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Synthetic rubbers prepared by lanthanide coordination catalysts

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Science China Chemistry 2009年第10期52卷 1520-1543页

作者： WenQi Chen fosong wang Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China

China is rich in rare earth resources. Rare earth elements, also named lanthanides, are number 58 to number 81 elements in the elemental periodic table. They have unique electronic structures and may form various coordination compounds. In the early 1960s, researchers at the Changchun Institute of Applied Chemistry, Chinese Academy of Sciences (CIAC) found the catalytic activities of lanthanide compounds in stereospecific polymerization of conjugated dienes, and published the first paper on this topic in 1964. On the basis of this finding, CIAC launched extensive research activities on lanthanide compounds as diene polymerization catalysts, from a series of fundamental research to the efforts of industrializing the rare earth catalyzed cis-1,4-polybutatine rubber and cis-1,4-polyisoprene rubber. This review aims to summarize the progress in this field in the past half century.

关键词： synthetic rubber polybutadiene polyisoprene rare earth lanthanide coordination catalysts stereospecific polymerization

Temperature-responsive Catalyst for the Coupling Reaction of Carbon Dioxide and Propylene Oxide

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Chinese Journal of Chemistry 2018年第4期36卷 299-305页

作者： ChunweiZhuo Yusheng Qin Xianhong wang fosong wang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 China University of Science and Technology of China Hefei Anhui 230026China

The selective synthesis of polypropylene carbonate （PPC） and cyclic propylene carbonate （CPC） from coupling reaction of CO_2 and propylene oxide （PO） is a long term pursuing target. Here we report that a temperature controllable porphyrin aluminum catalyst using 5,10,15,20-tetra（1,2,3,4,5,6, 7,8-octahydro-1,4：5,8-dimethanoanthracen-g-yl）porphyrin as ligand, once in conjunction with suitable onium salt, achieved single cycloaddition or co- polymerization reaction. Only cydoaddition reaction happened at temperature above 75 ℃ to produce 100% CPC, whereas copolymerization became dominant to afford PPC with selectivity over 99% at 25℃, and the obtained PPC showed over 99% carbonate linkage and 92% head-to-tail structure. Based on systematic analysis of the electronic and steric feature in the porphyrin ligand, it was found that the electronic feature of the substituent in porphyrin ligand was decisive for PPC selectivity, porphyrin ligand bearing strong electron-donating substituents displayed a significantly reduced toler- ance towards increased temperature with respect to PPC formation. Therefore, temperature-responsive catalyst could be designed by suitable modifica- tion in porphyrin ligand, and such accurate synthesis of target product by one catalyst may create a useful and facile platform for selective PPC or CPC production.

关键词： carbon dioxide propylene oxide copolymerization cycloaddition aluminum porphyrin

Controlled synthesis of CO_2-diol from renewable starter by reducing acid value through preactivation approach

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Science China Chemistry 2016年第11期59卷 1369-1375页

作者： Shunjie Liu Yusheng Qin Hongchen Guo Xianhong wang fosong wang University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Synthesis of polyols from carbon dioxide（CO2） is attractive from the viewpoint of sustainable development of polyurethane industry;it is also interesting to adjust the structure of the CO2-polyols for versatile requirement of ***,when renewable malonic acid was used as a starter,the copolymerization reaction of CO2 and propylene oxide（PO） was uncontrollable,since it proceeded slowly（13 h） and produced 40.4 wt%of byproduct propylene carbonate（PC） with a low productivity of 0.34kg/g.A careful analysis disclosed that the acid value of the copolymerization medium was the key factor for controlling the copolymerization ***,a preactivation approach was developed to dramatically reduce the acid value to 0.6mg（KOH）/gby homopolymerization of PO into oligo-ether-diol under the initiation of malonic acid,which ensured the controllable copolymerization,where the copolymerization time could be shortened by 77%from 13 to 3 h,the PC content was reduced by 76%from 40.4 wt%to 9.4 wt%,and the productivity increased by 61%from 0.34 to 0.55 kg/***,by means of preactivation approach,the molecular weight as well as the carbonate unit content in the CO2-diol was also controllable.

关键词： CO_2-polyols renewable starter acid value controllable copolymerization preactivation approach

Chain-transfer-catalyst: strategy for construction of site-specific functional CO_(2)-based polycarbonates

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Science China Chemistry 2022年第1期65卷 162-169页

作者： Enhao wang Shunjie Liu Han Cao Chunwei Zhuo Xianhong wang fosong wang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Science and Technology of China Hefei 230026China

Site-specific functional polymers are generally synthesized from functionalized chain transfer agents(CTA)in the presence of ***,the poor solubility or chemical inertness of CTAs may make polymerizations ***,this issue is addressed by proposing a strategy of designing chain-transfer-catalyst(CTC)that combines catalyst and CTA into *** occurrence of catalytic effect naturally triggers the chain transfer process to give catalyst-labeled polymers with well-defined *** a proof-of-concept,cobalt(III)porphyrin catalysts with one,two and four hydroxyl groups act as efficient CTCs,giving the corresponding site-specific functional poly(propylene carbonate)s(PPC),diversifying the topology of ***,porphyrin-capped PPCs with controllable Mn in the range of 1,000–16,800 g mol^(-1)were obtained by using monofunctional CTC(CTCOH).Moreover,different from traditional“catalyst+CTA”systems,a novel dynamic network transfer mechanism of CTCOH was *** study provides a CTC strategy for the synthesis of site-specific functional polymers.

关键词： chain-transfer-catalyst metalloporphyrin complex immortal polymerization CO_(2)copolymerization

Dithienocarbazole- and benzothiadiazole-based donor-acceptor conjugated polymers for bulk heterojunction polymer solar cells

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Science China Chemistry 2015年第2期58卷 294-300页

作者： Ziqing Rong Yunfeng Deng Zhiyuan Xie Yanhou Geng fosong wang State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences University of Chinese Academy of Sciences

Donor-acceptor （D-A）-conjugated polymers P（BT-C1） and P（BT-C2）, with dithieno[2,3-b;7,6-b]carbazole （C1） or dithi- eno[3,2-b;6,7-b]carbazole （C2） as D-unit and benzothiadiazole （BT） as A-unit, were synthesized. The optical bandgaps of the polymers are similar （1.84 and 1.88 eV, respectively）. The structures of donor units noticeably influence the energy levels and backbone curvature of the polymers. P（BT-C1） shows a large backbone curvature; its highest occupied molecular orbital （HOMO） energy level is -5.18 eV, whereas P（BT-C2） displays a pseudo-straight backbone and has a HOMO energy level of -5.37 eV. The hole mobilities of the polymers without thermal annealing are 1.9×10^-3 and 2.7×10^-3 cm^2 V-1 s^-1 for P（BT-C1） and P（BT-C2）, respectively, as measured by organic thin-film transistors （OTFTs）. Polymer solar cells using P（BT-C1） and P（BT-C2） as the donor and phenyl-Cyl-butyric acid methyl ester （PCyLBM） as the acceptor were fabricated. Power conversion efficiencies （PCEs） of 4.9% and 5.0% were achieved for P（BT-C1） and P（BT-C2）, respectively. The devices based on P（BT-C2） exhibited a higher Voc due to the deeper HOMO level of the polymer, which led to a slightly higher PCE.

关键词： conjugated polymer dithienocarbazole benzothiadiazole polymer solar cells power conversion efficiency

Self-host yellow iridium dendrimers based on carbazole dendrons: synthesis, characterization and application in solution-processed organic light-emitting diodes

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Science China Chemistry 2016年第12期59卷 1593-1599页

作者： Bin wang Shiyang Shao Junqiao Ding Lixiang wang Xiabin Jing fosong wang State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences

On the basis of different generation carbazole dendrons, a series of self-host yellow Ir dendrimers （Y-G0, Y-G1 and-G2） have been successfully synthesized and characterized in detail. It is found that the peripheral dendrons can effectively reduce the intermolecular interactions between emissive Ir cores, as verified by the increased photoluminescence quantum yields and film lifetimes. Among these dendrimers, Y-G2 bearing the second generation dendrons shows the best non-doped device per- formance, revealing a peak luminous efficiency of 20.2 cd/A. The value is nearly twice that of Y-G0 without any dendrons, which could be further improved to 32.1 cd/A by dispersing Y-G2 into a host matrix. We believe that this work will shed light on the development of highly efficient yellow phosphorescent dendrimers with a self-host strategy.

关键词： iridium dendrimers carbazole self-host solution-processed OLEDs

Construction of Self-Reporting Biodegradable CO_(2)-Based Polycarbonates for the Visualization of Thermoresponsive Behavior with Aggregation-Induced Emission Technology

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Chinese Journal of Chemistry 2021年第11期39卷 3037-3043页

作者： Molin wang Enhao wang Han Cao Shunjie Liu Xianhong wang fosong wang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchunJilin130022 China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefeiAnhui230026 China

Thermoresponsive polymers with simultaneous biodegradability and signal“self-reporting”outputs that meet for advanced applications are hard to *** address this issue,we developed fluorescence signal“self-reporting”biodegradable thermoresponsive polycarbonates through the immortal copolymerization of CO_(2)and oligoethylene glycol monomethyl ether-functionalized epoxides in the presence of hydroxyl-modified tetraphenylethylene(TPE-OH).TPE-OH was used as chain transfer agent to afford well-defined polycarbonates with controlled molecular weight(6000—17000 g·mol^(–1))and aggregation-induced emission *** temperature-dependent fluorescence intensity study,low critical solution transition of TPE-labeled polycarbonates were determined and the fine details of thermal-induced phase transition process were *** research indicated that temperature-controlled aggregation and dissociation of TPE moieties are the main reason for fluorescence intensity *** anticipate that this work could offer a method to visualize the thermal transition process of thermoresponsive polycarbonates and broaden their application fields as smart materials.

关键词： Ring-opening polymerization Fluorescence Thermoresponsive polymers Phase transitions Visualization CO_(2)copolymerization

Through-space charge transfer blue polymers containing acridan donor and oxygen-bridged triphenylboron acceptor for highly efficient solution-processed organic light-emitting diodes

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Science China Chemistry 2020年第8期63卷 1112-1120页

作者： Fan Chen Jun Hu Xingdong wang Shiyang Shao Lixiang wang Xiabin Jing fosong wang State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Three kinds of through-space charge transfer(TSCT)blue polymers containing non-conjugated polystyrene backbone together with spatially-separated acridan donor and oxygen-bridged triphenylboron acceptors having different substituents of tert-butyl,hydrogen and fluorine are designed and *** designed TSCT blue polymers possess photoluminescence quantum yields up to 70%in solid-state film,single-triplet energy splitting below 0.1 eV,and typical thermally activated delayed fluorescence(TADF)***,the resulting polymers exhibit aggregation-induced emission(AIE)effect with emission intensity increased by up to^27 folds from solution to aggregation *** changing the substituent of acceptors to tune the charge transfer strength,blue emission with peaks from 444 to 480 nm can be realized for the resulting ***-processed organic light-emitting diodes based on the polymers exhibit excellent device performance with Commission Internationale de L’Eclairage(CIE)coordinates of(0.16,0.27),together with the maximum luminous efficiency of 30.7 cd A-1 and maximum external quantum efficiency of 15.0%,which is the best device efficiency for blue TADF polymers.

关键词： through-space charge transfer thermally activated delayed fluorescence oxygen-bridged triphenylboron electroluminescent polymer organic light-emitting diodes

Effect of polymer chain structure and chain distance on luminescent efficiency

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Chinese Science Bulletin 1998年第12期43卷 1015-1018页

作者： Hong Zhiyong Zhao Xiaojiang Ma Dongge wang Daike Jing Xiabin wang fosong Chinese Acad Sci Changchun Inst Appl Chem Changchun 130022 Peoples R China

Three kinds of PPV-based copolymers were synthesized and characterized. Their luminescent properties were investigated and discussed by PL spectrum, and time-dependence luminescent spectrum in film and solution state. The results show that in the range of our study, the PL intensity and lifetime of luminescent decay increase with the increasing length of flexible segments and the solution diluting, indicating the tendency of the increase of luminescent efficiency.

关键词： polymer luminescent efficiency lifetime of luminescent decay and polymer LEDs.