Two kinds of 1,4-anhydroribose derivatives,1,4-anhydro-2,3-O-benzylidene-T-D-ribopyranose(ABRP)and 1,4-anhydro-2,3-O-isopropylidene-T-D-ribopyranose(AIRP)were prepared fromD-ribose.The ringopening copolymerizations of...Two kinds of 1,4-anhydroribose derivatives,1,4-anhydro-2,3-O-benzylidene-T-D-ribopyranose(ABRP)and 1,4-anhydro-2,3-O-isopropylidene-T-D-ribopyranose(AIRP)were prepared fromD-ribose.The ringopening copolymerizations of ABRP and AIRP in various feed ratios were carried out with SbCl_5 and BF_3OEt_2 as catalyst at low temperatures.The copolymer structure was characterized by means of ^(1)H,^(13)C NMR spectroscopy and specific rotation.When SbCl_(5)was used as catalyst,the copolymer obtained had completely 1,4-β-pyranosidic structure,i.e.,cellulosetype structure.However,when BF_(3)OEt_2 was used as catalyst,the copolymer had a mixed structure of furanosidic and pyranosidic units.展开更多
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
文摘Two kinds of 1,4-anhydroribose derivatives,1,4-anhydro-2,3-O-benzylidene-T-D-ribopyranose(ABRP)and 1,4-anhydro-2,3-O-isopropylidene-T-D-ribopyranose(AIRP)were prepared fromD-ribose.The ringopening copolymerizations of ABRP and AIRP in various feed ratios were carried out with SbCl_5 and BF_3OEt_2 as catalyst at low temperatures.The copolymer structure was characterized by means of ^(1)H,^(13)C NMR spectroscopy and specific rotation.When SbCl_(5)was used as catalyst,the copolymer obtained had completely 1,4-β-pyranosidic structure,i.e.,cellulosetype structure.However,when BF_(3)OEt_2 was used as catalyst,the copolymer had a mixed structure of furanosidic and pyranosidic units.
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.
