In this study,a new class of biodegradable contraceptive implants was prepared via the UV irradiation molding method,among which,progestin levonorgestrel(LNG)was used as a model drug.Photo-cross-linked aliphatic polyc...In this study,a new class of biodegradable contraceptive implants was prepared via the UV irradiation molding method,among which,progestin levonorgestrel(LNG)was used as a model drug.Photo-cross-linked aliphatic polycarbonates(APCs),namely,poly(trimethylene carbonate-co-2,2′-dimethyltrimethylene carbonate)[P(TMC-co-DTC)]elastomers,were used as the drug delivery matrix.The results obtained from the degradation experiments carried out in Sprague-Dawley(SD)rats showed that the cross-linked elastomer had the degradation characteristics of the surface erosion degradation mechanism,with no generation of acid degradation products,and excellent form-stability,which met the performance requirements of the matrix for a long-acting sustained-release delivery system.The in vitro cytotoxicity tests and histological and immunohistochemical evaluations showed good biocompatibility and biosafety of the elastomer matrix material and contraceptive implants.Subsequently,the implant formulations were screened by in vitro release experiments,and their release kinetics were explored.Finally,in the evaluation study of the in vivo anti-fertility effect,the implants exhibited excellent dimensional stability and were degraded by a surface erosion mechanism.LNG achieved a stable and sustained release in female SD rats,maintaining a long-acting contraceptive duration of up to 4 months.The contraceptive implants obtained in this study could be used to address the limitations of currently available formulations,which required secondary surgical removal and a single means of regulating drug release kinetics.Therefore,these implants could provide a new option for birth control needs and may be of significance in reducing the incidence of induced abortion and protecting female fertility.展开更多
The chemical reversion of polymers via ring-closing depolymerization(RCD)to their monomeric constituents is a highly promising avenue to enable end-of-life recycling and reuse.However,most reported systems using RCD r...The chemical reversion of polymers via ring-closing depolymerization(RCD)to their monomeric constituents is a highly promising avenue to enable end-of-life recycling and reuse.However,most reported systems using RCD revolve around bespoke monomer designs to facilitate facile depolymerization,and there exists relatively few investigations into the influence of functional groups on the ability of a particular monomer to cleanly undergo depolymerization.Here,we perform computational investigations into the energy barriers for RCD of 6-membered aliphatic carbonates in different solvents.The results corroborate trends observed in prior experimental studies,validating the utility of computational investigations towards understanding RCD.Experimental evaluation of the thermal depolymerization in two of the studied polycarbonates confirmed their ability to undergo RCD.Overall,this work highlights the advantage of high-throughput energy barrier computations to provide meaningful insight into broad reactivity trends that would be highly laborious to access experimentally.展开更多
Aliphatic polyesters and polycarbonates are among the promising sustainable polymers,which exhibit unique degradability and chain-chain interactions owing to their heterofunctionality.However,monocomponent aliphatic p...Aliphatic polyesters and polycarbonates are among the promising sustainable polymers,which exhibit unique degradability and chain-chain interactions owing to their heterofunctionality.However,monocomponent aliphatic polyesters and polycarbonates usually suffer from inferior properties and functionalities.By contrast,precisely modulated block copolymers composed of polyesters and polycarbonates give rise to sustainable materials with tailored performance.An efficient approach to synthesize the block copolymers is the ring-opening(co)polymerization of the heterocycle monomers.Herein,this review presents the heterocycle monomer ring-opening(co)polymerization for the formation of sequence-controlled block polyesters and polycarbonates.Available synthetic strategies,different monomers,monomer combinations and the catalyst systems for the formation of different block polyesters and polycarbonates are summarized.展开更多
The master curves of a series of aliphatic polycarbonates （APCs） with different lengths of methylene segments in the repeat unit were obtained by dynamic rheological measurements. The plateau modulus and entanglemen...The master curves of a series of aliphatic polycarbonates （APCs） with different lengths of methylene segments in the repeat unit were obtained by dynamic rheological measurements. The plateau modulus and entanglement molecular weight were determined and cross-checked by different methods. Though having distinct difference in chemical structure of repeat units, both APCs and bisphenol-A polycarbonates have the similar entanglement weight and entanglement spacing. On the other side, the plateau modulus decreases with increasing the length of the side group of aliphatic polycarbonates with different side-chain lengths in the literature. The packing length model can explain the relationship between chain structure and entanglements.展开更多
A new degradable aliphatic poly(butylene-co-e-caprolactone carbonate)(PBCL)was synthesized through the terpolymerization of carbon dioxide,1,2-butylene oxide(BO)and e-caprolactone(CL),a polymer supported bimetallic co...A new degradable aliphatic poly(butylene-co-e-caprolactone carbonate)(PBCL)was synthesized through the terpolymerization of carbon dioxide,1,2-butylene oxide(BO)and e-caprolactone(CL),a polymer supported bimetallic complex(PBM)was used as a catalyst.The terpolymers prepared were characterized by FT-IR,1H NMR,13C NMR,WXRD and DSC.The hydrolysis tests were carried out to appraise the degradability of the copolymers.展开更多
In this paper the miscibility of poly (ε-caprolactone) (PCL) and aliphatic polycarbonate (APC) is studied by using DSC. The results show that PCL and APC are miscible in all ranges of composition. The interaction par...In this paper the miscibility of poly (ε-caprolactone) (PCL) and aliphatic polycarbonate (APC) is studied by using DSC. The results show that PCL and APC are miscible in all ranges of composition. The interaction parameter between the polymers is calculated from the melting point depression data. Using optical microscope, the shapes of the PCL spherulites in the blends are observed.展开更多
A new cyclic carbonate,2,2-ethylenedioxypropane-1,3-diol carbonate(EOPDC),was synthesized through a two-step reaction from dihydroxyacetone dimer,and polymerized in bulk initiated by Sn(Oct)2 to give a high molecular ...A new cyclic carbonate,2,2-ethylenedioxypropane-1,3-diol carbonate(EOPDC),was synthesized through a two-step reaction from dihydroxyacetone dimer,and polymerized in bulk initiated by Sn(Oct)2 to give a high molecular weight polycarbonate.The structure of monomer and the polymer were characterized by FT-IR,1H NMR,13C NMR.The cytotoxicity of the obtained polycarbonate was investigated by MTT assay.展开更多
CO2-copolymer based polyurethane foams were synthesized and characterized in this paper. The foams were found to have higher strength and lower heat of combustion than the conventional polyether polyurethane foams. ...CO2-copolymer based polyurethane foams were synthesized and characterized in this paper. The foams were found to have higher strength and lower heat of combustion than the conventional polyether polyurethane foams. They may find wide applications in many fields.展开更多
Reuse/recycling of expensive components in next-generation optoelectronic systems(e.g.,flexible electronics and foldable displays)for sustainability purposes impose stringent requirements on optically clear adhesive(O...Reuse/recycling of expensive components in next-generation optoelectronic systems(e.g.,flexible electronics and foldable displays)for sustainability purposes impose stringent requirements on optically clear adhesive(OCA)with on-demand adhesion/deadhesion capability.Although some hot-melt OCAs have been developed,there still remain great challenges in balancing the mechanical property,adhesion/detachment and recyclability/reusability of the OCAs.Herein,we developed a debondable and robust polyurethane(PU)-based optically clear adhesive with both mechanical and chemical recyclability,overcoming the critical bottlenecks in sustainable advanced manufacturing.The ductile yet strong PU-based OCAs not only can adhere to various optically transparent glass and polymeric substrates(with a bonding strength high up to 5.0 MPa),but also exhibit deadhesion capability at high temperature owing to the thermally sensitive H-bonding interaction within the polymer network.The ondemand adhesion/deadhesion facilitates non-destructive detachment of functional assemblies and materials recycling/repair.The mechanical and chemical recyclability of PU-based OCAs can also effectively reduce the cost and address the endof-life issues.Moreover,the PU-based OCAs outperformed some commercial optical adhesives.In view of the straightforward synthesis,easy industrial scale-up and exceptional comprehensive properties,the PU-based OCAs will provide promising transformative solutions for advancing the circular economy and sustainability in next-generation optoelectronic devices.展开更多
Zinc(Zn)alloys have demonstrated significant potential in healing critical-sized bone defects.However,the clinical application of Zn alloys implants is still hindered by challenges including excessive release of zinc ...Zinc(Zn)alloys have demonstrated significant potential in healing critical-sized bone defects.However,the clinical application of Zn alloys implants is still hindered by challenges including excessive release of zinc ions(Zn^(2+)),particularly in the early stage of implantation,and absence of bio-functions related to complex bone repair processes.Herein,a biodegradable aliphatic polycarbonate drug-eluting coating was fabricated on zinc-lithium(Zn-Li)alloys to inhibit Zn^(2+)release and enhance the osteogenesis,angiogenesis,and bacteriostasis of Zn alloys.Specifically,the photo-curable aliphatic polycarbonates were co-assembled with simvastatin and deposited onto Zn alloys to produce a drug-loaded coating,which was crosslinked by subsequent UV light irradiation.During the 60 days long-term immersion test,the coating showed distinguished stable drug release and Zn^(2+)release inhibition properties.Benefiting from the regulated release of Zn^(2+)and simvastatin,the coating facilitated the adhesion,proliferation,and differentiation of MC3T3-E1 cells,as well as the migration and tube formation of EA.hy926 cells.Astonishingly,the coating also showed remarkable antibacterial properties against both S.aureus and E.coli.The in vivo rabbit critical-size femur bone defects model demonstrated that the drug-eluting coating could efficiently promote new bone formation and the expression of platelet endothelial cell adhesion molecule-1(CD31)and osteocalcin(OCN).The enhancement of osteogenesis,angiogenesis,and bacteriostasis is achieved by precisely controlling of the released Zn^(2+)at an appropriate level,as well as the stable release profile of simvastatin.This tailored aliphatic polycarbonate drug-eluting coating provides significant potential for clinical applications of Zn alloys implants.展开更多
Iridium(Ir(Ⅲ))complex are appealing candidates for photocatalytic chemistry and photodynamic therapy for their superior photoredox properties.However,their clinical applications are hampered by the high dark toxicity...Iridium(Ir(Ⅲ))complex are appealing candidates for photocatalytic chemistry and photodynamic therapy for their superior photoredox properties.However,their clinical applications are hampered by the high dark toxicity,poor water solubility and faint absorption in near-infrared(NIR)region.To overcome these limitations,herein,a biodegradable aliphatic polycarbonate-Ir(Ⅲ)complex(PC-Ir)was synthesized by binding bis(cyclometalated)(pna)_(4)Ir_(2)^(2+)fragments(pna,6-phenylnicotinaldehyde)to terpyridine ligands in the pendant of polycarbonate.The obtained PC-Ir exhibits two-photon absorption capability and presents strong ROS generation capacity via typeⅠand typeⅡmechanism with coenzyme nicotinamide adenine dinucleotide(NADH)as electron donors upon irradiation with 660 nm laser.Furthermore,PC-Ir could directly activate phenylboronic acid caged Doxorubicin prodrug(Dox-PBA)under normoxia and hypoxia conditions to release potent Dox.In vitro and in vivo data confirmed the highly efficient photodynamic therapy of PC-Ir NPs and synergetic photoactivated chemotherapy against 4T1 breast cancer.Overall,this work presents a promising strategy to construct Ir(Ⅲ)-based polymeric photosensitizer with two-photon excitation and less oxygen dependent mechanism,which can also serve as a carrier for combination anticancer therapy.展开更多
基金sponsored by the Natural Science Foundation of Liaoning Province(Nos.2022-YGJC-69,2021-BS-110)the support program for excellent young scholars of China Medical University.
文摘In this study,a new class of biodegradable contraceptive implants was prepared via the UV irradiation molding method,among which,progestin levonorgestrel(LNG)was used as a model drug.Photo-cross-linked aliphatic polycarbonates(APCs),namely,poly(trimethylene carbonate-co-2,2′-dimethyltrimethylene carbonate)[P(TMC-co-DTC)]elastomers,were used as the drug delivery matrix.The results obtained from the degradation experiments carried out in Sprague-Dawley(SD)rats showed that the cross-linked elastomer had the degradation characteristics of the surface erosion degradation mechanism,with no generation of acid degradation products,and excellent form-stability,which met the performance requirements of the matrix for a long-acting sustained-release delivery system.The in vitro cytotoxicity tests and histological and immunohistochemical evaluations showed good biocompatibility and biosafety of the elastomer matrix material and contraceptive implants.Subsequently,the implant formulations were screened by in vitro release experiments,and their release kinetics were explored.Finally,in the evaluation study of the in vivo anti-fertility effect,the implants exhibited excellent dimensional stability and were degraded by a surface erosion mechanism.LNG achieved a stable and sustained release in female SD rats,maintaining a long-acting contraceptive duration of up to 4 months.The contraceptive implants obtained in this study could be used to address the limitations of currently available formulations,which required secondary surgical removal and a single means of regulating drug release kinetics.Therefore,these implants could provide a new option for birth control needs and may be of significance in reducing the incidence of induced abortion and protecting female fertility.
文摘The chemical reversion of polymers via ring-closing depolymerization(RCD)to their monomeric constituents is a highly promising avenue to enable end-of-life recycling and reuse.However,most reported systems using RCD revolve around bespoke monomer designs to facilitate facile depolymerization,and there exists relatively few investigations into the influence of functional groups on the ability of a particular monomer to cleanly undergo depolymerization.Here,we perform computational investigations into the energy barriers for RCD of 6-membered aliphatic carbonates in different solvents.The results corroborate trends observed in prior experimental studies,validating the utility of computational investigations towards understanding RCD.Experimental evaluation of the thermal depolymerization in two of the studied polycarbonates confirmed their ability to undergo RCD.Overall,this work highlights the advantage of high-throughput energy barrier computations to provide meaningful insight into broad reactivity trends that would be highly laborious to access experimentally.
基金supported by the National Natural Science Foundation of China,Fund for Distinguished Young Scholars(No.52325301)CAS Project for Young Scientists in Basic Research(YSBR-094)the National Natural Science Foundation of China,Basic Science Center Program(No.51988102).
文摘Aliphatic polyesters and polycarbonates are among the promising sustainable polymers,which exhibit unique degradability and chain-chain interactions owing to their heterofunctionality.However,monocomponent aliphatic polyesters and polycarbonates usually suffer from inferior properties and functionalities.By contrast,precisely modulated block copolymers composed of polyesters and polycarbonates give rise to sustainable materials with tailored performance.An efficient approach to synthesize the block copolymers is the ring-opening(co)polymerization of the heterocycle monomers.Herein,this review presents the heterocycle monomer ring-opening(co)polymerization for the formation of sequence-controlled block polyesters and polycarbonates.Available synthetic strategies,different monomers,monomer combinations and the catalyst systems for the formation of different block polyesters and polycarbonates are summarized.
基金financially supported by National Natural Science Foundation of China(No.20874109)National High Technology Research and Development Program of China(No.2009AA033601) and the Chinese Academy of Sciences
文摘The master curves of a series of aliphatic polycarbonates （APCs） with different lengths of methylene segments in the repeat unit were obtained by dynamic rheological measurements. The plateau modulus and entanglement molecular weight were determined and cross-checked by different methods. Though having distinct difference in chemical structure of repeat units, both APCs and bisphenol-A polycarbonates have the similar entanglement weight and entanglement spacing. On the other side, the plateau modulus decreases with increasing the length of the side group of aliphatic polycarbonates with different side-chain lengths in the literature. The packing length model can explain the relationship between chain structure and entanglements.
文摘A new degradable aliphatic poly(butylene-co-e-caprolactone carbonate)(PBCL)was synthesized through the terpolymerization of carbon dioxide,1,2-butylene oxide(BO)and e-caprolactone(CL),a polymer supported bimetallic complex(PBM)was used as a catalyst.The terpolymers prepared were characterized by FT-IR,1H NMR,13C NMR,WXRD and DSC.The hydrolysis tests were carried out to appraise the degradability of the copolymers.
基金The subject supported by National Natural Science Foundation of China
文摘In this paper the miscibility of poly (ε-caprolactone) (PCL) and aliphatic polycarbonate (APC) is studied by using DSC. The results show that PCL and APC are miscible in all ranges of composition. The interaction parameter between the polymers is calculated from the melting point depression data. Using optical microscope, the shapes of the PCL spherulites in the blends are observed.
基金supported by The National Key Basic Research Program of China(G1999064703).
文摘A new cyclic carbonate,2,2-ethylenedioxypropane-1,3-diol carbonate(EOPDC),was synthesized through a two-step reaction from dihydroxyacetone dimer,and polymerized in bulk initiated by Sn(Oct)2 to give a high molecular weight polycarbonate.The structure of monomer and the polymer were characterized by FT-IR,1H NMR,13C NMR.The cytotoxicity of the obtained polycarbonate was investigated by MTT assay.
基金This project was supported by the National Natural Science Foundation of China(No.20274053).
文摘CO2-copolymer based polyurethane foams were synthesized and characterized in this paper. The foams were found to have higher strength and lower heat of combustion than the conventional polyether polyurethane foams. They may find wide applications in many fields.
基金supported by the National Natural Science Foundation of China(52222302)。
文摘Reuse/recycling of expensive components in next-generation optoelectronic systems(e.g.,flexible electronics and foldable displays)for sustainability purposes impose stringent requirements on optically clear adhesive(OCA)with on-demand adhesion/deadhesion capability.Although some hot-melt OCAs have been developed,there still remain great challenges in balancing the mechanical property,adhesion/detachment and recyclability/reusability of the OCAs.Herein,we developed a debondable and robust polyurethane(PU)-based optically clear adhesive with both mechanical and chemical recyclability,overcoming the critical bottlenecks in sustainable advanced manufacturing.The ductile yet strong PU-based OCAs not only can adhere to various optically transparent glass and polymeric substrates(with a bonding strength high up to 5.0 MPa),but also exhibit deadhesion capability at high temperature owing to the thermally sensitive H-bonding interaction within the polymer network.The ondemand adhesion/deadhesion facilitates non-destructive detachment of functional assemblies and materials recycling/repair.The mechanical and chemical recyclability of PU-based OCAs can also effectively reduce the cost and address the endof-life issues.Moreover,the PU-based OCAs outperformed some commercial optical adhesives.In view of the straightforward synthesis,easy industrial scale-up and exceptional comprehensive properties,the PU-based OCAs will provide promising transformative solutions for advancing the circular economy and sustainability in next-generation optoelectronic devices.
基金support for this work from the National Natural Science Foundation of China,China (52173127).
文摘Zinc(Zn)alloys have demonstrated significant potential in healing critical-sized bone defects.However,the clinical application of Zn alloys implants is still hindered by challenges including excessive release of zinc ions(Zn^(2+)),particularly in the early stage of implantation,and absence of bio-functions related to complex bone repair processes.Herein,a biodegradable aliphatic polycarbonate drug-eluting coating was fabricated on zinc-lithium(Zn-Li)alloys to inhibit Zn^(2+)release and enhance the osteogenesis,angiogenesis,and bacteriostasis of Zn alloys.Specifically,the photo-curable aliphatic polycarbonates were co-assembled with simvastatin and deposited onto Zn alloys to produce a drug-loaded coating,which was crosslinked by subsequent UV light irradiation.During the 60 days long-term immersion test,the coating showed distinguished stable drug release and Zn^(2+)release inhibition properties.Benefiting from the regulated release of Zn^(2+)and simvastatin,the coating facilitated the adhesion,proliferation,and differentiation of MC3T3-E1 cells,as well as the migration and tube formation of EA.hy926 cells.Astonishingly,the coating also showed remarkable antibacterial properties against both S.aureus and E.coli.The in vivo rabbit critical-size femur bone defects model demonstrated that the drug-eluting coating could efficiently promote new bone formation and the expression of platelet endothelial cell adhesion molecule-1(CD31)and osteocalcin(OCN).The enhancement of osteogenesis,angiogenesis,and bacteriostasis is achieved by precisely controlling of the released Zn^(2+)at an appropriate level,as well as the stable release profile of simvastatin.This tailored aliphatic polycarbonate drug-eluting coating provides significant potential for clinical applications of Zn alloys implants.
基金supported by the Natural Science Foundation of Hebei Province(No.B2022202029)the Government Guide the Development of Local Science and Technology Special Funds(No.226Z1203G).
文摘Iridium(Ir(Ⅲ))complex are appealing candidates for photocatalytic chemistry and photodynamic therapy for their superior photoredox properties.However,their clinical applications are hampered by the high dark toxicity,poor water solubility and faint absorption in near-infrared(NIR)region.To overcome these limitations,herein,a biodegradable aliphatic polycarbonate-Ir(Ⅲ)complex(PC-Ir)was synthesized by binding bis(cyclometalated)(pna)_(4)Ir_(2)^(2+)fragments(pna,6-phenylnicotinaldehyde)to terpyridine ligands in the pendant of polycarbonate.The obtained PC-Ir exhibits two-photon absorption capability and presents strong ROS generation capacity via typeⅠand typeⅡmechanism with coenzyme nicotinamide adenine dinucleotide(NADH)as electron donors upon irradiation with 660 nm laser.Furthermore,PC-Ir could directly activate phenylboronic acid caged Doxorubicin prodrug(Dox-PBA)under normoxia and hypoxia conditions to release potent Dox.In vitro and in vivo data confirmed the highly efficient photodynamic therapy of PC-Ir NPs and synergetic photoactivated chemotherapy against 4T1 breast cancer.Overall,this work presents a promising strategy to construct Ir(Ⅲ)-based polymeric photosensitizer with two-photon excitation and less oxygen dependent mechanism,which can also serve as a carrier for combination anticancer therapy.
