Chemical upcycling of end-of-life poly(lactide) plastics to lactide,lactate ester and new poly(lactide)has been achieved by using magnesium bis[bis(trimethylsilyl)amide][Mg(HMDS)_(2)]as promoter.Mg(HMDS)2 showed high ...Chemical upcycling of end-of-life poly(lactide) plastics to lactide,lactate ester and new poly(lactide)has been achieved by using magnesium bis[bis(trimethylsilyl)amide][Mg(HMDS)_(2)]as promoter.Mg(HMDS)2 showed high efficiency in L-lactide polymerization and poly(lactide) depolymerization.Mg(HMDS)_(2)/Ph_(2) CHOH catalytic system displayed high ring-opening selectivity and the characteristic of immortal polymerization.Taking advantage of transesterification,depolymerizations of end-oflife poly(lactide) plastics to lactate ester (polymer to value-added chemicals) and lactide (polymer to monomer) were achieved with high yields.Besides,a new“depolymerization-repolymerization”strategy was proposed to directly transform poly(lactide) into new poly(lactide).This work provides a theoretical basis for the design of polymerization and depolymerization catalysts and promotes the development of degradable polymers.展开更多
Chemical recycling to monomer(CRM)represents a crucial approach to achieving the circular plastic economy.This study systematically investigates the design principles of a highly efficient and selective depolymerizati...Chemical recycling to monomer(CRM)represents a crucial approach to achieving the circular plastic economy.This study systematically investigates the design principles of a highly efficient and selective depolymerization system for the closed-loop recycling of poly(L-lactic acid)(PLLA)to its monomer,L-lactide(L-LA).Using commercially available diethyl zinc(ZnEt_(2))as the catalyst in synergy with acetonitrile(MeCN)as the solvent,the system achieves high depolymerization activity while suppressing the formation of meso-lactide.Further mechanistic studies reveal that this catalytic system promotes rapid transesterification,which is key to its exceptional performance.The scalability and reusability of the system have also been further validated.Meanwhile,the easy post-treatment characteristics of the catalytic system have also been considered,ensuring high yield and purity of the recovered L-LA monomer.This work will provide theoretical support for the design of a CRM depolymerization system for polyester materials.展开更多
Plastics are integral to numerous significant social advancements.Nonetheless,their contribution to environmental pollution and climate crises cannot be disregarded,as their negative impact on the environment increase...Plastics are integral to numerous significant social advancements.Nonetheless,their contribution to environmental pollution and climate crises cannot be disregarded,as their negative impact on the environment increases with incremental production capacity and demand.Concerted global action is urgently required to promote the green recycle of plastics to prevent their accumulation in the environment and mitigate carbon emissions.This review aims to reveal the paths of green development for polyester plastics,incorporating the trends of the green revolution in mature commercial polyester plastics,newly emerging biodegradable polyester plastics,and future polyester plastics.A critical discussion was conducted on the current and potential future research areas from multiple perspectives,including raw materials,processes,and recycling,to propel us into a future marked by sustainability.展开更多
Epoxy resin thermosets(ERTs)are indispensable materials in daily life,particularly in composites,construction,transportation,and aviation.The highly cross-linked frameworks in cured ERTs provide excellent durability a...Epoxy resin thermosets(ERTs)are indispensable materials in daily life,particularly in composites,construction,transportation,and aviation.The highly cross-linked frameworks in cured ERTs provide excellent durability and stability.However,their chemical inertness,which is a double-edged sword,poses significant recycling challenges,thereby threatening the environment[1].In addition,the raw material for ERTs,fossil-based bisphenol A(BPA),has potential adverse health effects on humans.The critical challenge is to develop suitable ERT candidates that are both renewable at the source and recyclable at the end.It requires ingenious structure and molecular design to simultaneously entrust polymer materials with excellent performances.展开更多
基金support by the National Natural Science Foundation of China (No. 21901249)Taishan Scholars Program of Shandong Province (No. tsqn201812112)the Scientific Research and Innovation Fund Project of Shandong Energy Research Institute (No. SEI I202004)。
文摘Chemical upcycling of end-of-life poly(lactide) plastics to lactide,lactate ester and new poly(lactide)has been achieved by using magnesium bis[bis(trimethylsilyl)amide][Mg(HMDS)_(2)]as promoter.Mg(HMDS)2 showed high efficiency in L-lactide polymerization and poly(lactide) depolymerization.Mg(HMDS)_(2)/Ph_(2) CHOH catalytic system displayed high ring-opening selectivity and the characteristic of immortal polymerization.Taking advantage of transesterification,depolymerizations of end-oflife poly(lactide) plastics to lactate ester (polymer to value-added chemicals) and lactide (polymer to monomer) were achieved with high yields.Besides,a new“depolymerization-repolymerization”strategy was proposed to directly transform poly(lactide) into new poly(lactide).This work provides a theoretical basis for the design of polymerization and depolymerization catalysts and promotes the development of degradable polymers.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA0540300)the General Program of the National Natural Science Foundation of China(22571312)+2 种基金the Taishan Scholars Program of Shandong Province(tstp20240520)the Major Science and Technology Innovation Program of Shandong Province(2022CXGC020604)the Natural Science Foundation of Shandong Province(ZR2023ME008)。
文摘Chemical recycling to monomer(CRM)represents a crucial approach to achieving the circular plastic economy.This study systematically investigates the design principles of a highly efficient and selective depolymerization system for the closed-loop recycling of poly(L-lactic acid)(PLLA)to its monomer,L-lactide(L-LA).Using commercially available diethyl zinc(ZnEt_(2))as the catalyst in synergy with acetonitrile(MeCN)as the solvent,the system achieves high depolymerization activity while suppressing the formation of meso-lactide.Further mechanistic studies reveal that this catalytic system promotes rapid transesterification,which is key to its exceptional performance.The scalability and reusability of the system have also been further validated.Meanwhile,the easy post-treatment characteristics of the catalytic system have also been considered,ensuring high yield and purity of the recovered L-LA monomer.This work will provide theoretical support for the design of a CRM depolymerization system for polyester materials.
基金support by the National Natural Science Foundation of China(21901249)the Taishan Scholars Program of Shandong Province(tsqn201812112)the Scientific Research and Innovation Fund Project of the Shandong Energy Research Institute(SEI I202004).
文摘Plastics are integral to numerous significant social advancements.Nonetheless,their contribution to environmental pollution and climate crises cannot be disregarded,as their negative impact on the environment increases with incremental production capacity and demand.Concerted global action is urgently required to promote the green recycle of plastics to prevent their accumulation in the environment and mitigate carbon emissions.This review aims to reveal the paths of green development for polyester plastics,incorporating the trends of the green revolution in mature commercial polyester plastics,newly emerging biodegradable polyester plastics,and future polyester plastics.A critical discussion was conducted on the current and potential future research areas from multiple perspectives,including raw materials,processes,and recycling,to propel us into a future marked by sustainability.
基金supported by the Natural Science Foundation of Shandong Province(ZR2023ME008)the Major Science and Technology Innovation Program of Shandong Province(2022CXGC020604).
文摘Epoxy resin thermosets(ERTs)are indispensable materials in daily life,particularly in composites,construction,transportation,and aviation.The highly cross-linked frameworks in cured ERTs provide excellent durability and stability.However,their chemical inertness,which is a double-edged sword,poses significant recycling challenges,thereby threatening the environment[1].In addition,the raw material for ERTs,fossil-based bisphenol A(BPA),has potential adverse health effects on humans.The critical challenge is to develop suitable ERT candidates that are both renewable at the source and recyclable at the end.It requires ingenious structure and molecular design to simultaneously entrust polymer materials with excellent performances.
