New Kind of Thermoplastic Polyurea Elastomers Synthesized from CO2 and with Self-Healing Properties

To convert CO 2 into valuable polymers is of great significance from the viewpoints of environmental and sustainable development, as polymers are among the most widely produced chemicals in the world greatly affecting human life. Herein, a kind of functional polymers, CO 2 -based polyureas, were successfully synthesized via condensation of CO 2 with alicyclic isophoronediamine (IPDA) and linear trioxa-1,13-tridecanediamine (TTD). The synthesized CO 2 -based polyurea shows not only self-healing capabilities but also excellent mechanical properties. It is self-healable at room temperature and the superior mechanical properties of the tensile strength (6.6 MPa) and toughness (28.7 MJ m –3 ) can be recovered to 95%. These unexpected properties were demonstrated to result from the rich and varied hydrogen bonds in the polyurea molecular chain between urea moieties originating from alicyclic IPDA and linear TTD. The strength, arrangement, and density of the hydrogen bonds are controllable by adjusting the amount of IPDA and TTD, and thus the mechanical and self-healing properties can be optimized. Furthermore, the synthesized novel CO 2 -based polyureas exhibit excellent properties in the surface protection and energy absorption, and so we believe they will have potential applications in a wide field.