Preparation and Performance Study of Epoxy Resin Modified Polysiloxane Self-healing Materials

Polysiloxane materials possess excellent properties such as flexibility and chemical stability. However, due to the low cohesive energy density within the polysiloxane and the lack of polarity in the polymer chains, their mechanical properties are poor, which limits their application in the self-healing field. This paper uses polysiloxane materials to prepare self-healing elastomers by incorporating epoxy resin. Firstly, end amino polysiloxane is prepared by in situ polymerization, and then it is modified with epoxy resin, followed by the introduction of the salicylaldehyde and zinc acetate system. Through orthogonal experiments, the optimal ratio of epoxy resin modified polysiloxane self-healing material was determined: the mass ratio of PDMS : EP is 10 : 6, PDMS : SA is 10 : 1, and SA : Zn (OAc)2 is 1 : 0.2. The fracture elongation ratio reaches 700%. The results show that, under an observation with a polarizing microscope at 80°C, materials with a low crosslinking density and moderate epoxy resin content have excellent self-healing ability. The antibacterial adhesion analysis proves that the polysiloxane with Zn2+ introduced on the surface has certain antibacterial adhesion performance with the epoxy resin system. This work provides ideas for the application of functionalized polysiloxane materials in new fields.