Circular Upcycling of Bottlebrush Thermosets
Circular Upcycling of Bottlebrush Thermosets
复制标题
洗瓶刷热固性材料的循环升级
DOI：
10.1002/ange.202217941
复制
发表时间：
2023
影响因子：
--
通讯作者：
Sheiko, Sergei S.
中科院分区：
文献类型：
--
作者：
Zhang, Daixuan;Vashahi, Foad;Dashtimoghadam, Erfan;Hu, Xiaobo;Wang, Claire J.;Garcia, Jessica;Bystrova, Aleksandra V.;Vatankhah‐Varnoosfaderani, Mohammad;Leibfarth, Frank A.;Sheiko, Sergei S.
不能再加工热固性材料阻碍了它们的实用性和可持续性。理想的材料应该结合闭环回收和升级回收的能力。这种特性是在聚二甲基硅氧烷瓶刷网络中实现的，使用热可逆的diols - alder环添加物，既可以可逆地分解成聚合物熔体，也可以按需重新配置成刚度更高或更低的弹性体。通过在功能化网络中分别加入一定量的休眠交联剂和交联清除剂（如呋喃封头的双马来酰亚胺和蒽）来调节交联密度。由此产生的模量变化精确地遵循活性呋喃和马来酰亚胺部分的化学计量，表明在后处理过程中缺乏副反应。所提出的圆形概念是独立于主链或侧链化学，使其潜在地适用于广泛的刷状聚合物。
The inability to re‐process thermosets hinders their utility and sustainability. An ideal material should combine closed‐loop recycling and upcycling capabilities. This trait is realized in polydimethylsiloxane bottlebrush networks using thermoreversible Diels–Alder cycloadditions to enable both reversible disassembly into a polymer melt and on‐demand reconfiguration to an elastomer of either lower or higher stiffness. The crosslink density was tuned by loading the functionalized networks with a controlled fraction of dormant crosslinkers and crosslinker scavengers, such as furan‐capped bis‐maleimide and anthracene, respectively. The resulting modulus variations precisely followed the stoichiometry of activated furan and maleimide moieties, demonstrating the lack of side reactions during reprocessing. The presented circularity concept is independent from the backbone or side chain chemistry, making it potentially applicable to a wide range of brush‐like polymers.