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Key progresses of MOE key laboratory of macromolecular synthesis and functionalization in 2022

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Chinese Chemical Letters 2024年第3期35卷 114-126页

作者： Xumeng Deng Kaihao Chen Kai Pang Xiaoting Liu Minsong Gao Jie Ren Guanwen Yang Guangpeng Wu Chengjian Zhang xufeng ni Peng Zhang Jian Ji Jianzhao Liu Zhengwei Mao Ziliang Wu Zhen Xu Haoke Zhang Hanying Li MOE Key Laboratory of Macromolecular Synthesis and Functionalization International Research Center for X PolymersDepartment of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

In 2022,The MOE Key Laboratory of Macromolecular Synthesis and Functionalization in Zhejiang University had achieved several important ***,a series of well-defined dinuclear organoboron catalysts were developed to precisely control the enchainment of ether and carbonate segments during the copolymerization of CO_(2)and ***,polyester had been synthesized through cationic copolymerization of cyclic ***,ring-opening polymerization of carbon dioxide based valerolactone had been achieved,revealing the prospect of 3-ethylidene-6-vinyltetrahydro-2H-pyran-2-one(EVL)in utilizing CO_(2)and synthesizing functional ***,machine learning methods have been applied to biomaterial research,enabling high-throughput screening of functional biomaterial surfaces for implantable devices,and searching for potent antimicrobial peptides in whole combinatorial peptide ***,methods of characterization of biomacromolecule RNA transcription and manipulation of nucleoside modification were ***,artificial enzymes-armed Bifidobacterium Longum probiotics were established to tune down gut ***,three-dimensional(3D)printing technologies were used to engineer tough supramolecular ***,hydroplastic foaming graphene frameworks for acoustic and conductive polymer composites were provided for ***,aggregate photophysics about the nature of through-space interactions(TSIs)and manipulating their strength in small molecules with non-conjugated structure had been ***,the forming mechanism of a newfound nested texture in poly(L-lactic acid)(PLLA)spherulitic films had been ***,the isotropically dyeing mechanism of KDP single crystals grown from hydrogels have been *** related works are reviewed in this paper.

关键词： Polymer Catalyst Biomaterial research mRNA Hydrogel Graphene Crystal

Room temperature polymerization of alkyl isocyanates catalyzed by rare earth Schiff base complexes

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Science China Chemistry 2009年第11期52卷 1843-1850页

作者： XiongFa Yang xufeng ni ZhiQuan Shen Key Laboratory of Macromolecular Synthesis and Functionalization Ministry of Education Institute of Polymer Science Zhejiang University Hangzhou 310027 China

The polymerization of alkyl isocyanates catalyzed by rare earth chloride salen complexes/triisobutyl aluminum (Ln(H2salen)2Cl3·2C2H7OH/Al(i-Bu)3) at room temperature was investigated. The influences of ligand structure, catalyst composition, polymerization temperature, polymerization time, the concentration of catalyst and monomer, and the polymerization solvent on the polymerization of isocyanates were studied. It was found that under the polymerization conditions, examined La(H2salenA)2Cl3·2C2-H7OH/Al(i-Bu)3 (H2salenA= N,N′-disalicylideneethylene diamine) is a fairly high efficient catalyst for the polymerization of n-hexyl isocyanate (n-HexNCO) to prepare high molecular weight poly(n-hexyl isocyanate) (PHNCO) with narrower molecular weight distribution at room temperature. PHNCO could be prepared with yield of 74.0%, number-average molecular weight (M n) of 40.20×104 and MWD of 1.79 under the following optimum conditions: [Al]/[La] = 30 (molar ratio), [n-HexNCO]/[La] = 100 (molar ratio), [n-HexNCO] = 3.43 mol/L polymerization at 20°C for 12 h in toluene. In the same polymerization conditions, poly (n-octyl isocyanate) (PONCO) with yield of 67.3%, and poly(n-butyl isocyanate) (PBNCO) with yield of 45.5%, could be prepared respectively. The kinetics of the polymerization of n-HexNCO was also investigated and found to be first-order with respect to both monomer and catalyst concentrations.

关键词： rare earth catalyst Schiff base complex polymerization alkyl isocyanate

n-Octyloxyallene homopolymerization and random copolymerization with styrene using catalyst system composed of lanthanide Schiff-base complexes and Al(i-Bu)_3

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Science China Chemistry 2013年第7期56卷 970-976页

作者： JIAO JunQing ZHU WeiWei ni xufeng SHEN ZhiQuan MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University

The catalyst system composed of lanthanide Schiff-base complexes with [3,5-tBu2-2-（O）C6H2CH=NC6Hs]3Ln（THF）（Ln（Salen）3, Ln = Sc, Y, La, Nd, Sm, Gd, Yb） and triisobutyl aluminum shows high activity for n-octyloxyallene （A） homopolymerization with narrow molecular weight distribution （MWD）. The influences of reaction conditions on polymerization behavior are in- vestigated, and poly（n-octyloxyallene） has a weight average molecular weight （Mw） of 20.6 ~ 103 with MWD of 1.39 and 100% yield is obtained under the optimum conditions： [A1]/[Y] = 50 mol/mol, [A]/[Y] = 100 mol/mol, with polymerization at 80 ~C for 16 h in bulk. The kinetic studies of n-octyloxyallene homopolymerization indicate that the polymerization rate is first-order with respect to the monomer concentration and shows some controlled polymerization characteristics. Random co- polymer of n-octyloxyallene with styrene is obtained by using the same binary catalyst system; the reactivity ratios of the comonomer determined by Kelen-Ttld/Ss method are rA = 1.20 and rst = 0.35, respectively, the ratio of each segment and Mw of the resulting copolymer could be controlled by varying the feed ratio of each monomer. Determined by differential scanning calorimetry, the copolymers obtained show only one glass transition temperature, which increases gradually with the increase of styrene content in the copolymer.

关键词： n-octyloxyallene styrene lanthanide Schiff-base coordination polymerization

稀土席夫碱配合物催化己内酯可控开环聚合(英文)

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催化学报 2010年第8期31卷 965-971页

作者：倪旭峰朱伟伟沈之荃浙江大学高分子科学与工程学系教育部高分子合成与功能构造重点实验室浙江杭州310027

通过稀土氯化物与席夫碱钠盐的交换反应制备了一系列以3,5-二叔丁基水杨醛缩苯胺为配体的稀土席夫碱配合物.对其中的钕席夫碱配合物进行了X射线单晶衍射分析,发现其单晶结构为五角双锥构型,所得席夫碱稀土配合物可以单组分催化ε-己内... 详细信息

通过稀土氯化物与席夫碱钠盐的交换反应制备了一系列以3,5-二叔丁基水杨醛缩苯胺为配体的稀土席夫碱配合物.对其中的钕席夫碱配合物进行了X射线单晶衍射分析,发现其单晶结构为五角双锥构型,所得席夫碱稀土配合物可以单组分催化ε-己内酯开环聚合.深入研究了钕席夫碱配合物催化己内酯的开环聚合机理,考察了不同聚合条件对单体转化率、产物分子量及分子量分布的影响.结果表明,该聚合反应速率为一级,聚合反应具有较好的可控性.聚合物端基分析表明,聚合反应以配位-插入机理进行.

关键词：己内酯开环聚合稀土催化剂席夫碱晶体结构

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苯氧基亚胺钛催化降冰片烯与1-辛烯共聚合

高等学校化学学报 2018年第8期39卷 1853-1858页

作者：孟嘉锋倪旭峰郑豪沈之荃高分子合成与功能构造教育部重点实验室浙江大学高分子科学与工程学系杭州310027 浙江大学海洋学院海洋化学与环境研究所舟山316021

以3,5-二叔丁基水杨醛缩苯胺氯化钛(Ti)、三异丁基铝(Al)和四(五氟苯基)硼酸三苯基甲酯(B)组成的三元催化体系实现了降冰片烯(NBE)与1-辛烯(OC)的共聚合,得到NOC无规共聚物.探索了催化剂组成、聚合时间及聚合温度等对共聚合反应的影响.... 详细信息

以3,5-二叔丁基水杨醛缩苯胺氯化钛(Ti)、三异丁基铝(Al)和四(五氟苯基)硼酸三苯基甲酯(B)组成的三元催化体系实现了降冰片烯(NBE)与1-辛烯(OC)的共聚合,得到NOC无规共聚物.探索了催化剂组成、聚合时间及聚合温度等对共聚合反应的影响.结果表明,当n(Al)/n(Ti)=5∶1,n(B)/n(Ti)=1∶1,n(Monomer)/n(Ti)=400∶1,n(NBE)/n(OC)=5∶5时,于40℃在甲苯中聚合6 h,共聚合产率达到43.7%,2种单体的竞聚率分别为rNBE=3.01;rOC=0.08.改变助催化剂三异丁基铝的用量可在一定范围内调节所得NOC无规共聚物的分子量及分子量分布(MWD),得到Mw=3.0×104~6.5×104,MWD=1.91~2.45的NOC共聚物.NOC无规共聚物具有饱和的主链结构且带有较长的侧链,其玻璃化转变温度较高(约87~174℃),并对NOC无规共聚物组成具有很强依赖性.NOC共聚物的热分解温度超过300℃,热稳定性能优异.

关键词：苯氧基亚胺钛降冰片烯 1-辛烯无规共聚物热稳定性

离子液体支载稀土催化剂催化2,2-二甲基-三亚甲基碳酸酯均聚及其与ε-己内酯的共聚

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催化学报 2007年第7期28卷 588-590页

作者：熊玉兵倪旭峰樊玲沈之荃西北师范大学化学化工学院甘肃省高分子材料重点实验室甘肃兰州730070 浙江大学高分子科学与工程系高分子科学研究所教育部大分子合成与功能构造重点实验室浙江杭州310027

首次合成了离子液体支载稀土催化剂,并探讨了其催化2,2-二甲基-三亚甲基碳酸酯(DTC)均聚及其与ε-己内酯(ε-CL)的共聚,结果表明该新型催化剂能有效地催化DTC的均聚及其与ε-CL的共聚.研究了不同稀土以及加料顺序等反应条件对聚合的影响... 详细信息

首次合成了离子液体支载稀土催化剂,并探讨了其催化2,2-二甲基-三亚甲基碳酸酯(DTC)均聚及其与ε-己内酯(ε-CL)的共聚,结果表明该新型催化剂能有效地催化DTC的均聚及其与ε-CL的共聚.研究了不同稀土以及加料顺序等反应条件对聚合的影响,发现轻稀土的催化活性比重稀土高,其中离子液体支载La催化剂的催化活性最高,而通过控制不同的加料顺序可以制备DTC和ε-CL的无规及嵌段共聚物.对共聚物结构进行了表征.

关键词：稀土离子液体 2,2-二甲基-三亚甲基碳酸酯 ε-己内酯共聚

Recent progress in MnBi2nTe3n+1 intrinsic magnetic topological insulators: crystal growth, magnetism and chemical disorder

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National Science Review 2024年第2期11卷 65-80页

作者： Chaowei Hu Tiema Qian ni ni Department of Physics and Astronomy and California Nano Systems Institute University of California-Los Angeles

The search for magnetic topological materials has been at the forefront of condensed matter research for their potential to host exotic states such as axion insulators, magnetic Weyl semimetals, Chern insulators,etc. To date, the MnBi2nTe3n+1family is the only group of materials showcasing van der Waals-layered structures, intrinsic magnetism and non-trivial band topology without trivial bands at the Fermi level. The interplay between magnetism and band topology in this family has led to the proposal of various topological phenomena, including the quantum anomalous Hall effect, quantum spin Hall effect and quantum magnetoelectric effect. Among these, the quantum anomalous Hall effect has been experimentally observed at record-high temperatures, highlighting the unprecedented potential of this family of materials in fundamental science and technological innovation. In this paper, we provide a comprehensive review of the research progress in this intrinsic magnetic topological insulator family, with a focus on single-crystal growth, characterization of chemical disorder, manipulation of magnetism through chemical substitution and external pressure, and important questions that remain to be conclusively answered.

关键词： MnBi2Te4 magnetic topological insulator magnetism tuning antiferromagnetism ferromagnetism pressure chemical doping

Schiff碱镧配合物的合成及其催化烷基异氰酸酯聚合

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高分子学报 2011年第5期21卷 475-480页

作者：焦俊卿杨雄发倪旭峰教育部高分子合成与功能构造重点实验室浙江大学高分子科学研究所杭州310027 杭州师范大学有机硅化学及材料技术教育部重点实验室杭州310012

通过氯化镧与Schiff碱钠盐(NaSalen)的交换反应制备了4种镧的Schiff碱配合物La(HSalen1～4)3,对其中以3,5-二叔丁基水杨醛缩苯胺为配体的配合物La(HSalen2)3进行了X-射线单晶衍射分析,测定其单晶结构为五角双锥构型,七配位的镧金属中心... 详细信息

通过氯化镧与Schiff碱钠盐(NaSalen)的交换反应制备了4种镧的Schiff碱配合物La(HSalen1～4)3,对其中以3,5-二叔丁基水杨醛缩苯胺为配体的配合物La(HSalen2)3进行了X-射线单晶衍射分析,测定其单晶结构为五角双锥构型,七配位的镧金属中心与氮和氧原子相连.将所得的La(HSalen)3配合物作为单组份催化剂用于催化烷基异氰酸酯聚合,发现以水杨醛缩苯胺为配体的配合物La(HSalen1)3的催化活性最高.深入研究了配合物La(HSalen1)3催化的己基异氰酸酯(HIC)的聚合,详细考察了催化剂用量、单体浓度、聚合时间和温度以及聚合溶剂等对单体转化率、产物分子量及分子量分布的影响.研究结果表明,在-40～20℃温度范围内,配合物La(HSalen1)3均可以催化己基异氰酸酯聚合,得到黏均分子量10×104～50×104之间的聚己基异氰酸酯(PHIC),由于存在解聚反应,提高聚合温度和延长聚合反应时间均导致聚合物分子量降低,分布变宽.适宜的聚合条件为:[HIC]=3.43 mol/L,[La]=8.58×10-3 mol/L,-40℃甲苯溶液中聚合12 h,得到的聚合物产率75.5%,Mv=35.4×104,MWD=3.86.

关键词：稀土 Schiff碱配合物异氰酸酯聚合

Regional features of pollen R-values in China

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Science China Earth Sciences 2024年第1期67卷 295-308页

作者： Jie XIA Jian ni College of Life Sciences Zhejiang Normal UniversityJinhua 321004China Jinhua Mountain Observation and Research Station for Subtropical Forest Ecosystems Jinhua 321004China

Establishing a quantitative relationship between modern pollen and vegetation remains a pivotal but intricate pursuit within the field of Quaternary *** R-value,a well-established and traditional metric characterized by its simplicity and direct applicability,serves to calibrate the nonlinear disparities between surface pollen and modern *** study entails the construction of a comprehensive pollen R-value dataset for China derived from R-values published between 1987 and *** dataset,compiled after rigorous screening,calibration,and standardization processes,encompasses 898 modern pollen sampling sites and 2115 pollen R-value data entries,encapsulating 152 pollen taxa spanning 65 families and 113 *** the extracted R-values yielded the following insights:(1)A macrospatial analysis validates previously established knowledge at a site-specific ***,pollen R-value variations across China are statistically *** two-thirds of pollen taxa exhibit underrepresentation(e.g.,Taxodiaceae,Corylus,nitraria,Tamarix,Cyperaceae,Poaceae,and Fabaceae),while the remaining one-third display overrepresentation(e.g.,Pinus,Picea,Betula,Ephedra,Chenopodiaceae,and Artemisia).The degree of underrepresentation surpasses that of overrepresentation,and the representation patterns of Castanea,Quercus,Polygonaceae,and Asteraceae are contingent upon vegetation types.(2)Pollen R-values follow distinct spatial distribution patterns within *** the woody vegetation region of eastern China,R-values progressively decline from north to south,correlating with rising temperatures and ***,in herbaceous vegetation regions of northern and western China,R-values decrease from east to west and from northeast to southwest,corresponding to increased ***,pollen R-values manifest variation contingent on pollen taxa,vegetation types,and climatic regions,even differing for the same taxa across varying

关键词： Pollen R-value Modern pollen-vegetation relationship Regional pattern Variability Paleovegetation reconstruction