Precision Macromolecular Chemistry, Université de Strasbourg, CNRS, Institut Charles Sadron UPR22, 23 rue du Loess, 67034, Strasbourg Cedex 2, France.
Aix Marseille Université, CNRS, UMR 7273, Institut of Radical Chemistry, 13397, Marseille Cedex 20, France.
Angew Chem Int Ed Engl. 2020 Nov 9;59(46):20390-20393. doi: 10.1002/anie.202008864. Epub 2020 Sep 15.
The degradation and repair of uniform sequence-defined poly(N-substituted urethane)s was studied. Polymers containing an ω-OH end-group and only ethyl carbamate main-chain repeat units rapidly degrade in NaOH solution through an ω→α depolymerization mechanism with no apparent sign of random chain cleavage. The degradation mechanism is not notably affected by the nature of the side-chain N-substituents and took place for all studied sequences. On the other hand, depolymerization is significantly influenced by the molecular structure of the main-chain repeat units. For instance, hexyl carbamate main-chain motifs block unzipping and can therefore be used to control the degradation of specific sequence sections. Interestingly, the partially degraded polymers can also be repaired; for example by using a combination of N,N'-disuccinimidyl carbonate with a secondary amine building-block. Overall, these findings open up interesting new avenues for chain-healing and sequence editing.
本文研究了均一序列定义的聚（取代氨酯）的降解和修复。含有ω-OH 端基和仅乙基碳酸酯主链重复单元的聚合物在 NaOH 溶液中通过 ω→α 解聚机制迅速降解，没有明显的随机链断裂迹象。降解机制不受侧链 N-取代基的性质显著影响，并且发生在所有研究的序列中。另一方面，解聚明显受到主链重复单元的分子结构的影响。例如，己基碳酸酯主链基序阻止解拉链，因此可用于控制特定序列部分的降解。有趣的是，部分降解的聚合物也可以修复；例如，使用 N,N'-二琥珀酰亚胺碳酸酯与仲胺砌块的组合。总的来说，这些发现为链修复和序列编辑开辟了有趣的新途径。
