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Chinese Journal of Chemistry 2024年第6期42卷 652-685页

作者： Tharinee Theerathanagorn Tanika Kessaratikoon Hafeez Ur Rehman Valerio D'Elia Daniel Crespy VISTEC Advanced Laboratory for Environment-Related Inorganic and Organic Syntheses Department of Materials Science and EngineeringVidyasirimedhi Institute of Science and Technology21210Wang ChanRayongThailand Department of Materials Science and Engineering Vidyasirimedhi Institute of Science and Technology21210Wang ChanRayongThailand

Polyhydroxyurethanes(PHUs)have received considerable attention in the last decade as potential alternatives to traditional phosgene-based polyurethanes(PUs).The development of suitable 5CC(five membered-ring cyclic carbonate)precursors bearing multiple carbonate moieties(multi-5CCs)is a key requisite for preparing PHUs by polyaddition reaction with bis-or *** sustainable PHUs from CO_(2)-based five-membered cyclic carbonates(5CCs)obtained from biobased epoxides is a valuable strategy to bridge CO_(2) utilization and the upcycling of renewable *** this context,while many multi-5CC monomers reported in the literature are oil-based,recent efforts have led to the development of a large variety of multifunctional 5CCs that are produced by the combination of CO_(2) and renewable resources such as fatty acids and vegetable oils,lignin,terpenes,and *** this work,recent crucial advances(2019—2023)on PHUs prepared from bis-and multi-5CCs produced from CO_(2) and(partially/potentially)biobased substrates are reviewed with respect to their synthesis,thermal and mechanical properties,and their recent,emerging applications.

关键词： CO_(2) conversion Polyhydroxyurethanes Cyclic carbonates Biobased compounds Fatty acids Functional polymers monomers Renewable resources

Ethylene Polymerization and Copolymerization with Polar monomers by Benzothiophene-bridged BPMO-Pd Catalysts

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Chinese Journal of Polymer Science 2020年第6期38卷 579-586页

作者： Hong-Liang Mu Jun-Hao Ye Guang-Lin Zhou Kang-Kang Li Zhong-Bao Jian State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

A series of new bisphosphine-monoxide(BPMO)ligands based on benzothiophene backbone and the corresponding palladium complexes{k2-P(O)(Ph)2-3-PR1R2-C8H4S}PdMeCl{2a:R1=R2=Ph;2b:R1=R2=2-0Me-Ph;2c:R1=R2=2-CF3-Ph;2d:Rl=Ph,R2=2-(2',6'-(OMe)2C6Hz)-C6H4}were synthesized and fully characterized by1H-,13C-,31P-,and 2D-NMR spectroscopy and single-crystal X-ray *** the presence of Na+B[3,5-(CF3)2C6H3]4(NaBArF),these complexes showed very high activities(up to 2.0 x 10’g-mol-1.h-)for ethylene *** significantly,these catalysts enabled the copolymerization of ethylene with a broad scope of commercially available polar comonomers such as acrylates,acrylic acid,acrylonitrile,vinyltrialkoxysilane,allyl acetate,and long-chain 6-chloro-1-hexene to give functionalized polyethylene with reasonable catalytic activities(up to 105 g-mol-l.h-)and incorporations(up to 5.3 mol96).This contribution suggests that,besides the modulation of conventionally steric and electronic factors,the connectivity(at dfferent linking positions)of BPMO(P,O)donors to the heteroaryl backbone also greatly infuences the catalyst properties in terms of catalytic activity,polymer branching content,comonomer scope,and comonomer incorporation.

关键词： Olefin polymerization Bisphosphine monoxide Plladium Polar monomers Heteroaryl backbone

Influence of the angle between two crown ether moieties on supramolecular copolymerization of bis(crown ether)s and bisparaquat homoditopic monomers

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Science China Chemistry 2010年第5期53卷 1080-1087页

作者： Zhou, QiZhong Jiang, HuaJiang Ding, Liang Wang, Feng Wu, Tao Department of Chemistry Taizhou University Taizhou 317000 China Department of Chemistry Zhejiang University Hangzhou 310027 China

Bis(crown ether) homoditopic monomers containing two bis(p-phenylene)-34-crown-10 moieties with different angles(180° for monomer 3,120°for monomer 4,and 60°for monomer 5) and a complementary bisparaquat homoditopic monomer(7) were designed and *** three bis(crown ether) monomers could organize into linear supramolecular polymers in concentrated solutions in CHCl3/CH3CN with the bisparaquat monomer 7,as demonstrated by 1 H NMR and viscosity studies. The pseudorotaxanes or supramolecular polymers formed from 3+7 and 4+7 had larger values of Ka,p,n,slope 1,and slope 2 than those of 5+*** result was attributed to the greater steric hindrance of compound 5 than that of 3 and 4,which resulted in less effective formation of linear supramolecular polymers from 5 with compound 7 than those from compounds 3 and 4 with compound 7,as also demonstrated by UV-vis method.

关键词： bis(crown ether) bisparaquat homoditopic monomers angle supramolecular copolymerization

New Family of Functionalized monomers Based on Amines: A Novel Synthesis that Exploits the Nucleophilic Substitution Reaction

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Materials Sciences and Applications 2010年第3期1卷 103-108页

作者： Lissette Agüero Luis G. Guerrero-Ramírez Issa Katime 不详

Chemistry modifications are usually performed to introduce specific group that can increase properties and functionality of materials. In this study, we present the synthesis of six new functionalized monomers prepared by nucleophilic substitution reactions. Reaction of aliphatic and aromatic amines with acryloyl chloride at –20ºC, in presence of triethylamine allowed the synthesis of the corresponding amides. Proton nuclear magnetic resonance (1H NMR) spectroscopy, Fourier-transform infrared (FTIR) spectroscopy and ultraviolet- visible (UV-Vis) measurements confirmed the success of the synthesis with a yield over 90%. These compounds emerged as potentially attractive monomers since they can be used to obtain stimuli-sensitive polymeric materials, due to the presence of amide and pyridine groups.

关键词： Functional monomers FTIR NMR Polymer Design UV-Vis

DNA Probe Specifically Binding Protein Heterodimer Rather Than monomers

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Bulletin of the Chinese Academy of Sciences 2019年第2期33卷 115-116页

作者： YAN Fusheng 不详

In a recent effort hunting for cancer biomarkers, researchers from the Institute of Chemistry, Chinese Academy of Science (ICCAS) identified a new DNA aptamer (termed BG2) that only binds to alkaline phosphatase (AP) heterodimer rather than its monomers. This newly-identified DNA aptamer, representing as the first molecular probe reported capable of recognizing a protein dimer, could serve as an important tool to uncover the mystery of this particular protein dimer in a biological context. This study was published in Advanced Science on April 9.

关键词： ICCAS monomers study

Low-Energy Driven Ring-Opening Behavior of Benzocyclobutene Derivatives

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Chinese Journal of Chemistry 2023年第23期41卷 3238-3244页

作者： Ziwei Yuan Quan Sun Jinchong Xiao Pingxia Zhang Konstantin S.Levchenko Dmitry Y.Demin Wenxin Fu Laboratory of Science and Technology on High-Tech Polymer Materials Institute of ChemistryChinese Academy of SciencesBeijing100190 China College of Chemistry and Material Science Hebei UniversityBaodingHebei071002 China University of Chinese Academy of Sciences Beijing100049 China MIREA — Russian Technological University Moscow119454 Russian Federation

It's urgent to develop benzocyclobutene(BCB)-based polymers with low curing temperature for temperature-sensitive applications such as liquid crystal displays(LCDs)and flexible ***,the effect of substituents on the ring-opening behavior of BCB derivatives was *** ring-opening activation energy barriers(ΔGA)of BCB derivatives with one or two substituents on the four-membered alkyl ring were systematically calculated using the B3LYP *** mono-and di-substituted BCBs adopted the conrotatory ring-opening process,obeying the Woodward-Hoffmann's Rules upon *** mono-/di-substituted BCBs exhibited 8.2%—69%lowerΔGA compared with BCB,attributed to the electronic effects of the *** BCBs with both electron-donating and electron-withdrawing groups,e.g.,1-NH_(2)-8-NO_(2)-BCB,demonstrated the lowestΔ*** addition,BCB derivatives with amide/ester/acyloxy group modified on C1 position were synthesized as model molecules,and their ring-opening temperature can be decreased by 20℃ compared to the unsubstituted one,also consistent with our calculation *** work combined theoretical calculation methods with experimental results to provide valuable insights into the design and synthesis of BCB derivatives and next-generation BCB functional packaging materials with low ring-opening temperature.

关键词： Benzocyclobutene Thermosets monomers Low curing temperature Activation energy barrier Electronic effect Captodative effect

Recent Advance in Low-Dielectric-Constant Organosilicon Polymers

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Chinese Journal of Chemistry 2023年第18期41卷 2371-2381页

作者： Jiaren Hou Jing Sun Qiang Fang Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules Shanghai Institute of Organic ChemistryChinese Academy of Sciences345Lingling RoadShanghai 200032China Center for Excellence in Molecular Synthesis Shonghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling RoodShanghai 200032China University of Chinese Academy of Sciences 19 Yuquan RoadShijinshan DistrictBeijing 100049China

Comprehensive Summary,Low dielectric(low-k)organosilicon polymers have received extensive interests from industry and academia due to good electrical insulation,high temperature resistance,flame retardancy and *** attractive properties enable them to be utilized as low-k materials in fabrication of electronic devices in high-frequency communication *** review summarizes recent progress in developing low-k organosilicon polymers,including the synthetic methods and properties of different organosilicon polymers classified according to the chemical *** may provide some inspiration to design new low-k organosilicon polymers for application in the.

关键词： Organosilicon polymers Low dielectric materials Thermosetting resins Functional polymers monomers Resins

Dynamics of Aggregate Growth Through Monomer Birth and Death

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Chinese Physics Letters 2004年第5期21卷 972-975页

作者：柯见洪林振权 SchoolofPhysicsandElectronicInformation WenzhouNormalCollegeWenzhou325027

We investigate the kinetic behaviour of the growth of aggregates through monomer birth and death and propose a simple model with the rate kernels K(k)∝ku and K'(k)∝kv at which the aggregate Ak of size k respectively yields and loses a monomer. For the symmetrical system with K(k) = K'(k), the aggregate size distribution approaches the conventional scaling form in the case of u2 case. Moreover, the typical aggregate size S(t) grows as t1/(2−u) in the u<2 case and increases exponentially with time in the u = 2 case. We also investigate several solvable systems with asymmetrical rate kernels and find that the scaling of the aggregate size distribution may break down in most cases.

关键词： monomers

A Conserved Interaction between SKIP and SMP1/2 Aids in Recruiting the Second-Step Splicing Factors to the Spliceosome inArabidopsis

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Molecular Plant 2016年第12期9卷 1660-1663页

作者： Liu, Lei Wu, Fangming Zhang, Wei Chinese Acad Sci State Key Lab Plant Cell & Chromosome Engn Ctr Agr Res Resources Inst Genet & Dev Biol 286 Huaizhong Rd Shijiazhuang 050021 Hebei Peoples R China Capital Normal Univ Coll Life Sci Beijing 100048 Peoples R China Chinese Acad Sci State Key Lab Plant Genom Natl Ctr Plant Gene Res Beijing Inst Genet & Dev Biol Beijing 100101 Peoples R China

Dear Editor,In eukaryotes, pre-mRNA splicing, a vital gene expression regulation process at the post-transcriptional level, is catalyzed by the spliceosome via two successive transesterifications （Wahl et al., 2009）. The spliceosome is composed of five small nuclear ribonucleoproteins （U1, U2, U4/U6, and U5 small nuclear RNAs and their specific associated proteins） and numerous splicing factors. During splicing, the spliceosome undergoes a set of subcomplexes, E, A, B, aact, B＊,

关键词： Nuclear monomers Photomorphogenesis

A Review of Metallic Fractal Aggregates

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Open Journal of Metal 2011年第2期1卷 17-24页

作者： Rodolfo J. Slobodrian Claude Rioux Michel Piché 不详

Metals are the main components of the Earth’s mass and are characterized by high thermal and electrical conductivity as well as high reflectivity of electromagnetic fields. Finely divided metals are efficient catalysers and this indicates the relevance of surfaces when their ratio to volume becomes large. This is a characteristic of fractal aggregates and their constituent monomers (spheroidal or other) in the micrometer to nanometer scales. Exotic fern shaped aggregates are also produced. All aggregates exhibit large ratios of surface to volume. Condensation of metallic vapours allows to obtain particle sizes much smaller than those obtained via grinding techniques and far superior in purity. Exotic alloys of non miscible metals have been obtained at the micrometer scale. Thermal and laser evaporation methods of metals followed by condensation are described. Low gravity aggregation experiments were also carried out on aircraft in parabolic flight.

关键词： Fractals monomers Aggregates Metals Alloys