Enhancing mechanical, self-healing and damping properties of dual-modified Eucommia ulmoides gum by introducing epoxy and perfluoroalkyl groups

Eucommia ulmoides gum (EUG) is a bio-based polymer with the structure of trans-1,4-polyisoprene, and easy to crystallize at room temperature, which limits its application in rubbery materials. The epoxidized EUG (E₂₆EUG) with an epoxidation degree of 26% was readily prepared and further grafted with different contents of polar perfluoroalkyl groups by ring-opening reaction of epoxy group on the E₂₆EUG backbone using perfluorocarboxylic acid as the nucleophilic reagent under mild conditions, affording the modified elastomers E_m-xEUG-F_x with enhanced mechanical properties, good self-healing performance, and improved damping properties. The vulcanized elastomers VE₂₆EUG and VE_m-xEUG-F_x also exhibited excellent mechanical and damping properties. In addition, a high damping loss value at 0 °C in dynamic mechanical spectra indicated a good wet-skid resistance of the modified EUG elastomers before and after vulcanization. This research is of great significance for extending the applications of functional EUG rubbery materials.