Azomethine‐Containing Pyrrolo[3,2‐ b ]pyrrole Copolymers for Simple and Degradable Conjugated Polymers
Azomethine‐Containing Pyrrolo[3,2‐ b ]pyrrole Copolymers for Simple and Degradable Conjugated Polymers
复制标题
甲亚胺—含吡咯并[3,2—b]吡咯共聚物的简单且可降解的共轭聚合物
DOI：
10.1002/marc.202300220
复制
发表时间：
2023
影响因子：
4.6
通讯作者：
Collier, Graham S.
中科院分区：
文献类型：
--
作者：
Bartlett, Kimberley A.;Charland‐Martin, Ariane;Lawton, Jonathan;Tomlinson, Aimée L.;Collier, Graham S.
共轭聚合物作为无机半导体的潜在轻质和高度可定制的替代品受到了极大的关注，但它们的合成通常很复杂，产生有毒副产物，并且它们通常不是设计为可降解或可回收的。这些缺点需要专门的努力来发现具有能够实现共轭聚合物的靶向和有效降解的设计基序的材料。在这种情况下，利用1，4-二氢吡咯并[3，2-B]吡咯（DHPP）的合成简单性，通过良性酸催化缩聚方案获得含甲亚胺的共聚物。聚合涉及使用对甲苯磺酸作为催化剂使二醛官能化的二氢吡咯并吡咯与作为共聚单体的对苯二胺反应。甲亚胺键的固有动态平衡随后使聚合物在酸存在下在溶液中降解。通过NMR、紫外维斯吸收和荧光光谱监测聚合物的降解，结果表明聚合物可完全降解。值得注意的是，虽然吸光度测量揭示了随着延长暴露于酸而向更高能量的持续转变，但荧光测量显示降解后荧光响应的显著增加。这项研究的结果鼓励环保聚合的持续发展，以获得具有有用特性的聚合物材料，同时创造具有结构手柄的聚合物，用于寿命终止管理或/和可回收性。
Conjugated polymers have received significant attention as potentially lightweight and highly tailorable alternatives to inorganic semiconductors, but their synthesis is often complex, produces toxic byproducts, and they are not typically designed to be degradable or recyclable. These drawbacks necessitate dedicated efforts to discover materials with design motifs that enable targeted and efficient degradation of conjugated polymers. In this vein, the synthetic simplicity of 1,4‐dihydropyrrolo[3,2‐b]pyrroles (DHPPs) is exploited to access azomethine‐containing copolymers via a benign acid‐catalyzed polycondensation protocol. Polymerizations involve reacting a dialdehyde‐functionalized dihydropyrrolopyrrole withp‐phenylenediamine as the comonomer usingp‐toluenesulfonic acid as a catalyst. The inherent dynamic equilibrium of the azomethine bonds subsequently enabled the degradation of the polymers in solution in the presence of acid. Degradation of the polymers is monitored via NMR, UV‐vis absorbance, and fluorescence spectroscopies, and the polymers are shown to be fully degradable. Notably, while absorbance measurements reveal a continued shift to higher energies with extended exposure to acid, fluorescence measurements show a substantial increase in the fluorescence response upon degradation. Results from this study encourage the continued development of environmentally‐conscious polymerizations to attain polymeric materials with useful properties while simultaneously creating polymers with structural handles for end‐of‐life management or/and recyclability.