Study on the crosslinking network and mechanical properties of Taraxacum kok-saghyz natural rubber

The crosslinking network and mechanical properties of Taraxacum kok-saghyz natural rubber (TKNR), a promising alternative to traditional natural rubber (NR), have been underexplored. In this work, TKNR, NR, and their blends (TKNR-NR) were systematically investigated to reveal their unique crosslinking network and mechanical behaviors. Equilibrium swelling tests were conducted to measure the crosslinking density ( v ), molecular weight between crosslinks ( M c ), and swelling ratio ( Q ). The processing rheological properties of Taraxacum kok-saghyz rubber were analyzed using rubber process analyzer testing. The vulcanization behavior and mechanical performance were analyzed using standard mechanical tests, the Mooney-Rivlin equation, tube model fitting, and dynamic mechanical analysis, thereby elucidating the crosslinking network characteristics of TKNR and their correlation with mechanical properties. Results show that TKNR possesses a higher crosslinking density ( v ) and a lower M c compared to NR, resulting in reduced stiffness and strength but enhanced flexibility, elongation at break, and storage modulus. TKNR’s high crosslink density and low molecular weight between crosslinks increase hardness but restrict chain mobility, inhibiting strain-induced crystallization and reducing tensile strength. These differences are attributed to the predominance of physical entanglements ( G e ) over chemical crosslinks ( G c ) in TKNR, while NR maintains a balanced G c and G e . Blending TKNR with NR yields composites with intermediate crosslinking network and mechanical properties, achieving a balance of the two materials’ advantages.