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Chinese Journal of Polymer Science 2013年第4期31卷 550-562页

作者： Hua-hua Huang Chuan-hui Zhang Ya-wei Qin Hui Niu 董金勇 CAS Key Laboratory of Engineering Plastics Institute of ChemistryChinese Academy of Sciences University of Chinese Academy of Sciences

In this paper, we review our recent progress in the synthesis and application of styryl-capped polypropylene （PP-t- St）, an excellent reactive polyolefin that is both convenient and efficient in synthesis and facile and versatile in application for preparing advanced polypropylene materials via macromolecular engineering. The synthesis of PP-t-St is made possible by a unique chain transfer reaction coordinated by a bis-styrenic molecule, such as 1,4-divinylbenzene （DVB） and 1,2-bis（4- vinylphenyl）ethane （BVPE）, and hydrogen in typical C2-symmetric metallocene （e.g. rac-Me2Si（2-Me-4-Ph-Ind）2ZrC12, in association with methylaluminocene, MAO） catalyzed propylene polymerization. The regio-selective 2,1- insertion of the styrenic double bond in DVB or BVPE into the overwhelmingly 1,2-fashioned Zr-PP propagating chain enables substantial dormancy of the catalyst active site, which triggers selective hydrogen chain transfer that, with the formed Zr-H species ultimately saturated by the insertion of propylene monomer, results in an exclusive capping of the afforded PP chains by styryl group at the termination end. With a highly reactive styryl group at chain end, PP-t-St has been used as a facile building block in PP macromolecular engineering together with the employment of state-of-the-art synthetic polymer chemistry to fabricate broad types of new polypropylene architectures.

关键词： Polypropylene coordination polymerization Styryl terminal group Macromolecular engineering.

Highly Cis-1,4 Selective polymerization of Conjugated Dienes Catalyzed by ^-heterocyclic Carbene-ligated Neodymium Complexes

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Chinese Journal of Polymer Science 2020年第12期38卷 1305-1312页

作者： Shu Zhang Na Wu Yi-Xian Wu State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Neodymium complexes containing N heterocyclic carbene(NHC)ligands,NdCl5[1,3,R(NCH=)2C]-THF,(Nd1:R=2,6-Pr2C6H3,x=0;Nd2:R=2,6-Et2C6H3,x=1;Nd3:R=2.4,6-Me3C6H2,x=1)were synthesized and employed as precatalysts for the coordination polymerization of conjugated dienes(butadiene and isoprene).In combination with trisobutylaluminium(TIBA),Nd1 promoted butadiene polymerization to produce extremely high cis-1,4(up to 99.0%)polybutadienes with high molecular weight(Mw=250-780 kg·mol 1).The Nd1/TIBA catalytic system also exhibited both high catalytic activity and cis-1,4 selectivity(up to 97.8%)for isoprene *** catalytic activity,molecular weight and molecular weight distribution of resulting polydienes were directly influenced by Al/Nd molar ratio,aging method,and polymerization *** interestingly,the high cis-1,4 selectivity of the catalyst towards butadiene and isoprene kept almost unchanged under different reaction *** cis-1,4 polyisoprenes with high molecular weight(Mw=210-530 kg·mol 1)and narrow molecular weight distribution (Mw/Mn=1.9-2.7)as well as high cis-1.4 selectivity(-~97%)could be synthesized by using the aged Nd1/TIBA catalytic system in the presence of isoprene(100 equivalent to Nd)at low AlNd molar ratios of *** with low molecular weights(Mw=12-76 kg·mol-7)and narrow molecular weight distributions (Mw/Mn=1.7-2.6)were obtained by using Nd2 and Nd3 as precatalysts,indicating that the molecular weight of resulting polyisoprenes can be adjusted by changing the substitutes of ligand in Nd complex.

关键词： Neodymium complex N heterocydic carbene igand coordination polymerization Cis-14 sletivity Aging method

Mono- and Binuclear Cobalt(Ⅱ) Complexes Supported by Quinoline-2- imidate Ligands： Synthesis, Characterization, and 1,3-Butadiene polymerization

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Chinese Journal of Polymer Science 2018年第8期36卷 943-952页

作者： Heng Liu Rui Zhuang Bo Dong FengWang Yan-Ming Hu Xue-Quan Zhang CAS Key Laboratory of Synthetic Rubber Changchun lnstitute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China University of Chinese Academy of Sciences Beijing 100049 China College of Materials Science and Engineering Jilin University Changchun 130022 China

A series of mono-and binuclear Co（Ⅱ） complexes （Col-Co7） supported by quinoline-2-imidate ligands were synthesized and thoroughly characterized. Measured by single crystal X-ray crystallography, complexes Col and Co3 adopted distorted tetrahedral structures around the cobalt center. Upon activation by ethylaluminium sesquichloride （EASC）, these cobalt complexes exhibited high catalytic activity and cis-l,4-selectivity towards 1,3-butadiene polymerization. The effects of ligand environment, polymerization temperature, and cocatalyst types on the polymerization were investigated in detail. Interestingly, the binuclear Co（Ⅱ） complexes exhibited high thermal stability, and the polymer yields were up to 97.2% even at a high temperature of 70 ℃.

关键词： Late transition metal Cobalt(Ⅱ) complexes coordination polymerization Polybutadiene

Optically Active Helical Polyisocyanides Bearing Chiral Phosphine Pendants: Facile Synthesis and Application in Enantioselective Rauhut-Currier Reaction

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Chinese Journal of Polymer Science 2018年第2期36卷 163-170页

作者： Li Zhou Ling Shen Jian Huang Na Liu Yuan-Yuan Zhu Zong-Quan Wu Department of Polymer Science and Engineering School of Chemistry and Chemical Engineering and Anhui Key Laboratory of Advanced Catalytic Materials and Reaction Engineering Hefei University of Technology School of Material and Chemical Engineering Bengbu University

Three novel enantiopure phenyl isocyanide monomers with BH3-protected phosphine functional group were designed and synthesized. polymerization of these monomers using a alkyne-Pd（II） complex as a catalyst led to the formation of respective helical polyisocyanides in high yields with controlled molecular weights（Mns） and narrow molecular weight distributions（Mw/Mns）. Removing the protecting BH3 groups afforded helical poly（phenyl isocyanide）s bearing phosphine pendants. Thanks to the chiral induction of monomer, the isolated helical polyisocyanides showed high optical activity, as revealed by circular dichroism（CD） and absorption spectroscopies and polarimetry. The helical structures of these polymers were quite stable in various organic solvents with different polarities and in a wide temperature range. Moreover, these helical polymers could be used as organocatalysts and showed good performance in enantioselective cross Rauhut-Currier reaction. The enantiomeric excess（ee） values of the isolated products of cross Rauhut-Currier reaction could be up to 90%. The polymer organocatalysts could be easily recovered from the reaction mixtures and reused at least five times in the reaction without significant loss of their enantioselectivities and catalytic activities.

关键词： Helical polymer Polyisocyanide coordination polymerization Polymer catalyst

Synthesis of Polynorbornene-Poly(ethylene-co-propylene)Diblock Copolymer

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Chinese Chemical Letters 1998年第5期9卷 447-450页

作者： Wu, Q Wen, Q Lu, ZJ Zhongshan Univ Inst Polymer Sci Canton 510275 Peoples R China

Transformation of living ring-opening metathesis polymerization into coordination polymerization by converting the titanacyclobutane group attached to a polynorbornene chain into titanocene alkoxide has been used for the synthesis of polynorbornene-poly(ethylene-co-propylene) block copolymer. Preliminary characterizations of the copolymerization products by solvent extraction and C-13 NMR spectrum are reported.

关键词： ring-opening metathesis polymerization coordination polymerization diblock copolymer norbornene ethylene propylene

polymerization of isoprene catalyzed by neodymium heterocyclic Schiff base complex

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Chinese Chemical Letters 2008年第6期19卷 734-738页

作者： Lei Zhang Xu Feng Ni Wei Lin Sun Zhi Quan Shen Institute of Polymer Science Key Laboratory of Macromolecule Synthesis and Functionalization Ministry of Education Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China

Neodymium-based heterocyclic Schiff base complex was prepared and applied for the coordination polymerization of isoprene. This complex polymerized isoprene to afford products featuring high cis-1,4 stereospecificity （ca. 95%） and high molecular weight （ca, 10^5） in the presence of the triisobutyl aluminium （AliBu3） as cocatalyst, The microstructure of obtained polyisoprene was investigated by FTIR, 1^H NMR. Two different kinds of active centers in the catalyst system were examined by GPC method.

关键词： Heterocyclic Schiff base Neodymium complex Isoprene coordination polymerization

Synthesis of Polyethylenes with In-Chain Isolated Carbonyls from CO_(2)and Ethylene via a Tandem Photoreduction/polymerization Protocol

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CCS Chemistry 2024年第6期6卷 1591-1599页

作者： Fulin Zhou Haojie Dai Shan Tang Yongfeng Zhou Frontiers Science Center for Transformative Molecules Shanghai Key Laboratory for Molecular Engineering of Chiral DrugsSchool of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240

Aiming at accessing polyethylene-bearing in-chain degradable functionality,copolymerization of carbon dioxide(CO_(2))with ethylene has long been recognized as a significant but highly challenging ***,most trials have resulted in ethylene homopolymerization because of the endothermic property and high energy barriers of CO_(2)insertion during polymer chain *** we report an unprecedented tandem reaction protocol for the synthesis of polyethylenes with in-chain carbonyls from CO_(2)and ethylene by the combination of photocatalytic CO_(2)reduction and palladium-catalyzed coordination/insertion *** protocol provides an easy way to adjust the carbonyl content(from 0.13 to 12 mol%)and insertion selectivity(up to 99%isolated carbonyls)of the polyethylene copolymers,which enables the polymers tomaintain the main properties of highdensity polyethylene and simultaneously endows them with good *** addition,besides apolar polyethylene copolymers,polar-functionalized polyethylenes with in-chain isolated carbonyls can also be synthesized from CO_(2),ethylene and a polar monomer using the same *** believe our present work sheds new light on the synthesis of degradable polyethylenes by employing CO_(2)as a green carbonyl source.

关键词： carbon dioxide coordination polymerization polyethylene photoreduction photodegradation

Polymer synthesis by rare earth coordination catalysts

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Progress in Natural Science:Materials International 1995年第6期 3-9页

作者：沈之荃张一烽 China Department of Polymer Science and Engineering Hangzhou 310027 Zhejiang University

The discovery and development of Ziegler-Natta catalyst has opened a new era of polymer science and industry. The Changchun Institute of Applied Chemistry of the Chinese Academy of Sciences has been engaged in developing a new family of Ziegler-Natta type catalysts, which is composed of rare earth compound and aluminum alkyl-rare earth coordination catalyst for diene polymerization since 1960. In 1981, financially

关键词： rare earth catalyst coordination polymerization ring opening polymerization polyalkynes copoly-merization of carbon dioxide polymeric electric conductor.

Facile Access to Polar-Functionalized Ultrahigh Molecular Weight Polyethylene at Ambient Conditions

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CCS Chemistry 2022年第5期4卷 1680-1694页

作者： Xiaoqiang Hu Xiaohui Kang Yixin Zhang Zhongbao Jian State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022 University of Science and Technology of China Hefei 230026 College of Pharmacy Dalian Medical UniversityDalian 116044

The most straightforward and potentially ideal route to produce polar-functionalized polyethylene is direct copolymerization of ethylene with polar ***,access to high-molecular-weight polar copolymers represents one of the biggest challenges in the field of olefin *** this contribution,we report a family of well-designed nickel catalysts that readily address this issue under convenient and highly desired ambient *** 1 bar at 30℃,polar-functionalized ultrahigh number-average molecular weight polyethylenes(UHMWPEs,Mn=0.83-1.10×10^(6) g mol^(−1))are directly *** highest average number of incorporated polar units per polymer chain is *** enhances copolymer molecular weights by two orders of magnitude relative to previous ***,this nickel catalyst family also exceptionally produces the highest number-average molecular weight polyethylenes(Mn=6.04×10^(6) g mol^(−1))at 1 *** Sterimol B1 steric parameter of nickel catalyst quantitatively correlates to polymer molecular *** insights from density functional theory(DFT)calculation reveal that the low barrier(10.4 kcal mol^(−1))of ethylene insertion as the rate-limiting step should be responsible for high activity and the formation of *** coordination-insertion approach is a striking contrast to the high energy free-radical approach.

关键词： coordination polymerization functionalized UHMWPE homogeneous catalysis nickel catalyst polyolefin

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