The preparation and characterization of a novel self-healing based on the dynamic translocation of disulfide bonds

A novel self-healing poly(urea-urethane) elastomer materials was prepared through the two-step method. These materials utilize the dynamic translocation of disulfide bonds to improve the self-healing ability. When key preparation parameters the isocyanate index and the mass ratio of two prepolymers are R = 1.2 and 6:4, the prepared poly(urea-urethane) elastomer is suitable for preparing the modified asphalt. Thermogravimetric analysis has shown that this self-healing materials can be stable below 260 °C. Fourier transform infrared spectra demonstrated that the hydrogen bonds were formed between adjacent molecules, and played an important role in the early stage of the materials self-heal. The self-healing ability of poly(urea-urethane) was tested by the direct tensile test after fracture-heal. The healing efficiency of the poly(urea-urethane) samples are 58.6%, 80.5%, 94.3% at room temperature, after 1 h, 2 h, 12 h, respectively. By fluorescence microscopy, poly(urea-urethane) elastomer was uniformly dispersed in the matrix asphalt without agglomeration.