Sustainable Eucommia ulmoides gum (EUG) was a biomaterial with the molecular structure of trans-1,4-polyisoprene and poor elasticity, and was usually considered as a hard rubber with a limited applications in rubber products. Triazolinedione (TAD)-based Alder-ene reaction was used to modify EUG to precisely tune the mechanical properties and effectively improve the elasticity by reducing crystallinity, introducing urazole groups, and forming hydrogen bonds between EUG molecules. By adjusting TAD feed, the modified EUG could become an excellent tough elastomer with combined high strength, elongation, and toughness; or a unique rubber with superhigh elongation, low Young's modulus, and good elastic recovery rate. Furthermore, the modified EUG displayed enhanced shape memory capability with fast shape recovery speed, high cyclic shape recovery rate after 10-cycle deformations, and large shape memory recoverable deformation. Therefore, these elastomers may have extended applications in tires and smart materials.

可持续的杜仲胶（EUG）是具有反式分子结构的生物材料-1,4-聚异戊二烯和较差的弹性，通常被认为是硬橡胶，在橡胶产品中的应用受到限制。基于三唑啉二酮（TAD）的Alder-ene反应通过修饰EUG来精确调节机械性能，并通过降低结晶度，引入脲基并在EUG分子之间形成氢键来有效地提高弹性。通过调整TAD进料，改性的EUG可以成为兼具高强度，伸长率和韧性的优异韧性弹性体。或具有超高伸长率，低杨氏模量和良好弹性回复率的独特橡胶。此外，改进的EUG显示出增强的形状记忆能力，具有快速的形状恢复速度，十个循环变形后的高循环形状恢复率以及大的形状记忆可恢复变形。所以，