Vitrimer is a new reprocessable thermosetting polymer based on the exchange of dynamic covalent bonds. However, the vitrimer reported in the literatures can usually be reprocessed at very high temperature, while the vitrimer reprocessed at a relatively low temperature exhibits poor mechanical properties. It is still a great challenge to design mechanically robust vitrimer with a moderate reprocessing temperature. Herein, a polyurethane‐urea vitrimer elastomer including N,N′‐diaryl urea with electron donating effect is first reported, and it possesses a moderately remoldable temperature (100 °C, 23% of soft segments content) and robust mechanic al performance. The associative exchange mechanism of N,N′‐diaryl urea with electron donating effect is investigated by the stress relaxation, variable temperature Fourier transform infrared spectra of elastomer, as well as nuclear magnetic resonance spectra, and Fourier transform infrared spectra based on model compounds. Besides, for the preparation of polyurethane‐urea vitrimer elastomers, all monomers are directly from commercial raw materials, thereby providing a possibility of large‐scale production for the polyurethane‐urea vitrimers.

Transparent self-healing polymers have a promising future, but the research on the relationship among transparency, self-healing, and structure is still challenging. The thermoplastic polyurethane elastomers containing aryl carbamate were prepared by the reaction of isocyanate-terminated prepolymer and chain-extender bisphenol A (BPA). On the one hand, the thermoplastic polyurethane elastomer could heal at a relatively low temperature due to the exchange of aryl carbamate, and exhibits 83% of healing efficiency at 90 C for 2 h. On the other hand, two methyl groups of BPA hinder the crystallization of hard segments in polyurethane, so the domain of hard segments is amorphous, while the microcrystals of soft segments dispersed in the polyurethane are affected by the content of hard segments, therefore, the transparency of polyurethane can be tailored by the content of hard segments. It provides a simple design and a feasible preparation method for transparent self-healing polymer.

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