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Dual roles of trifluoroborate in nickel-catalyzed ethylene polymerization:Electronic perturbation and anchoring for heterogenization

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Chinese Chemical Letters 2023年第8期34卷 352-355页

作者： Changwen Hong Zihao Wang Hui Jiang Guifu Si Maoping Song Changle Chen CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China College of Chemistry Zhengzhou UniversityZhengzhou 450001China

Brookhart-typeα-diimine nickel and palladium catalysts have been extensively studied over the past several decades;however,the heterogenization of these metal complexes has received much less *** this contribution,we installed a trifluoroborate potassium substituent on anα-diimine *** ionic nature of trifluoroborate potassium endowed theα-diimine nickel complex with a strong affinity for the SiO_(2)support,while its electron-donating nature enhanced the catalyst stability and polyethylene molecular *** the presence of only 100 *** Et2AlCl cocatalyst,the SiO_(2)-supported catalyst demonstrated significantly better performance than its homogeneous analog during ethylene polymerization,with extremely high activity(1.42–6.53×10^(7)g mol^(−1)h^(−1))and high thermal *** heterogeneous system led to the formation of high-molecular-weight polyethylenes(Mn 142,500–732,800 g/mol),narrow polydispersities(2.18–3.00),tunable branching densities(21–64 per 1000 carbon atoms),and great mechanical ***,the efficient copolymerization of ethylene with comonomers such as methyl 10-undecenoate,6-chloro-1-hexene or 5-hexenylacetate was *** superior properties enabled by the trifluoroborate potassium moiety may inspire its applications in other polymerization catalyst systems.

关键词： Nickel catalysts Heterogeneous catalysts Olefin polymerization Polar monomer Copolymerization

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Controlled Fabrication of Uniform Digital Nanorods from Precise Sequence-Defined Amphiphilic polymers in Aqueous Media

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Chinese Journal of polymer science 2023年第5期41卷 768-777,I0010页

作者： Qiang-Qiang Shi Xin Zhou Jie Xu Ning Wang Jia-Lin Zhang Xiang-Long Hu Shi-Yong Liu CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China School of Biomedical Engineering and Suzhou Institute for Advanced Research University of Science and Technology of ChinaSuzhou 215123China

Compared with spherical micelles,rod/worm-like micelles not only have extended blood circulation duration,but also exhibit favorable cellular uptake behavior,which is promising for next-generation nanomedicine and ***,the controllable fabrication of narrowly dispersed nanorods in aqueous media is still ***,the methodology of thermal annealing was developed for the fabrication of helical nanorods as well as a series of nanorods with different *** thermal annealing process generally consisted of adding a percentage of organic solvent(10%(V/V)or 20%(V/V))to the digital micellar aqueous dispersion,followed by heating at 90℃for 1 h,then cooling naturally to room temperature,and dialyzing against water to remove the organic ***-handed helical nanorods were afforded by the treatment of 45 nm digital micelles in the presence of 10%(V/V)dioxane,while left-handed helical nanorods were obtained in the presence of 20%(V/V)***,the controlled growth of rod-like digital micelles was achieved after thermal annealing in the presence of different types of organic solvents,and the length of the annealed nanorods was correlated with the types of organic ***,no matter the size of initial digital micelles,they all exhibited similar trend of rod growth in the presence of a certain amount of organic solvent,allowing for controllable formulation of narrowly dispersed *** addition,supramolecular self-assembly by amphiphilic dendritic oligourethane readily fabricated diverse uniform nanorods in aqueous ***,this work provided an attractive methodology to fabricate uniform digital nanorods.

关键词： Sequence-defined amphiphilic polymers Digital nanorods Thermal annealing Dendritic oligourethane Self-assembly

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Scalable preparation and direct visualization of cyclic polymers via self-folding cyclization technique

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science China chemistry 2022年第12期65卷 2558-2566页

作者： Hualong Zhang Hao Zha Chao Liu Chunyan Hong CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei230026China

Cyclic polymers exhibit distinct properties compared with their linear counterparts due to the lack of chain ***,the scalable synthesis of cyclic polymers remains a major challenge,especially for ring-closure ***,we report a novel strategy for large-scale preparation of cyclic polymers,which relies on the prior self-folding of anthracene-telechelic amphiphilic random copolymers(poly((oligo(ethylene glycol)acrylate)-co-(dodecyl acrylate)),P(OEGA-co-DDA))into single-chain polymeric nanoparticles(SCPNs)in *** ultraviolet(UV)-induced cyclization occurs in the hydrophobic *** formation of SCPNs leads to a shortened distance between the end groups of the linear precursors and spatially separated cyclization loci,and significantly enhances the efficiency of UV-induced *** self-folding technique permits access to the synthesis of cyclic polymers not only with high molecular weights(M_(n)>10^(5) g/mol),but also in a decent scale(40 g/L),breaking through the limitations of ring-closure ***,the dense pendants of the copolymers can magnify the macromolecules by increasing the mass density along the backbones,thus making the polymers more readily detectable by the *** transmission electron microscopy(TEM)and atomic force microscopy(AFM)images allow us to observe the topological structures directly and provide crucial evidence to confirm the cyclization.

关键词： cyclic polymer scalable preparation direct visualization self-folding cyclization technique

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Tunable Phase Structure of Side-chain Liquid Crystalline polymers Enabled by Molecular engineering of Dual Mesogenic Cores

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Chinese Journal of polymer science 2024年第10期42卷 1459-1469,I0009页

作者： Wen-Huan Yao Lan-Sheng Liu Jie Zhao Yan-Xia Wang An-Zhi Ma Zheng-Rui Ma Lan-Ying Zhang Ruo-Chen Lan College of Chemistry and Chemical Engineering Hunan UniversityChangsha410082China Key Laboratory of Eco-Functional Polymer Materials of the Ministry of Education Key Laboratory of Eco-Environmental Polymer Materials of Gansu ProvinceCollege of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou730070China Department of Materials Science and Engineering College of EngineeringPeking UniversityBeijing100871China Institute of Advanced Materials&Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education College of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang330022China

A series of novel side-chain liquid crystalline(SCLC)copolymers were synthesized by attaching two distinct mesogenic units,namely a chiral cholesteryl-based monomer(M1)and an achiral biphenyl-based monomer(M2),to a poly(3-mercaptopropylmethylsiloxane)(PMMS)backbone via thiol-ene click *** influence of side chain composition on the self-assembly behavior and phase structures of these SCLC copolymers was systematically investigated using different *** indicate that three distinct liquid crystalline phases and four unique molecular configurations were identified within the polymer series,with the emergence of the liquid crystalline phase being a synergistic outcome of the two distinct side *** study underscores the critical influence of side chain dimensions,rigidity,and spatial volume on the self-assembly structures and phase characteristics of liquid crystalline polymers,providing valuable insights for the rational design and development of advanced functional materials with tailored properties.

关键词： Liquid crystalline copolymers Self-assembly Phase structure Chiral molar ratio

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Transpiration-prompted Photocatalytic Degradation of Dye Pollutant with AuNPs/PANI Based Cryogels

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Chinese Journal of polymer science 2022年第10期40卷 1141-1153,I0006,I0005页

作者： Xiao-Xiao Guo Shi-Chang Hou Jun Chen Cong Liao Wei-Dong He CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China

Incautious discharge of organic dyes such as methyl orange(MO)has produced serious pollution to the environment,calling for the efficient techniques to remove them with retaining the green *** photo-catalytic degradation of organic dyes is promising among the developed ***,a strategy based on transpiration-prompted photocatalytic degradation of dye pollutant under sunlight is put ***(ANI)is graft-polymerized onto poly(acrylamide-co-N-4-aminophenylacrylamide)(PAAm)cryogel embedded with gold nanoparticles(AuNPs,diameter:4-10 nm).The obtained cryogels integrated with AuNPs and PANI inside PAAm matrix(AuNP@PAAm-g-PANI)have been structurally explored based on the chemical composition and the phase/porous *** and TEM observation shows that PANI and AuNPs are uniformly distributed in PAAm *** the macro-porosity of cryogel,hydrophilicity of PAAm and photo-thermal activity of PANI,PAAm-g-PANI cryogels without AuNPs can have a photo-thermal evaporation rate of water at 1.63 kg·m^(-2)·h^(-1).As a comparison,Au NP@PAAm-g-PANI cryogels with AuNPs exhibit higher one at 2.20 kg·m^(-2)·h^(-1),suggesting the promotion of AuNPs to photo-thermal ***,PANI appreciatively assists AuNPs to display higher catalytic ability for the oxidative degradation of ***,the removal of MO from water is obviously prompted by the water transpiration under sunlight with AuNP@PAAm-g-PANI cryogels,whose rate constant can reach to 0.320 h^(-1),being three folds of that for the sole absorption of *** transpiration-prompted photocatalytic degradation provides a fascinating route to eliminate organic pollutants and obtain pure water from wastewater simultaneously with sustainable sunlight energy.

关键词： Photothermal evaporation Photocatalytic degradation Sunlight Organic dye Composite cryogel

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Study on the morphological regulation mechanism of hollow silica microsphere prepared via emulsion droplet template

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Chinese Chemical Letters 2023年第4期34卷 575-579页

作者： Chu Zhao Zhiqing Ge Zhuoni Jiang Shuo Yan Jingjing Shu Mozhen Wang Xuewu Ge CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China School of Materials Science and Engineering Southwest University of Science and TechnologyMianyang 621010China

The morphology regulation of hollow silica microspheres is significant for their properties and applications. In this paper, hollow silica microspheres were formed through the hydrolysis and condensation reaction of tetraethyl orthosilicate(TEOS) at the interface of the emulsion droplet templates composed of liquid paraffin and TEOS, followed by dissolving paraffin with ethanol. The effects of various factors including the emulsifier structure and content, TEOS content, catalyst type, and the ethanol content in the continuous water phase on the particle size, shell thickness and morphology of the prepared hollow silica microspheres were studied in detail. The results show that the diffusion and contact of TEOS and water molecules as well as the hydrolysis condensation reaction of TEOS at the oil-water interface are two critical processes for the synthesis and morphological regulation of hollow silica microspheres. Cationic emulsifier with a hydrophobic chain of appropriate length is the prerequisite for the successful synthesis of hollow silica microspheres. The ethanol content in water phase is the dominant factor to determine the average diameter of hollow microspheres, which can vary from 96 nm to 660 nm with the increase of the volume ratio of alcohol-water from 0 to 0.7. The silica wall thickness varies with the content and the hydrophobic chain length of the emulsifier, TEOS content, and the activity of the catalyst. The component of the soft template will affect the morphology of the silica wall. When the liquid paraffin is replaced by cyclohexane, hollow microspheres with fibrous mesoporous silica wall are fabricated. This work not only enriches the basic theory of interfacial polymerization in the emulsion system, but also provides ideas and methods for expanding the morphology and application of hollow silica microspheres.

关键词： Hollow silica microspheres Emulsion template Morphology regulation mechanism Interfacial polymerization

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New sustainable polymers with on-demand depolymerization property

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science China chemistry 2024年第9期67卷 2803-2841页

作者： Yangyang Sun Zesheng An Yanshan Gao Rongrong Hu Ye Liu Hua Lu Xiao-Bing Lu Xuan Pang Anjun Qin Yong Shen Youhua Tao Yu-Zhong Wang Junpeng Wang Gang Wu Guang-Peng Wu Tie-Qi Xu Xing-Hong Zhang Yuetao Zhang Zhenbiao Zhang Jian-Bo Zhu Miao Hong Zhibo Li State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China State Key Laboratory Base of Eco-Chemical Engineering College of Chemical EngineeringQingdao University of Science and TechnologyQingdao266042China State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular AggregatesSouth China University of TechnologyGuangzhou 510640China State Key Laboratory of Fine Chemicals Frontiers Science Center for Smart MaterialsDalian University of TechnologyDalian 116024China Beijing National Laboratory for Molecular Sciences Center for Soft Matter Science and EngineeringKey Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials(MoE) National Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan)College of ChemistryState Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610064China School of Polymer Science and Polymer Engineering the University of AkronAkronOH 44325USA MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials Jiangsu Key Laboratory of Advanced Functional Polymer Design and ApplicationSuzhou Key Laboratory of Macromolecular Design and Precision SynthesisCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

To combat the crisis of today's synthetic polymers arising from unsustainable production and disposal,it is essential for the synthetic polymer community to reshape the current polymer industry with sustainable *** an emerging class of sustainable polymers,the development of chemically depolymerizable polymers(CDPs),which can undergo closed-loop depolymerization/repolymerization cycles to reproduce virgin polymers without the loss of properties from recovered monomers,offers an ideal solution to preserve finite natural resources,provides a feasible solution to the end-of-life issue of polymer waste,and thereby establishes a circular materials ***,two grand key challenges have been encountered in the establishment of practically useful CDPs:how to balance polymerization and depolymerization ability and how to unify conflicted depolymerizability and physical ***,this critical review article presents our vision for summarizing feasible strategies to overcome the above two significant challenges and the design principles for constructing an ideal CDP by highlighting selected major progress made in this rapidly expanding field.

关键词： chemically depolymerizable polymers sustainable polymers depolymerization monomer recovery degradation plastics

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Translocation of ssDNA through Charged Graphene Nanopores:Effect of the Charge Density

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Chinese Journal of polymer science 2024年第12期42卷 2048-2058,I0013页

作者： Yuan-Shuo Zhang Zhi-Ya Qi Ming-Ming Ding Ming-Lun Li Tong-Fei Shi School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou510006China Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory Jieyang515200China Department of Polymer Science and Engineering University of Massachusetts Amherst120 Governors DriveAmherstMassachusetts01003USA

Nanopore sequencing harnesses changes in ionic current as nucleotides traverse a nanopore,enabling real-time decoding of DNA/RNA *** instruments for the dynamic behavior of substances in the nanopore on the molecular scale are still very limited *** study employs all-atom molecular dynamics(MD)simulations to explore the impact of charge densities on graphene nanopore in the translocation of single-stranded DNA(ssDNA).We find that the magnitude of graphene’s charge,rather than the charge disparity between ssDNA and graphene,significantly influences ssDNA adsorption and translocation ***,high negative charge densities on graphene nanopores are shown to substantially slow down ssDNA translocation,highlighting the importance of hydrodynamic effects and electrostatic *** indicates translocation is crucial for achieving distinct ionic current blockades,which plays a central role for DNA sequencing *** findings suggest that negatively charged graphene nanopores hold considerable potential for optimizing DNA sequencing,marking a critical advancement in this field.

关键词： Nanopore sequencing Graphene nanoslit DNA translocation Electroosmotic flow

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Enhancing the Circularly Polarized Luminescence of Self-assembled Cyanostilbenes through Extended π-Conjugation

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Chinese Journal of chemistry 2024年第2期42卷 135-141页

作者： Tongjin Lv Song Wu Yu Jin Jianfei Ma Sixun Jiang Yuncong Xue Feng Wang Key Laboratory of Precision and Intelligent Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefeiAnhui 230026China Department of Thoracic Surgery Shanghai Jiao Tong University Affiliated Sixth People's HospitalShanghai 200233China

Chiral supramolecular assembly of π-conjugated luminophores provides a promising avenue for enhancing circularly polarized *** this study,we shed light on the impact of π-conjugation length on circularly polarized luminescent performance of the resulting supramolecular assemblies,by designing a tetra-cyanostilbene monomeric compound alongside two dicyanostilbene control *** cyanostilbene-based compounds possess the ability to form chiral supramolecular polymers in toluene,driven by a synergistic combination of intermolecular hydrogen bonding and π-stacking *** extended π π-aromatic skeleton brings bathochromic-shifted fluorescence and enhanced intermolecular stacking capability for the tetra-cyanostilbene ***,chiral supramolecular assemblies formed by the tetra-cyanostilbene compound demonstrate a remarkable two-fold increase in g_(lum) values relative to the assemblies formed by the dicyanostilbene ***,this study provides valuable insights into the relationship between-conjugation length and the circularly polarized luminescent performance of π-conjugatedsupramolecularassemblies.

关键词： Self-assembly Supramolecular polymer Supramolecular chirality Circularly polarized luminescence Cyanostilbene πInteractions Aggregation Nanostructures

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Merging non-covalent and covalent crosslinking:En route to single chain nanoparticles

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Chinese Chemical Letters 2024年第6期35卷 307-311页

作者： Yifei Zhang Yuncong Xue Laiwei Gao Rui Liao Feng Wang Fei Wang CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China Department of Neurosurgical The First Affiliated Hospital of University of Science and Technology of ChinaDivision of Life Sciences and MedicineHefei 230026China

Single-chain nanoparticles represent an emerging class of nanomaterials designed to mimic protein's folding *** covalent crosslinking toward the formation of single-chain nanoparticles encounters complex energy landscapes,leading to the potential occurrence of misfolding *** noncovalent crosslinking can circumvent this issue,the resulting single-chain nanoparticles exhibit lower structural stability compared to their covalently crosslinked *** this study,we present a novel approach for the synthesis of single-chain nanoparticles,achieved through the combination of non-covalent and covalent intramolecular *** grafted onto the linear polymer form intrachain non-covalent stacks aided by hydrogen bonds,leading to the formation of non-covalently crosslinked single-chain *** nanoparticles undergo conversion to covalently crosslinked nanostructures through subsequent photo-irradiation using[2+2]photocycloaddition,a process facilitated by the supramolecular confinement ***,the resulting single-chain nanoparticles demonstrate both intrachain folding efficiency and substantial stability,offering significant potential for advancing applications across diverse fields.

关键词： Single chain nanoparticles Intrachain folding Supramolecular confinement Cyanostilbenes [2+2]photocycloaddition

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