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Chinese Journal of Polymer Science 2024年第3期42卷 364-372,I0008页

作者： Jia-Shu Ma Zhi-Ning Huang Jia-Hao Li Bang-Ping Jiang Yan-Da Liao Shi-Chen Ji Xing-Can Shen State Key Laboratory for chemistry and molecular engineering of Medicinal Resources Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources(Ministry of Education of China)School of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGuilin 541004China School of Computer Science and engineering&School of Software Guangxi Normal UniversityGuilin 541004China

To better characterize the properties of surface-initiated polymers, simultaneous bulk-and surface-initiated polymerizations are usually carried out by assuming that the properties of the surface-initiated polymers resemble those of the bulk-initiated polymers. Through a Monte Carlo simulation using a heterogeneous stochastic reaction model, it was discovered that the bulk-initiated polymers exhibit a higher molecular weight and a lower dispersity than the corresponding surface-initiated polymers, which indicates that the equivalent assumption is invalid. Furthermore, the molecular weight distributions of the two types of polymers are also different, suggesting different polymerization mechanisms. The results can be simply explained by the heterogeneous distributions of reactants in the system. This study is helpful to better understand surface-initiated polymerization.

关键词： Surface-initiated polymerization Polymer brush Stochastic reaction model Heterogeneous polymerization Simultaneous polymerization

Tailoring the Properties of Polyhydroxyalkanoates from Plastics to Elastomers via Stereoselective Copolymerizations of rac-β-Butyrolactone and β-Propiolactone

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Chinese Journal of chemistry 2024年第9期42卷 963-972页

作者： Haoran Zhang JiaojiaoQin Xiaoyan Tang Beijing National Laboratoryfor molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenterfor Soft Matter Science and EngineeringCollegeof Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

Poly(3-hydroxybutyrate),a crucial member of the large biodegradable polyhydroxyalkanoate family,suffers from its *** enhance its performance,we employed a straightforward approach involving the ring-opening copolymerization of racemic-β-butyrolactone(rac-β-BL)andβ-propiolactone(β-PL)using the syndio-selective amino-alkoxy-bis(phenolate)-yttrium complex as a catalyst,thanks to the excellent ductility of poly(3-hydroxypropionate).Control over the rac-β-BL/β-PL feeding ratios and polymerization time yielded random or block copolymers with tunable thermal and mechanical properties comparable to traditional fossil-based ***,we achieved one-pot synthesis of hard-soft-hard triblock copolymers by exploiting monomers’different copolymerization rates and a bifunctional initiator,thus transforming polyhydroxyalkanoates from hard and tough plastics to soft and ductile thermoplastic elastomers.

关键词： Ring-opening(co-)polymerization Biodegradable polymers Polyhydroxyalkanoates Copolymers Plastics Elastomers

Syntheses of new di-nuclear and tetra-nuclear lanthanide 9-anthracenecarboxylates:Magnetocaloric effect,slow magnetic relaxation and luminescent properties

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Journal of Rare Earths 2024年第6期42卷 1101-1109,I0004页

作者： Xing Liu Ruonan Yang Lu Zhang Jian Zhou Chunmei Huang Huahong Zou Zunhong Xiao Chongqing Key Laboratory of Inorganic Functional Materials College of ChemistryChongqing Normal UniversityChongqing401331China Key Laboratory for the chemistry and molecular engineering of Medicinal Resources(Ministry of Education of China) School of Chemistry and Chemical Engineering of Guangxi Normal UniversityGuilin541004China School of chemistry and Materials Guizhou Normal UniversityGuiyang550025China

Lanthanide complex-based materials with magnetic and luminescent properties have received a great deal of attention,owing to their importantly potential applications in diverse *** this work,the 9-anthracenecarboxylic acid(9-Haca)as bridging ligand was applied in combination with optically activeπ-conjugated 2,4,6-tri(2-pyridyl)-1,3,5-triazine(tptz)to construct a series of new di-nuclear and tetranuclear lanthanide 9-anthracenecarboxylates[La_(2)(9-aca)_(6)(tptz)_(2)(μ-H_(2)O)]·0.25H_(2)O(1),[Ln_(2)(9-aca)_(6)(tptz)_(2)(H_(2)O)_(2)]·0.5AQ·CH_(3)COOH_(2)H_(2)O[Ln=Sm(2a),Eu(2b),Gd(2c),Tb(2d),Dy(2e),Tm(2f);AQ=9,10-anthracenedione]and[Ln_(4)(9-aca)_(10)(tptz)_(2)(CH3COO)2]·H_(2)O[Ln=Eu(3a),Gd(3b),Dy(3c)].1 displays a di-nuclear centrosymmetric moiety[La_(2)(9-aca)_(6)(tptz)_(2)(μ-H_(2)O)]built up from two complex[La(9-aca)_(2)(tptz)]groups bridged by one H_(2)O molecule and two syn-syn-μ2-η1:η1-9-aca-bridging ligands,while 2a-2f are isostructural and co mprise another di-nuclear centrosymmetric moieties[Ln_(2)(9-aca)_(6)(tptz)_(2)(H_(2)O)_(2)]based on two complex[Ln(9-aca)_(2)(tptz)(H_(2)O)]groups connected by two syn-syn-μ2-η1:η1-9-aca-bridging ligands,3a-3c are isostructural and show tetra-nuclear centro symmetric moieties[Ln4(9-aca)10(tptz)2(CH3COO)2]containing three types of coordination modes of *** present compounds offer the only examples of lanthanide 9-anthracenecarboxylates decorated by optically active *** investigations of 2a,2c-2f,and 3b-3c indicate that 3c is typical of slow relaxation of the magnetization,while 2c and 3b show significant magnetocaloric effect(MCE)with the value of-ΔSm of 5.26 J/(kg·K)at 4 K and 15.65 J/(kg·K)at 2 K(ΔH=7 T),*** luminescent properties were also studied and reveal that the characteristic luminescent properties of the 7r-conjugated aromatic ligands are introduced into magnetic lanthanide 9-anthracenecarboxylates,simultaneously exhibiting slow magnetic relaxation(or MCE)and luminescen

关键词： Lanthanide complexes Luminescence Magnetic properties Magnetocaloric effect Slow magnetic relaxation Rare earths

Access to High-molecular-Weight Polyethylenes through High Temperature Ethylene Polymerization Catalysed by Ethylene-Bridged ansa-(3-R-Cyclopentadienyl)(Fluorenyl) Zirconocene Complexes

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Chinese Journal of Polymer Science 2024年第1期42卷 42-51,I0007页

作者： Bo Li Haiyan Ma Jiling Huang Shanghai Key Laboratory of Functional Materials chemistry and Laboratory of Organometallic chemistry School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

A series of C1-symmetric ethylene-bridged ansa-(3-R-cyclopentadienyl)(fluorenyl) metallocene complexes(Zr: 1-5;Hf: 6) have been synthesized, characterized and investigated as catalyst precursors for the high temperature ethylene polymerization. Using methylaluminoxane(MAO) as the cocatalyst, zirconium complexes 1-5 bearing a bulky substituent on the 3-position of the cyclopendienyl ring showed high catalytic activities up to 1.48×10^(7) g PE·mol_(Zr)^(-1)·h^(-1) toward the polymerization of ethylene and afforded polyethylenes with high molecular weights(1.49×10^(5)-6.31×10^(5) g/mol), meanwhile exhibting great thermal stability at high temperatures up to 120 ℃ together with a long catalytic life time up to 2 h. By adopting low Al/Zr ratios, such as 125, polyethylenes with ultra high molecular weights up to 2.86×106 g/mol were obtained. It is worthy of noting that zirconium complexes 1-4 bearing a substituent with an aryl pendant showed temperature-dependent activities, which increased rapidly with the increase of polymerization temperature, thus weak interaction of the pendent aryl group with the cationic active center is proposed to account for the very low activities displayed at low temperatures. In contrast to zirconocene complexes 1-5, hafnocene complex 6 only displayed very low catalytic activities toward the polymerization of ethylene and afforded polyethylenes with molecular weights ten times smaller than those obtained by zirconocene complexes 1-5. Zirconocene complexes 1-5 were also able to catalyse the polymerization of propylene at high temperatures, but only afforded waxes with low molecular weights.

关键词： ansa-Metallocene Ethylene Propylene Polymerization High temperature

Interparticle energy transfer between NaNdF_(4) and NaYbF_(4) in self-assembled nanostructures

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Journal of Rare Earths 2024年第6期42卷 1029-1035,I0001页

作者： Xinyu Chen Haoze Yang Yuyang Gu Chenqing Wen Yishuo Sun Jiaming Ke Wei Feng Department of chemistry and State Key Laboratory of molecular engineering of Polymers Fudan University Shanghai200433China

Forster resonance energy transfer(FRET)is a widely used spectroscopic *** development of donor-acceptor combinations is essential to advance this *** make the energy transfer efficiency independent of the external environment,we explored the potential of constructing donor—acceptor combinations with lanthanide ion-doped nanoparticles(LNPs),in which the 4f electrons of the lanthanide ions are shielded by the 5s and 6p ***-radiative energy transfer between LNPs was demonstrated in self-assembled nanostructures and core-shell structure of LNPs was used to control the distance between donor and acceptor in self-assembled *** emission intensity ratio of donor and acceptor illustrates that the energy transfer efficiency decreases significantly with increasing distance and the effective energy transfer distance is 8.5 nm,showing the potential of using LNPs as donor-acceptor pairs in the construction of distance-dependent energy transfer system.

关键词： Lanthanide nanoparticles Self-assembly Energy transfer Distance Epitaxialgrowth Rare earths

Bridging molecular photosensitizer and catalyst on carbon nanotubes toward enhanced selectivity and durability for CO_(2)photoreduction

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Journal of Environmental Sciences 2024年第6期140卷 157-164页

作者： Xiaofeng Cui Xueting Wang Lijun Zhao Jixin Wang Tingting Kong Yujie Xiong Anhui engineering Research Center of Carbon Neutrality The Key Laboratory of Functional Molecular SolidsMinistry of EducationAnhui Laboratory of Molecular-Based MaterialsCollege of Chemistry and Materials ScienceAnhui Normal UniversityWuhu 241002China School of chemistry and Chemical engineering Anqing Normal UniversityAnqing 246011China School of chemistry and Materials Science University of Science and Technology of ChinaHefei 230026China

Homogenous molecular photocatalysts for CO_(2)reduction,especially metal complex-based photosensitizer-catalyst assemblages,have been attracting extensive research interests due to their efficiency and ***,their low durability and recyclability limit practical *** this work,we immobilized the catalysts of metal terpyridyl complexes and the photosensitizer of[Ru(bpy)3]Cl2onto the surface of carbon nanotubes through covalent bonds and electrostatic interactions,respectively,transforming the homogeneous system into a heterogeneous *** characterizations prove that these metal complexes are well dispersed on CNTs with a high loading(ca.12 wt.%).Photocatalytic measurements reveal that catalytic activity is remarkably enhanced when the molecular catalysts are anchored,which is three times higher than that of homogeneous molecular ***,when the photosensitizer of[Ru(bpy)3]Cl2is immobilized,the side reaction of hydrogen evolution is completely suppressed and the selectivity for CO production reaches 100%,with its durability also significantly *** work provides an effective pathway for constructing heterogeneous photocatalysts based on rational assembly of efficient molecular photosensitizers and catalysts.

关键词： durability selectivity catalyst

Manipulating guest-responsive spin transition to achieve switchable fluorescence in a Hofmann-type framework

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Science China chemistry 2024年第10期67卷 3339-3346页

作者： Xue-Ru Wu Shu-Qi Wu Zhi-Kun Liu Ming-Xing Chen Jun Tao Osamu Sato Hui-Zhong Kou engineering Research Center of Advanced Rare Earth Materials (Ministry of Education) Department of ChemistryTsinghua University Institute for Materials chemistry and engineering & IRCCS Kyushu University Key Laboratory of Cluster Science of Ministry of Education School of Chemistry and Chemical EngineeringLiangxiang CampusBeijing Institute of Technology Analytical Instrumentation Center College of Chemistry and Molecular EngineeringPeking University

The change of fluorescence emission manipulated by spin state transition attracts considerable attention owing to its potential applications in magneto-optical switching ***,we report two two-dimensional（2D） Hofmann-type spin crossover（SCO） metal-organic frameworks（MOFs）[FeⅡ（PNI）2{AgⅠ（CN）2}2]·CHCl3（3Ag·CHCl3） and[FeⅡ（PNI）2{AuⅠ（CN）2}2]·CHCl3（3Au·CHCl3） based on the fluorescent ligand N-（4-pyridylmethyl）-1,8-naphthalimide（PNI）.Both complexes exhibit interesting SCO behaviors switched by guest solvent molecules,namely three-step transitions for the solvated complexes and complete onestep hysteretic SCO for the desolvated ones,verified by temperature-dependent magnetic susceptibility measurements,Mossbauer spectra,structural analyses,and differential scanning calorimetry ***,temperature-dependent fluorescence spectra exhibit double peaks（monomer and excimer emission） with both emission peaks change consistent with the change in SCO properties during the solvent molecule *** this study,we integrated guest-responsive SCO behavior into MOFs to manipulate the multistability of spin state and fluorescence switching,providing a rational strategy for the development of stimuli-responsive multifunctional materials.

关键词： spin crossover fluorescence multifunctional materials metal-organic frameworks Hofmann-type

Solution-processed all-inorganic lead halide perovskite/layered double hydroxides superlattices

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Science China chemistry 2024年第9期67卷 2904-2910页

作者： Deyu Li Mingming Zhang Lulu Wei Shubing Tian Mingze Sun Kang Liu Jixiang Xu Lei Wang Jun Xing Key Laboratory of Eco-chemical engineering Ministry of EducationCollege of Chemistry and Molecular EngineeringQingdao University of Science&TechnologyQingdao 266042China college of Sino-German Science and Technology Qingdao University of Science&TechnologyQingdao 266042China

Quantum wells and superlattices are key building blocks in the semiconductor industry,normally fabricated using epitaxial growth techniques,such as vapor phase epitaxy,metalorganic chemical vapor deposition and molecular beam ***,these complicated preparation processes,as well as their high cost,limit their extensive *** is essential to develop a simple solution process for building ***,we demonstrate an ion exchange strategy for synthesizing an allinorganic superlattice cesium lead bromide/layered double hydroxides(CsPbBr_3/LDH)in *** room temperature,the perovskite ions diffuse into the interlayer of LDH and assemble into layered perovskite with various *** with traditional organic-inorganic hybrid perovskite superlattice,the all-inorganic perovskite superlattice CsPbBr_(3)/LDH has weak quantum confinement,which exhibits narrow emission line-widths of 20 nm,high quantum yields of 55%,and radiative lifetimes of several *** findings offer a new route to synthesize novel perovskite superlattices and enrich the perovskite supercrystal platform for electronics,photonics and optoelectronics devices.

关键词： halide perovskite superlattice layered double hydroxides 2D

FeNi Prussian blue analogues on highly graphitized carbon nanosheets as efficient glucose sensors

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Rare Metals 2024年第6期43卷 2730-2738页

作者： Jin-Hang Xue Qiu-Hong Sun Cheng Han Yuan-Dong Yang Shao-Jie Xu Qi-Peng Li Jin-Jie Qian college of Life and Environmental Science Wenzhou UniversityWenzhou 325000China college of chemistry and Materials engineering Wenzhou UniversityWenzhou 325000China college of chemistry and Chemical engineering Zhaotong UniversityZhaotong 657000China

Meeting the continuous glucose monitoring requirements of individuals necessitates the research and development of sensors with high sensitivity and *** this study,a straightforward strategy was proposed for synthesizing ultra-thin oxygen-rich graphitized carbon nanosheets(denoted as GCS-O).These nanosheets are obtained by calcining a topologically two-dimensional indium-based coordination ***,the growth of FeNi Prussian blue analogue(PBA)on GCS-O effectively introduces active sites and increases the nitrogen content within the carbonaceous *** resulting FeNi-PBA/GCS-O composite exhibits excellent glucose sensing performance with a broad linear range of 1 to 1300μmol·L^(-1).Meanwhile,it also achieves a high sensitivity of 2496μA·mmol^(-1)·L·cm^(-2),a limit of detection of 100nmol·L^(-1)(S/N=3),and commendable long-term *** relatively simple synthesis process,exceptional sensitivity,and satisfactory electrochemical sensing performance of FeNi-PBA/GCS-O open up new directions for biosensor applications.

关键词： Coordination polymer Carbon nanosheet Prussian blue analogue Surface reconstruction Glucose oxidation

Construction of remote cyano-substituted quaternary carbon centers via nickel-catalyzed migratory hydrocyanation of unconjugated dienes

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Science China chemistry 2024年第10期67卷 3397-3405页

作者： Yidan Xing Rongrong Yu Mingdong Jiao Ting Wang Xianjie Fang Shanghai Key Laboratory for molecular engineering of Chiral Drugs School of Chemistry and Chemical EngineeringShanghai Jiao Tong University Key Laboratory of Organosilicon chemistry and Material Technology of Ministry of Education Key Laboratory of Organosilicon Material Technology of Zhejiang ProvinceCollege of MaterialChemistry and Chemical EngineeringHangzhou Normal University

The transition-metal-catalyzed migratory functionalization has emerged as a robust protocol for the building of C–C bonds remote from the “initiation” position. However, a similar strategy for the construction of quaternary carbon centers is still underdeveloped and only a limited number of reports exist. Herein, we report a nickel-catalyzed migratory hydrocyanation of unconjugated dienes to construct remote cyano-substituted quaternary carbon centers. This transformation features exceptional regioselectivity, mild reaction conditions, broad substrate scope and high yields. The synthetic utility of this method has been highlighted by a series of product derivatizations, and the potential of this transformation has been extended to synthesize TRPV1 antagonist and the key intermediate in the total synthesis of quebrachamine. Density functional theory(DFT) studies unveiled that the specific catalytic pocket assumed a significant role in the selective formation of cyano-substituted quaternary carbon centers.

关键词： chain-walking regioselectivity remote cyanation quaternary carbon centers unconjugated dienes