Closed-loop chemical recycling to monomers offers a promising solution to plastic waste,but it is often incompatible with postpolymerization transformation,a powerful strategy that allows for the modification of polym...Closed-loop chemical recycling to monomers offers a promising solution to plastic waste,but it is often incompatible with postpolymerization transformation,a powerful strategy that allows for the modification of polymer structures to achieve a wide variety of properties.Here,we introduced a multipath closed-loop chemical recycling system using a new seven-membered thionolactone(T1).This thionolactone underwent robust anionic and cationic ROP to yield well-defined polythionoester(PTNE)and polythioester(PTE)on demand.Both polymers exhibited distinct properties and could selectively depolymerize to the same thiolactone,T_(iso).Successful repolymerization demonstrated efficient closedloop recyclability.Importantly,PTNE could be directly transformed into PTE in bulk,showcasing the successful postpolymerization transformation before ultimately recovering the same monomer.As a result,closed-loop“T1–PTNE–T_(iso),”“T1–PTE–T_(iso),”and extended“T1–PTNE–PTE–T_(iso)”chemical recycling systems were established.This work presents a new strategy for designing closed-loop recyclable polymers with diverse structures and properties and highlights the benefits of extending the useful lifetime of recyclable polymers through postpolymerization transformation.展开更多
基金funding support from the Natural Science Foundation of China(grant nos.52322301,22131010,52131305,22271270,and 22071232)the Fundamental Research Funds for the Central Universities,China(grant no.WK3450000009)the University Synergy Innovation Program of Anhui Province,China(grant no.GXXT-2023-035).
文摘Closed-loop chemical recycling to monomers offers a promising solution to plastic waste,but it is often incompatible with postpolymerization transformation,a powerful strategy that allows for the modification of polymer structures to achieve a wide variety of properties.Here,we introduced a multipath closed-loop chemical recycling system using a new seven-membered thionolactone(T1).This thionolactone underwent robust anionic and cationic ROP to yield well-defined polythionoester(PTNE)and polythioester(PTE)on demand.Both polymers exhibited distinct properties and could selectively depolymerize to the same thiolactone,T_(iso).Successful repolymerization demonstrated efficient closedloop recyclability.Importantly,PTNE could be directly transformed into PTE in bulk,showcasing the successful postpolymerization transformation before ultimately recovering the same monomer.As a result,closed-loop“T1–PTNE–T_(iso),”“T1–PTE–T_(iso),”and extended“T1–PTNE–PTE–T_(iso)”chemical recycling systems were established.This work presents a new strategy for designing closed-loop recyclable polymers with diverse structures and properties and highlights the benefits of extending the useful lifetime of recyclable polymers through postpolymerization transformation.
