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The Magic of Organocatalytic Synergism in Switchable Polymerization:One-pot Synthesis of Block Copolymers with Programmable Sequences and Compositions
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作者 Shuai-Shuai Zhu Mao-Ji Zhao +1 位作者 Ying-Jie Yuan Yong Wang 《Chinese Journal of Polymer Science》 2026年第1期68-78,I0010,共12页
Switchable polymerization is emerging as a powerful tool to construct block copolymers directly from mixtures of monomers.However,current achievements typically iterate between two polymerization cycles to afford prod... Switchable polymerization is emerging as a powerful tool to construct block copolymers directly from mixtures of monomers.However,current achievements typically iterate between two polymerization cycles to afford products with fixed sequences and compositions.Herein,we report the triethylborane/1,8-diazabicyclo[5.4.0]undec-7-ene(Et_3B/DBU)pair-mediated four-component switchable polymerization of propylene oxide(PO),CO_(2),phthalic anhydride(PA),and racemic lactide(rac-LA),which enables the on-demand synthesis of four different block copolymers,i.e.,poly(propylene phthalate)-b-polylactide(PPE-b-PLA),PPE-b-PLA-b-poly(propylene carbonate)(PPC),PPE-b-PPC-b-PLA,and PPE-b-PPCb-poly(propylene oxide)(PPO),through rationally modulating the Lewis pair(LP)ratio.Core to this protocol is that increasing the loading of Et_(3)B accelerates the ring-opening of PO while impeding the reactivity of rac-LA,thus allowing for fine-tuning of the thermodynamic and kinetic of the switchable polymerization.Therefore,the four polymerization cycles involving PO/PA ring-opening copolymerization(ROCOP),PO/CO_(2) ROCOP,rac-LA ring-opening polymerization(ROP),and PO ROP can be connected and discriminated in precisely programmed manners. 展开更多
关键词 Switchable polymerization Organic Lewis pair Block copolymers ring-opening copolymerization Multicomponent reaction
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Wide bandgap steric carbazole-fluorene-nanogrid polymers via metal-free C-N polymerization for deep-blue polymer light-emitting diodes
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作者 Man Xu Qianyi Li +8 位作者 Jingyao Ma Hao Li Yunfei Zhu Fan Yu Kuande Wang Tao Zhou Quanyou Feng Linghai Xie Jinyi Lin 《Chinese Chemical Letters》 2026年第1期356-360,共5页
To precisely control intrachain π-electron delocalization and interchain interaction simultaneously is the prerequisite to obtain stable and efficient deep-blue light-emitting p-n polymer semiconductors for the polym... To precisely control intrachain π-electron delocalization and interchain interaction simultaneously is the prerequisite to obtain stable and efficient deep-blue light-emitting p-n polymer semiconductors for the polymer light-emitting diodes(PLEDs).Herein,we introduced the steric carbazole-fluorene nanogrid into light-emitting diphenyl sulfone-based p-n polymer semiconductors(PG and PDG) via metal-free C-N coupling polymerization for the fabrication of deep-blue PLEDs.The steric,rigid and twisted configuration between nanogrid and diphenyl sulfone in PG and PDG present the unique characteristic of large steric hindrance interaction to suppress interchain aggregation in solid state.Due to the different length of electron-deficient diphenyl sulfone monomers,PG showed a deep-blue emission with a maximum peak at 428 nm but red-shifted to 480 nm for the PDG films.Interestingly,similar deep-blue emission behavior of PG in diluted non-polar solution and films suggested the extremely weak interchain aggregation.Finally,PLEDs based on PG are fabricated with a stable deep-blue emission of CIE(0.15,0.10),and corresponding EL spectral profile is also completely identical to PL ones of diluted solution,revealed the intrachain emission without obvious interchain excited state,confirmed effectiveness of the steric hindrance functionalization of nanogrid in p-n polymer semiconductor for deep-blue light-emitting organic optoelectronics. 展开更多
关键词 p-n polymer semiconductors Metal-free C-N polymerization Steric carbazole-fluorene nanogrid Diphenyl sulfone Deep-blue polymer light-emitting diodes
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Oligomeric α-diimine nickel catalysts for enhanced ethylene polymerization
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作者 Jingfeng Yue Zhenxin Tang +1 位作者 Yuxing Zhang Zhongbao Jian 《Chinese Chemical Letters》 2026年第1期380-384,共5页
Catalysts are key for olefin polymerization reactions and are also ubiquitous in catalysis science.Multinuclear metal catalysts have witnessed enhanced performances in catalytic reactions relative to mononuclear catal... Catalysts are key for olefin polymerization reactions and are also ubiquitous in catalysis science.Multinuclear metal catalysts have witnessed enhanced performances in catalytic reactions relative to mononuclear catalysts,but which substantially involve multi-step,tedious,and difficult synthesis.Herein,this study reports an intriguing approach to construct multi-nuclear catalysts for the milestoneα-diimine nickel catalysts using an oligomeric strategy.A polymerizable norbornene unit is incorporated into theα-diimine ligand backbone,leading to the formation of the monomeric nickel catalyst Ni_(1)and its corresponding oligomeric nickel catalysts(Ni_(3)and Ni_(5))with varying degrees of polymerization(DP=3 and 5).Notably,the oligomeric catalyst Ni_(5)was facilely scaled up(50 g-level),showed enhanced thermal stability,exhibited 4.6 times higher activity,and yielded polyethylene elastomer with a 379%increased molecular weight in ethylene polymerization,compared to the monomeric catalyst Ni_(1).Catalytic performance enhancements of oligomeric catalysts were found to be DP-dependent.The kilogram-scale polyethylene,produced using Ni_(5)in a 20 L reactor,presented a highly branched all-hydrocarbon structure,which demonstrated typical elastic properties(tensile strength:4 MPa,elastic recovery:SR=72%)along with great processability(MFI=3.0 g/10 min),insulating characteristics(volume resistivity=2×10^(16)Ω/m),and hydrophobicity(water vapor permeability:0.03 g/m^(2)/day),suggesting potentially practical applications. 展开更多
关键词 POLYOLEFIN Oligomeric catalyst Polyethylene elastomer Ethylene polymerization Nickel catalyst
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Ring-opening Polymerization of Benzo-fused Thiolactones toward Chemically Recyclable Semi-aromatic Polythioesters
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作者 Wei Xiong Kun Li +3 位作者 Long-Hai Liu Si-Qi Wang Zhong-Zheng Cai Jian-Bo Zhu 《Chinese Journal of Polymer Science》 2025年第6期973-980,I0009,共9页
Chemically recyclable polythioesters are of particular interest owing to their unique properties and desired sustainability.By the exploit of a benzo-fusion strategy toε-thiocaprolactone,we successfully improved the ... Chemically recyclable polythioesters are of particular interest owing to their unique properties and desired sustainability.By the exploit of a benzo-fusion strategy toε-thiocaprolactone,we successfully improved the chemical recyclability and regulated the thermal and mechanical properties of the resulting polythioesters.The efficient ring-opening polymerization(ROP)of benzo-fused thiolactone monomers(M)containing different substituents gave rise to high-molecular-weight semi-aromatic polythioesters P(M)s.The resulting P(M)s showcased tunable physical and mechanical properties.The debenzylation of P(M3)was able to generate P(M3-OH)with free hydroxyl sidechains.Notably,chemical recycling of the resulting P(M)s back to their corresponding monomers via bulk thermal depolymerization achieved high efficiency(>95%yield,99%purity),establishing a closed-loop lifecycle. 展开更多
关键词 Polythioesters Chemical recyclability ring-opening polymerization Sustainable polymers Monomer design
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Cyclic ethers-based solid electrolyte derived from in situ ring-opening polymerization strategy
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作者 Wubin Du Yong Wu +7 位作者 Hao Cheng Ran Bu Kang Shen Yuanzhong Tan Zhijun Wu Hongge Pan Yifan Wang Yingying Lu 《Green Energy & Environment》 2025年第7期1359-1376,共18页
Although solid-state polymer electrolytes(SPEs)are expected to solve the safety hazards and limited energy density in the energy storage systems,they still encounter an inferior electrode/electrolyte interface when pr... Although solid-state polymer electrolytes(SPEs)are expected to solve the safety hazards and limited energy density in the energy storage systems,they still encounter an inferior electrode/electrolyte interface when prepared in an ex situ manner.Recently,in situ polymerization of SPEs favor high interfacial infiltrability,improved interface contact,and reduced interface resistance,owing to the formation of a"superconformal"interface between electrode and electrolyte.Especially,in situ strategies employing ring-opening polymerization(ROP)are emerging as dazzling stars,further enabling moderate polymerization conditions,controllable molecular structure,and reduced interfacial side reaction.As the main monomers that can be in situ polymerized via the ROP strategy,cyclic ethers have been used to construct the CE-SPEs with many merits,including good battery electrochemical performances and a simple assembly process.Here,as a systematic summarization of the existing reports,this review focuses on the polymerization mechanism of ROP,the design principles of CE-SPEs electrolytes,and the recent application of in situ CE-SPEs.In particular,this review thoroughly discusses the selection of different cyclic monomers,initiators and various modification approaches in in situ fabricating CE-SPEs.Ending with offering future challenges and perspectives,this review envisions shedding light on the profound understanding and scientific guidance for further development of high-performance in situ CE-SPEs. 展开更多
关键词 Cyclic ethers Solid-state polymer electrolytes ring-opening polymerization In situ polymerization
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Zn(TFSI)_(2)-Mediated Ring-Opening Polymerization for Electrolyte Engineering Toward Stable Aqueous Zinc Metal Batteries
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作者 Zhenjie Liu Murong Xi +6 位作者 Rui Sheng Yudai Huang Juan Ding Zhouliang Tan Jiapei Li Wenjun Zhang Yonggang Wang 《Nano-Micro Letters》 2025年第5期479-491,共13页
Practical Zn metal batteries have been hindered by several challenges,including Zn dendrite growth,undesirable side reactions,and unstable electrode/electrolyte interface.These issues are particularly more serious in ... Practical Zn metal batteries have been hindered by several challenges,including Zn dendrite growth,undesirable side reactions,and unstable electrode/electrolyte interface.These issues are particularly more serious in low-concentration electrolytes.Herein,we design a Zn salt-mediated electrolyte with in situ ring-opening polymerization of the small molecule organic solvent.The Zn(TFSI)_(2)salt catalyzes the ring-opening polymerization of(1,3-dioxolane(DOL)),generating oxidation-resistant and non-combustible long-chain polymer(poly(1,3-dioxolane)(pDOL)).The pDOL reduces the active H_(2)O molecules in electrolyte and assists in forming stable organic–inorganic gradient solid electrolyte interphase with rich organic constituents,ZnO and ZnF_(2).The introduction of pDOL endows the electrolyte with several advantages:excellent Zn dendrite inhibition,improved corrosion resistance,widened electrochemical window(2.6 V),and enhanced low-temperature performance(freezing point=-34.9°C).Zn plating/stripping in pDOL-enhanced electrolyte lasts for 4200 cycles at 99.02%Coulomb efficiency and maintains a lifetime of 8200 h.Moreover,Zn metal anodes deliver stable cycling for 2500 h with a high Zn utilization of 60%.A Zn//VO_(2)pouch cell assembled with lean electrolyte(electrolyte/capacity(E/C=41 mL(Ah)^(-1))also demonstrates a capacity retention ratio of 92%after 600 cycles.These results highlight the promising application prospects of practical Zn metal batteries enabled by the Zn(TFSI)2-mediated electrolyte engineering. 展开更多
关键词 Electrolyte engineering ring-opening polymerization Lewis acid catalyst Zn metal battery
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Ring-opening Metathesis Polymerization to Access Degradable Iminebased Polymers
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作者 Wu Li Si-Jia Cheng +2 位作者 You-Gui Li Muhammad Asadullah Khan Min Chen 《Chinese Journal of Polymer Science》 2025年第6期908-913,I0006,共7页
As a powerful synthetic tool,ruthenium-catalyzed ring-opening metathesis polymerization(ROMP)has been widely utilized to prepare diverse heteroatom-containing polymers.In this contribution,we report the synthesis of t... As a powerful synthetic tool,ruthenium-catalyzed ring-opening metathesis polymerization(ROMP)has been widely utilized to prepare diverse heteroatom-containing polymers.In this contribution,we report the synthesis of the novel imine-based polymer through the copolymerization of cyclooctene with cyclic imine comonomer via ROMP.Because of the efficient hydrolysis reactions of the imine group,the generated copolymer can be easily degraded under mild condition.Moreover,the generated degradable product was the telechelic polymer bearing amine group,which was highly challenged for its direct synthesis.And this telechelic polymer could also be used for the further synthesis of new polymer through post-transformation.The introduction of imine unit in this work provides a new example of the degradable polymer synthesis. 展开更多
关键词 Degradable polymer ring-opening metathesis polymerization Imine-based polymer COpolymerization
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Mechanochromic Branched Polyethylenes Synthesized through Ring-opening Metathesis Terpolymerization
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作者 Yan-Lin Zong Yi-Xin Zhang Zhong-Bao Jian 《Chinese Journal of Polymer Science》 2025年第7期1181-1189,共9页
Mechanochromic polyolefins represent a novel class of functionalized polyolefins,which still remains significant challenges.Pd(II)-catalyzed coordination-insertion copolymerization is a feasible method for achieving t... Mechanochromic polyolefins represent a novel class of functionalized polyolefins,which still remains significant challenges.Pd(II)-catalyzed coordination-insertion copolymerization is a feasible method for achieving this kind of polymers,yet with linear microstructures.Ringopening metathesis polymerization(ROMP)offers another promising avenue for affording functionalized polyolefins.This method exhibits high polar group tolerance and the ability to precisely regulate polymer branches.In this study,we report the method for producing mechanochromic branched polyethylenes via ROMP.By employing the terpolymerization of a well-designed monomer containing the mechanochromic group,NB-ABF,with cyclooctene(COE)and long-chain 5-hexylcyclooctene(COE-C6),following by hydrogenation process,we synthesized a range of functionalized branched polyethylenes characterized by varied branching density and polar monomer incorporation.These polymers bear a structural resemblance to functionalized ethylene-octene copolymers.After crosslinking,mechanochromophores are generated,and mechanochromism is achieved in uniaxial tensile testing.A comprehensive assessment reveals that both the incorporation of polar monomers and variations in branching density significantly influence their mechanical properties.Notably,upon stretching,these materials display pronounced visible color change,confirming the successful development of mechanochromic branched polyethylenes. 展开更多
关键词 ring-opening metathesis polymerization POLYOLEFIN Functionalized branched polyethylene Mechanochromism
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Recent progress of heterocycle ring-opening(co)polymerization for the synthesis of sequence-controlled block polyesters and polycarbonates
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作者 Hongyu Zhao Chenyang Hu +1 位作者 Xuan Pang Xuesi Chen 《Smart Molecules》 2025年第4期1-19,共19页
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
关键词 aliphatic polycarbonates aliphatic polyesters block copolymers heterocycle monomers ring-opening(co)polymerization
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Histidine N-Thiocarboxyanhydride:Direct Synthesis and Polymerization without Protection towards Well-defined Polyhistidine 被引量:1
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作者 Song-Yi Xu Tian-Wen Bai +2 位作者 Bo-Tuo Zheng Ze-Hua Li Jun Ling 《Chinese Journal of Polymer Science》 2025年第8期1311-1319,共9页
Consisting of natural histidine residues,polyhistidine(PHis)simulates functional proteins.Traditional approaches towards PHis require the protection of imidazole groups before monomer synthesis and polymerization to p... Consisting of natural histidine residues,polyhistidine(PHis)simulates functional proteins.Traditional approaches towards PHis require the protection of imidazole groups before monomer synthesis and polymerization to prevent degradation and side reactions.In the contribution,histidine N-thiocarboxyanhydride(His-NTA)is directly synthesized in aqueous solution without protection.With the self-catalysis of the imidazole side group,the ring-closing reaction to form His-NTA does not require any activating reagent(e.g.,phosphorus tribromide),which is elucidated by density functional theory(DFT)calculations.His-NTA directly polymerizes into PHis bearing unprotected imidazole groups with designable molecular weights(4.2-7.7 kg/mol)and low dispersities(1.10-1.19).Kinetic experiments and Monte Carlo simulations reveal the elementary reactions and the relationship between the conversion of His-NTA and time during polymerization.Block copolymerization of His-NTA with sarcosine N-thiocarboxyanhydride(Sar-NTA)demonstrate versatile construction of functional polypept(o)ides.The triblock copoly(amino acid)PHis-b-PSar-b-PHis is capable to reversibly coordinate with transition metal ions(Fe^(2+),Co^(2+),Ni^(2+),Cu^(2+)and Zn^(2+))to form pH-sensitive hydrogels. 展开更多
关键词 N-thiocarboxyanhydride Polyhistidine Controlled ring-opening polymerization POLYPEPTIDE Poly(amino acid)s
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Enolic Schiff Base Zinc Amide Complexes: Highly Active Catalysts for Ring-Opening Polymerization of Lactide and ε-Caprolactone 被引量:3
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作者 Chen-Yang Hu Ran-Long Duan +5 位作者 Jing-Wei Yang Shu-Jun Dong Zhi-Qiang Sun Xuan Pang Xian-Hong Wang Xue-Si Chen 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2018年第10期1123-1128,共6页
A series of zinc silylamido complexes based upon NNO tridentate enolic Schiff base framework have been synthesized and characterized. These complexes were tested for the ring opening polymerization of lactide and e-ca... A series of zinc silylamido complexes based upon NNO tridentate enolic Schiff base framework have been synthesized and characterized. These complexes were tested for the ring opening polymerization of lactide and e-caprolactone, exhibiting notably high activity at ambient temperature, The influence of imine bridge length and substituents of diketone over the course of polymerization was investigated in details. Remarkably, 4a was confirmed to be a rare example of exceedingly active and robust zinc catalysts, achieving major transformation of lactide under extremely low loading (0.025 mol%) within 18 rain. The influence of various monomers as well as the polymerization mechanism have also been discussed. 展开更多
关键词 ZINC Β-DIKETONE ring-opening polymerization LACTIDE Ε-CAPROLACTONE
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RING-OPENING POLYMERIZATION OF TRIMETHYLENE CARBONATE CATALYZED BY NOVEL SINGLE COMPONENT RARE EARTH CALIXARENE COMPLEXES 被引量:3
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作者 沈之荃 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2005年第4期407-410,共4页
In this paper,ring-opening polymerization of trimethylene carbonate(TMC)with rare earth(Nd,Y,La)ρ-tert- butylcalix[n]arene(n=4,6,and 8)complexes as catalysts has been studied.Poly(trimethylene carbonate)(PTMC)with M_... In this paper,ring-opening polymerization of trimethylene carbonate(TMC)with rare earth(Nd,Y,La)ρ-tert- butylcalix[n]arene(n=4,6,and 8)complexes as catalysts has been studied.Poly(trimethylene carbonate)(PTMC)with M_v of 21,400 was produced by bulk polymerization under the conditions as follows:[TMC]_0/[Nd](molar ratio)=1000,80℃, 8 h.Mechanism study reveals that the polymerization proceeds via a coordination mechanism. 展开更多
关键词 ring-opening polymerization Trimethylene carbonate CALIXARENE Rare earth complex
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Ring-opening Polymerization ofε-Caprolactone Using Lanthanide Tris(4-tert-butylphenolate)s as a Single-component Initiator 被引量:4
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作者 Cui Ping YU, Li Fang ZHANG, Zhi Quan SHEN Institute of Polymer Science, Zhejiang University, Hangzhou 310027 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第10期1021-1023,共3页
The ring-opening polymerization of e-caprolactone (CL) initiated by novel single lanthanide tris(4-tert-butylphenolate)s [Ln(OTBP)3] is reported. Single-component La(OTBP)3 can effectively prepare polycaprolactone (PC... The ring-opening polymerization of e-caprolactone (CL) initiated by novel single lanthanide tris(4-tert-butylphenolate)s [Ln(OTBP)3] is reported. Single-component La(OTBP)3 can effectively prepare polycaprolactone (PCL) with over 90% yield and viscosity average molecular weight about 60 x 10 under quite mild conditions: molar ratio of CL to initiator is 1000, 60 C, 2 h in toluene. Mechanism study indicates that the monomer inserts into the growing chain via the break of acyl-oxygen bond of CL. 展开更多
关键词 Lanthanide tris(4-tert-butylphenolate)s e-caprolactone ring-opening polymerization.
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Bimetallic Aluminum Complexes Supported by Bis(salicylaldimine) Ligand: Synthesis, Characterization and Ring-opening Polymerization of Lactide 被引量:2
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作者 Tong Shi Quan-De Zheng +2 位作者 Wei-Wei Zuo Shao-Feng Liu Zhi-Bo Li 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2018年第2期149-156,共8页
Two types of bifunctional bis(salicylaldimine) ligands(syn-L and anti-L) were designed and synthesized to support bimetallic aluminum complexes. Owing to the rigid anthracene skeleton, syn-L and anti-L successfull... Two types of bifunctional bis(salicylaldimine) ligands(syn-L and anti-L) were designed and synthesized to support bimetallic aluminum complexes. Owing to the rigid anthracene skeleton, syn-L and anti-L successfully locked two Al centers in close proximity(syn-Al2) and far apart(anti-Al2), respectively. The distance between two Al centers in syn-Al2 was defined by X-ray diffraction as 6.665 ?, which is far shorter than that in anti-Al2. In the presence of stoichiometrical Bn OH, syn-Al2 and anti-Al2 were both efficient for ring-opening polymerization(ROP) of rac-LA with the former being more active. In the presence of excess Bn OH, syn-Al2 showed an efficient and immortal feature, consistent with high conversions, matched Mns, narrow molecular weight distributions and end group fidelity, while anti-Al2 had a much lower activity or even became entirely inactive due to rapid decomposition, indicated by in situ ~1H-NMR experiments of Al complexes with Bn OH. 展开更多
关键词 Bimetallic catalyst Aluminum complex ring-opening polymerization Immortal polymerization POLYESTER
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Stereoselective Ring-opening Polymerization of rac-Lactide by Bulky Chiral and Achiral N-heterocyclic Carbenes 被引量:2
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作者 Hui Li Bai-Ru Ai Miao Hong 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2018年第2期231-236,共6页
Despite the extraordinary success has been achieved in metal catalyst-promoted stereoselective ring-opening polymerization(ROP) of rac-lactide(rac-LA), well-controlled stereoselective rac-LA ROP by organic catalys... Despite the extraordinary success has been achieved in metal catalyst-promoted stereoselective ring-opening polymerization(ROP) of rac-lactide(rac-LA), well-controlled stereoselective rac-LA ROP by organic catalyst still remains a scientific challenge. Here we report our investigations into organocatalytic stereoselective ROP of rac-LA by utilizing novel bulky chiral and achiral N-heterocyclic carbenes(NHC), 1,3-bis-(1′-naphthylethyl)imidazolin-2-ylidene. The effect of polymerization conditions(e.g. solvent, temperature, alcohol initiator) on ROP behavior by these bulky NHCs has been fully studied, leading to the formation of isotactic-rich stereoblock polylactide(Pi = 0.81) under optimized conditions with high activity(Conv. = 98% in 30 min) and narrow molecular weight dispersity(D = 1.05). 展开更多
关键词 POLYLACTIDE ring-opening polymerization STEREOSELECTIVITY Organic catalyst N-heterocyclic carbene
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Ring-opening Polymerization of 2-Oxabicyclo[2.2.2]octan-3-one and the Influence of Stereochemistry on the Thermal Properties of the Polyesters 被引量:2
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作者 Tong Zhou Yu-Ting Guo +1 位作者 Fu-Sheng Du Zi-Chen Li 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2022年第10期1173-1182,I0008,共11页
Polyesters with cyclic structures in the main chain typically possess superior mechanical and thermal properties together with chemical recyclability.Ring-opening polymerization(ROP)of bridged or fused bicyclic lacton... Polyesters with cyclic structures in the main chain typically possess superior mechanical and thermal properties together with chemical recyclability.Ring-opening polymerization(ROP)of bridged or fused bicyclic lactones is a simple,and in most cases controlled method to synthesize polyesters with alicyclic moieties in the polymer backbone.The stereochemistry of the alicyclic structures has a great effect on the polymer properties,which can be regulated by varying the polymerization conditions.Here,we report a systematic investigation on the ROP of 2-oxabicyclo[2.2.2]octan-3-one([2.2.2]VL)under different conditions.When initiated byn-butyl lithium(n-BuLi)or catalyzed by trifluoromethanesulfonic acid(TfOH)in the presence of benzyl alcohol,P[2.2.2]VLs containing all cis^(-1),4 disubstituted cyclohexane ring were obtained.However,P[2.2.2]VLs initiated by sodium methoxide(MeONa)or catalyzed by organic superbase contained both cis and trans isomeric structural units.The cis to trans transformation mechanism under these conditions was manifested,and the effect of stereochemical variations on the properties ofP[2.2.2]VLwas revealed.The stereoregularP[2.2.2]VLs,bothcisandtrans,exhibited higher crystallinity and melting temperatures(Tm)than those of the stereoirregular isomers.Finally,the degradation of P[2.2.2]VL with acid at high temperature could recover 3-cyclohexenecarboxylic acid. 展开更多
关键词 2-Oxabicyclo[2.2.2]octan-3-one ring-opening polymerization STEREOCHEMISTRY Polyester Thermal properties
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Preparation of Degradable Polymenthide and Its Elastomers from Biobased Menthide via Organocatalyzed Ring-opening Polymerization and UV Curing 被引量:2
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作者 Na Zhao Xin-Xin Cao +1 位作者 Jin-Feng Shi Zhi-Bo Li 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2020年第10期1092-1098,I0006,共8页
Development of degradable polyester elastomers plays an important role in the applications of soft mateirals.Noncrystalline polymenthides(PMs)from menthol derived lactone monomers are excellent soft segments for prepa... Development of degradable polyester elastomers plays an important role in the applications of soft mateirals.Noncrystalline polymenthides(PMs)from menthol derived lactone monomers are excellent soft segments for preparing degradable polyester elastomers.By using cyclic trimeric phosphazene base(CTPB)as an organocatalyst,we succesfully synthesized PMs with different molecular weights(8.2 kDa to 100.7 kDa)in high yields via ring-opening polymerization(ROP)of menthide.When a CTPB/urea binary catalytic system was adopted,the polymerizations proceeded in a more controlled manner.Using glycerol as initiator,star shaped PMs with well.defined structure were synthesized and subsequently end-capped by acrylate.UV iradiation of the terminal acrylate groups in the star-shaped PMs resulted in formation of chemically cos-linked polyester elastomers without heat or other stimuli.The obtained polyester elastomers exhibit matched modulus(3.8-5.5 MPa),tensile strength(0.56-0.68 MPa),and strain at break(280%-320%)with soft body tssues,displaying great potential in biomedical applications. 展开更多
关键词 Polyester elastomer Cyclic trimeric phosphazene base ring-opening polymerization Menthide Biobased polyester
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RING-OPENING POLYMERIZATION OFε-CAPROLACTONE USING LANTHANIDE TRIS(N-PHENYL-3,5-DI-T-BUTYLSALICYLALDIMINATO)S AS SINGLE COMPONENT CATALYST 被引量:2
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作者 沈之荃 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2007年第5期541-544,共4页
Ring-opening polymerization of ε-caprolactone has been carried out by using rare earth Schiff base complexes: lanthanide tris(N-phenyl-3,5-di-t-butylsalicylaldiminato)s [Ln(OPBS)3] as single component catalyst f... Ring-opening polymerization of ε-caprolactone has been carried out by using rare earth Schiff base complexes: lanthanide tris(N-phenyl-3,5-di-t-butylsalicylaldiminato)s [Ln(OPBS)3] as single component catalyst for the first time. The influences of different rare earth elements, monomer and catalyst concentration as well as reaction time on the polymerization were investigated. Mechanism studies showed that monomer inserts into the active site with the acyl-oxygen bond scission rather than the break of alkyl-oxygen bond. 展开更多
关键词 ring-opening polymerization Ε-CAPROLACTONE Lanthanide Schiff base complex.
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SYNTHESIS, CHARACTERIZATION AND RING-OPENING POLYMERIZATION OF CYCLIC (ARYLENE PHOSPHONATE) OLIGOMERS 被引量:2
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作者 陈天禄 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2004年第1期83-89,共7页
A series of cyclic (arylene phosphonate) oligomers were prepared by reaction of phenylphosphonic dichloride (PPD) with various bisphenols under pseudo-high dilution conditions via interfacial polycondensation. The yie... A series of cyclic (arylene phosphonate) oligomers were prepared by reaction of phenylphosphonic dichloride (PPD) with various bisphenols under pseudo-high dilution conditions via interfacial polycondensation. The yield of cyclic (arylene phosphonate) oligomers is over 85% by using hexadecyltrimethylammoniun bromide as phase transfer catalyst (PTC) at 0 'C . The structures of the cyclic oligomers were confirmed by a combination of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and IR analysis. These cyclic oligomers undergo facile ring-opening polymerization in the melt by using potassium 4,4'-biphenoxide as the initiator to give linear polyphosphonate. Free-radical ring-opening polymerization of cyclic(arylene phosphonate) oligomers containing sulfur linkages was also performed in the melt using 2,2'-dithiobis(benzothiazole) (DTB) as the initiator at 270 °C and the resulting polymer had a Mw, of 8 × 103 with a molecular weight distribution of 4. Ring-opening copolymerization of these cyclic oligomers with cyclic carbonate oligomers was also achieved. The average molecular weight of the resulting copolymer is higher than the corresponding homopolymer and the thermal stability of the copolymer is better than the corresponding homopolymer. 展开更多
关键词 Cyclic(arylene phosphonate) oligomer ring-opening polymerization COpolymer
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Readily Prepared and Tunable Ionic Organocatalysts for Ring-opening Polymerization of Lactones 被引量:3
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作者 Zhuo-Lun Jiang Jun-Peng Zhao Guang-Zhao Zhang 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2019年第12期1205-1214,I0005,共11页
Highly potent ionic organocatalyst is developed for room-temperature controlled ring-opening polymerization(ROP)of lactones,includingδ-valerolactone,ε-caprolactone,andδ-hexalactone.The catalysts are prepared by sim... Highly potent ionic organocatalyst is developed for room-temperature controlled ring-opening polymerization(ROP)of lactones,includingδ-valerolactone,ε-caprolactone,andδ-hexalactone.The catalysts are prepared by simply mixing tetra-n-butyl ammonium hydroxide and a(thio)urea at elevated temperature under vacuum,and used in cooperation with an alcoholic initiator.The performance of the catalyst is readily adjusted and optimized through variation of the(thio)urea precursor,catalyst composition,and reaction condition.Urea-derived catalysts are generally superior to thiourea-derived ones.Provided with proper N-substituents,the catalyst affords both high polymerization efficiency and high selectivity for monomer enchainment over macromolecular transesterification,even at high monomer conversion and/or substantially extended reaction time.In addition to acidity,structural symmetry of the urea also proves decisive for the catalytic activity,which enables a catalyst-assisted proton transfer process for the ring-opening of lactone and thus provides a novel mechanistic insight for ROP catalyzed by hydrogen-bonding type bifunctional ionic organocatalysts. 展开更多
关键词 Organocatalytic polymerization ring-openING polymerization POLYESTER
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