalyzed C−H functionalization chemistry for the selective allylic amination of 1,4‐polybutadiene, without alkene saturation or transposition, to tune thermal and surface wetting properties.