Covalently cross-linked rubber materials are widely used in elastic applications due to their excellent mechanical properties. However, the irreversibility of covalent cross-linking suffers from poor material recyclability. As a degradable polypeptide-based cross-linker for polybutadiene, poly(l-cysteine) (polyCys) was synthesized via papain-catalyzed chemoenzymatic polymerization. The resulting polyCys had intact thiol groups that cross-linked polybutadiene via the thiol-ene reaction. The cross-linking reaction of polybutadiene was performed in the presence of polyCys and a radical initiator and resulted in insoluble polybutadiene gel formation. Based on Raman spectroscopy analysis, the cross-linking reaction was confirmed by the consumption of thiol groups of polyCys. From the dynamic viscoelastic analyses of the cross-linked polybutadienes, the viscoelasticity drastically changed from that of raw polybutadiene, with the disappearance of the slow relaxation mode at low frequencies. The complete network formation was confirmed by E′ and E′′ showing the power law over the whole frequency range, as determined by the time-course experiments of the dynamic viscoelastic properties. The cross-linked polybutadiene was degradable by acid hydrolysis, resulting in the regeneration of soluble polybutadiene. Polypeptide cross-linked polybutadiene materials are promising candidates for the application of polybutadiene-based rubber materials with the requirements of both material integrity and reusability.

共价交联橡胶材料由于其优异的机械性能而广泛应用于弹性应用。然而，共价交联的不可逆性导致材料的可回收性较差。作为一种可降解的基于多肽的聚丁二烯交联剂，聚（半胱氨酸）（polyCys）是通过木瓜蛋白酶催化的化学酶聚合合成的。所得的多半胱氨酸具有完整的硫醇基团，可通过硫醇-烯反应交联聚丁二烯。聚丁二烯的交联反应在多半胱氨酸和自由基引发剂的存在下进行，并导致不溶性聚丁二烯凝胶的形成。基于拉曼光谱分析，通过多半胱氨酸硫醇基团的消耗证实了交联反应。从交联聚丁二烯的动态粘弹性分析来看，交联聚丁二烯的粘弹性与原始聚丁二烯相比发生了巨大变化，低频下慢弛豫模式消失。 E′ 和 E′′ 证实了完整的网络形成，显示了整个频率范围内的幂律，这是由动态粘弹性特性的时程实验确定的。交联聚丁二烯可通过酸水解降解，导致可溶性聚丁二烯再生。多肽交联聚丁二烯材料是聚丁二烯基橡胶材料应用的有前途的候选材料，具有材料完整性和可重复使用性的要求。