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/anie.202217941
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发表时间：
2023
期刊：
影响因子：
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通讯作者：
Sheiko,SergeiS
中科院分区：
文献类型：
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作者：
Zhang,Daixuan;Vashahi,Foad;Dashtimoghadam,Erfan;Hu,Xiaobo;Wang,ClaireJ;Garcia,Jessica;Bystrova,AleksandraV;Vatankhah-Varnoosfaderani,Mohammad;Leibfarth,FrankA;Sheiko,SergeiS
无法再加工热固性材料阻碍了其实用性和可持续性。理想的材料应结合联合收割机的闭环回收和升级能力。这种特性在聚二甲基硅氧烷瓶刷网络中实现，使用热可逆的Diels-Alder环加成，以实现可逆分解成聚合物熔体和按需重新配置成具有较低或较高刚度的弹性体。通过用受控分数的休眠交联剂和交联剂清除剂（例如呋喃封端的双马来酰亚胺和蒽）分别加载官能化网络来调节交联密度。所得的模量变化精确地遵循活化的呋喃和马来酰亚胺部分的化学计量，表明在再加工期间没有副反应。所提出的环状度概念独立于主链或侧链化学，使其可能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.