Affiliation:
1. Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry and Materials Science Northwest University 710069 Xi'an P. R. China
2. School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative Molecules Shanghai Jiao Tong University 200240 Shanghai P. R. China
3. Key Laboratory of Medicinal Molecule Science and Pharmaceutics Engineering Ministry of Industry and Information Technology School of Chemistry and Chemical Engineering Beijing Institute of Technology 100081 Beijing P. R. China
Abstract
AbstractFoldamer is a scaled‐down version of coil spring, which can absorb and release energy by conformational change. Here, polymer networks with high density of molecular springs were developed by employing anion‐coordination‐based foldamers as the monomer. The coiling of the foldamer is controlled by oligo(urea) ligands coordinating to chloride ions; subsequently, the folding and unfolding of foldamer conformations endow the polymer network with excellent energy dissipation and toughness. The mechanical performance of the corresponding polymer networks shows a dramatic increase from P‐L2UCl (non‐folding), to P‐L4UCl (a full turn), and then to P‐L6UCl (1.5 turns), in terms of strength (2.62 MPa; 14.26 MPa; 22.93 MPa), elongation at break (70 %; 325 %; 352 %), Young's modulus (2.69 MPa; 63.61 MPa; 141.50 MPa), and toughness (1.12 MJ/m3; 21.39 MJ/m3; 49.62 MJ/m3), respectively, which is also better than those without anion centers and the non‐foldamer based counterparts. Moreover, P‐L6UCl shows enhanced strength and toughness than most of the molecular‐spring based polymer networks. Thus, an effective strategy for designing high‐performance anion‐coordination‐based materials is presented.
Funder
National Natural Science Foundation of China