Self-healing silicon-containing eugenol-based epoxy resin based on disulfide bond exchange: Synthesis and structure-property relationships

The research of biobased multifunctional self-repairing and cross-linking epoxy resins with excellent mechanical properties is meaningful and should be further fabricated and developed. Herein, a biobased double functional epoxy monomer modified with organosilicon (EETS) was derived from eugenol and 1,1,3,3-tetramethyldisiloxane, and cured by 4-aminophenyl disulfide (APDS) to form the disulfide bond dynamic epoxy EETS/APDS resins. The combination properties of EETS/APDS resin were studied systemically. Results demonstrated that the EETS/APDS had lower glass transition temperature (53.03 °C) and tensile strength (38.8 MPa), and higher elongation at break (22.1%), compared with the thermoset of diglycidyl ether of bisphenol A (DGEBA/APDS). In addition, the relaxation time of EETS/APDS resin was 28 s at 200 °C. At the same time, self-repairing, shape memory, and reprocessing ability of EETS/APDS resin was exhibited by physical fracture and moderate-high temperature repair due to the rapid exchange of disulfide bonds. Furthermore, the complete degradation of the BDSER resins could be achieved. These excellent dynamic properties and bio-based monomers provide a feasible way to meet the requirements of sustainable development.