Dual Dynamic Network Polymer Reinforced Carbon Nanotube Foam With Rapid Self‐Healing and Reversible Cycling Capabilities

The structural damage of carbon–polymer composites is a significant factor limiting their development and stable application. To solve this problem, polymers with fast self‐healing and recyclability were first obtained by introducing dynamic polymer chain segments in different proportions. When the molar ratio of H‐linked 2‐[[(butylamine)carbonyl]oxy]ethyl ester (PBC) and boric acid ester–linked poly(4‐hydroxymethyl) phenylboronic acid (PBA) is 2:1, the highest mechanical strength (2.9 ± 0.2 MPa) and elongation (700%) of the PBC 2 ‐PBA 1 were achieved. Subsequently, the hydroxylated modified carbon nanotube foams (CNTF) were used as templates, which were filled with PBC 2 ‐PBA 1 via a physical impregnation process to prepare CNTF polymer composites (PBC 2 ‐PBA 1 /CNTF). When the CNTF content is 13.4 wt%, the composite exhibits high tensile strength of 5.5 MPa, 189% higher than the mechanical strength of PBC 2 –PBA 1 . Furthermore, it exhibits the self‐healing properties were by the recovery of tensile strength (100%), thermal conductivity (98.7%), and electrical conductivity (100%) at −20°C~100°C. In addition, the composite materials can be recycled and the reassembled material can restore 100% of its original mechanical properties. Therefore, optimization of molecular structure and modification of phase interfaces are the strategies to produce carbon‐polymer composites with excellent self‐healing and recycling functions.