Imine based covalent adaptable networks from diacetone acrylamide polymerization

The construction of covalent adaptable networks (CANs) without the need for post-modification, complex monomer synthesis routes, or expensive materials is highly desirable for the practical application of dynamic covalent chemistry. In the present study, the commercially available acrylate monomer, diacetone acrylamide (DAAM), was initially polymerized using a traditional radical polymerization method. Subsequently, it was cross-linked with amine agents under hot-processing conditions to form aliphatic imine-based CANs. The resulting materials exhibited glass transition temperatures (T _g ) in the range of 95 to 107°C, good thermal stability, mechanical and thermomechanical properties. All samples were amenable to mechanical recycling. Post-recycling, both the tensile strength and Young's Modulus exhibited a slight deterioration, retaining approximately 80% of their original properties. The results from gel content analysis and structural characterization of both pristine and recycled samples indicate that the observed reduction in mechanical properties and T _g (approximately 70°C) can be attributed to a decrease in the degree of cross-linking and the release of aliphatic ketone groups. Furthermore, all samples demonstrated degradability under acidic conditions, attributable to their aliphatic imine structure. By using this facile approach to prepare acrylate-based imine CANs, we establish an important framework for polymer materials that are both reprocessable and biodegradable.