Article
Chemistry, Physical
Shuoyan Xiong, Priyabrata Ghana, Brad C. Bailey, Heather A. Spinney, Briana S. Henderson, Matthew R. Espinosa, Theodor Agapie
Summary: This study demonstrates that the performance of neutral nickel catalysts in ethylene/acrylate copolymerization can be improved by tuning the nature of the labile ligand, L. In situ studies show that a weaker L leads to faster chain propagation and more efficient catalyst initiation.
Article
Polymer Science
Rajkumar S. Birajdar, Samir H. Chikkali
Summary: Functional polyethylene is a specialty polymer with unique properties, and its direct synthesis through insertion copolymerization poses challenges but also offers potential environmental benefits and commercial opportunities. Incorporating renewable functional olefins and designing catalysts play key roles in advancing this field.
EUROPEAN POLYMER JOURNAL
(2021)
Review
Chemistry, Multidisciplinary
Anurag Mishra, Harshad R. Patil, Virendrakumar Gupta
Summary: In recent years, transition metal catalysts for propylene polymerization and copolymerization have shown significant progress, with a shift towards new generation catalysts including non-metallocene catalysts and late transition-metal catalysts. The focus is on the reactivity, selectivity, and resulting properties of the polymers, with an emphasis on the design of catalysts for different comonomers.
NEW JOURNAL OF CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Yu-Sheng Liu, Eva Harth
Summary: The introduction of m-xylyl substituents to alpha-diimine Pd-II catalyst promotes living ethylene polymerization, leading to high molecular weight polyethylene with low branching. The m-xylyl groups effectively block the axial sites of the catalytic center, preventing chain-transfer and easy accessibility of polar monomers, resulting in a living polymerization. Incorporating different acrylate block sequences can significantly modify the mechanical and chemical properties of block copolymers to be a hard plastic, elastomer, or semi-amorphous polymer.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Polymer Science
Kai Zhang, Yanli Dou, Yang Jiang, Zhen Zhang, Shihui Li, Dongmei Cui
Summary: The copolymerization of ethylene and butadiene using various scandium complexes led to the successful preparation of high molecular weight and structurally regular E/BD copolymers, showing excellent mechanical and physical properties surpassing traditional rubbers.
Article
Biochemistry & Molecular Biology
Ildar I. Salakhov, Tatiana B. Mikenas, Vladimir A. Zakharov, Valeriy G. Kozlov, Mikhail A. Matsko, Tatiana N. Suslova
Summary: This study investigates the catalytic performance of a titanium-magnesium catalyst in ethylene homopolymerization and ethylene/1-hexene copolymerization in the presence of chlorocyclohexane and hexachloro-p-xylene. The modified catalyst shows significantly increased activity, and the kinetic parameters and copolymer composition were determined.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Polymer Science
Shuyuan Yu, Chenggen Zhang, Fei Wang, Xinru Liang, Mengyao Yang, Mengyu An
Summary: Density functional theory (DFT) was used to investigate the promotion of B(C6F5)(3) as a ligand for titanium (or vanadium) catalysts in ethylene/1-hexene copolymerization reactions. The results showed that ethylene insertion into Ti-B (with B(C6F5)(3) as a ligand) was preferred over Ti-H, both thermodynamically and kinetically. In addition, V-B (with B(C6F5)(3) as a ligand) was found to be preferred over V-H for the entire ethylene/1-hexene copolymerization reaction, with higher reaction activity observed for V-B compared to Ti-B.
Article
Polymer Science
Miloud Bouyahyi, Lidia Jasinska-Walc, Rob Duchateau, Muhammad Naseem Akhtar, E. A. Jaseer, Rajesh Theravalappil, Nestor Garcia
Summary: In this study, the performance of different catalyst structures in polypropylene reactions was compared. It was found that zirconocenes and hafnocenes with substituted indenyl ligands had higher molecular weight capability, improved stereo-selectivity, and enhanced ability to incorporate functionalized comonomers. Additionally, a linear inversely proportional correlation between polymerization temperature and functionalized comonomer reactivity, copolymer molecular weight, and melting temperature was observed. Furthermore, the immobilization of the best performing catalyst onto silica failed to incorporate any functionalized comonomer.
Article
Chemistry, Multidisciplinary
Shi-Yu Chen, Ru-Chao Pan, Min Chen, Ye Liu, Changle Chen, Xiao-Bing Lu
Summary: Nonalternating copolymerization of olefin with carbon monoxide shows promise in improving processability and thermal stability of polyketones. The use of palladium coordinated diphosphazane monoxide with strong electron-donating groups enhances reactivity and ethylene incorporation, leading to lower melting temperatures and improved properties of the resulting materials. This study demonstrates the potential of cationic palladium complexes in achieving high reactivity and nonalternating degree in copolymerization reactions.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Materials Science, Multidisciplinary
Huafeng Shao, Xiaoxue Chen, Aihua He
Summary: A multi-block stereoregular copolymer of styrene and isoprene was successfully synthesized using a supported titanium Ziegler-Natta catalyst, showing higher reactivity of isoprene compared to styrene. Fractionation by n-hexane extraction revealed copolymers with varying lengths of trans-polyisoprene and isotactic polystyrene blocks. This work provides a novel approach for stereospecific copolymerization using traditional catalyst systems.
MATERIALS TODAY COMMUNICATIONS
(2022)
Article
Polymer Science
Ella F. Clark, Gabriele Kociok-Kohn, Matthew G. Davidson, Antoine Buchard
Summary: In this study, d-xylose 3,5-anyhydrosugar (d-Ox) was used in the ring-opening copolymerisation (ROCOP) with isothiocyanates to form alternating AB-type copolymers with imidothiocarbonate linkages. The use of an Al(iii)-based aminotrisphenolate complex as catalyst allowed the synthesis of thermally robust polymers with high glass-transition temperatures. The reactivity can be tailored by using an Al(iii) porphyrin complex as catalyst, enabling the formation of a non-polymerisable cyclic thionocarbamate byproduct. The polymers exhibited degradation under acidic and basic conditions, as well as photodegradation.
Article
Multidisciplinary Sciences
Wei Zhang, Sungmin Kim, Lennart Wahl, Rachit Khare, Lillian Hale, Jianzhi Hu, Donald M. Camaioni, Oliver Y. Gutierrez, Yue Liu, Johannes A. Lercher
Summary: We propose a unique approach to selectively upcycle polyolefin waste by utilizing a highly ionic reaction environment, which increases polymer reactivity and reduces energy required for breaking carbon-carbon bonds. By catalyzing endothermic cleavage and exothermic alkylation reactions, we are able to convert polyethylene and polypropylene to liquid isoalkanes at temperatures below 100 degrees C. This process offers a high yield conversion of unprocessed postconsumer items into high-quality liquid alkanes.
Article
Chemistry, Inorganic & Nuclear
Ruiyao Wu, Zhen Niu, Zhu Xia, Jianyun He, Chenxi Bai
Summary: Several vanadium complexes with 8-anilide-5,6,7-trihydroquinoline ligands were synthesized and characterized. These complexes showed high catalytic activity and thermal stability in ethylene polymerization and copolymerization reactions. The results suggest that the 8-anilide-5,6,7-trihydroquinoline ligands with fused rigid-flexible rings are beneficial for vanadium catalysts.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Multidisciplinary
Clement G. Collins Rice, Jean-Charles Buffet, Zoe R. Turner, Dermot O'Hare
Summary: Novel permethylindenyl-phenoxide (PHENI*) ansa-metallocene titanium complexes immobilized on solid supports show high catalytic activity for slurry-phase ethylene polymerization, producing substantially disentangled polyethylene with a weight-average molecular weight of 3.4 MDa.
CHEMICAL COMMUNICATIONS
(2021)
Article
Polymer Science
Lijuan Guo, Ryoji Makino, Daisuke Shimoyama, Joji Kadota, Hiroshi Hirano, Kotohiro Nomura
Summary: Ethylene-isoprene copolymers with higher glass-transition temperatures than those prepared by reported catalysts were synthesized using halftitanocene catalysts. The microstructural analysis revealed the presence of cyclopentane and cyclohexane units, formed by cyclization and ethylene insertion after isoprene. The Tg value in the copolymer increased with an increase in the isoprene content, depending on the catalyst employed. Due to their unique microstructure, the resulting copolymers exhibited promising tensile and elastic properties.
Article
Chemistry, Applied
Cheng Zhang, Yanshan Gao, Qinghua Yan, Qiang Wang
Review
Chemistry, Multidisciplinary
Shuyu Liang, Naveed Altaf, Liang Huang, Yanshan Gao, Qiang Wang
JOURNAL OF CO2 UTILIZATION
(2020)
Article
Engineering, Environmental
Tianshan Xue, Renna Li, Yanshan Gao, Qiang Wang
CHEMICAL ENGINEERING JOURNAL
(2020)
Review
Chemistry, Multidisciplinary
Jiazhen Chen, Yanshan Gao, Tobin J. Marks
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2020)
Editorial Material
Multidisciplinary Sciences
Yanshan Gao, Tobin J. Marks
Article
Chemistry, Multidisciplinary
Cole Carter, Yosi Kratish, Titel Jurca, Yanshan Gao, Tobin J. Marks
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2020)
Article
Chemistry, Physical
Jialong Zhang, Alexander H. Mason, Alessandro Motta, Laryssa G. Cesar, Yosi Kratish, Tracy L. Lohr, Jeffrey T. Miller, Yanshan Gao, Tobin J. Marks
Summary: Surface-bound organometallic catalysts offer a promising strategy to combine the advantages of homogeneous and heterogeneous catalysts for olefin polymerization, with potential variations in activity and comonomer selectivity achieved through ligand and support manipulation. The study highlights the importance of understanding the complex interactions between the catalyst, support, and reactants for optimizing catalytic performance.
Article
Chemistry, Multidisciplinary
Jianhong Zhao, Xing Zheng, Yan-Shan Gao, Jia Mao, Shu-Xiao Wu, Wu-Lin Yang, Xiaoyan Luo, Wei-Ping Deng
Summary: The study presents a [8+4] cycloaddition reaction using a secondary amine catalyst to produce indole and pyrrolidone annulated bicyclo[4.2.1]nonanes in a highly peri-, diastereo-, and enantioselective manner. This reaction, involving catalytically generated isobenzofulvenes, represents the first asymmetric version of high-order [8+4] cycloaddition.
CHINESE JOURNAL OF CHEMISTRY
(2021)
Article
Engineering, Industrial
Ying Cheng, Yanshan Gao, Lei Wang, Fei Tao, Qing-Guo Wang
Summary: This paper studies the operational robustness of the IIoT platform for Manufacturing Service Collaboration (MSC) and proposes a graph-based operational robustness analysis method. By modelling the IIoT platform operation network for MSC as an interdependent network structure, the effectiveness of MSC under uncertainty effects can be quantified.
INTERNATIONAL JOURNAL OF PRODUCTION RESEARCH
(2023)
Article
Multidisciplinary Sciences
Gang Ji, Zhou Chen, Xiao-Yan Wang, Xiao-Shan Ning, Chong-Jie Xu, Xing-Min Zhang, Wen-Jie Tao, Jun-Fang Li, Yanshan Gao, Qi Shen, Xiu-Li Sun, Hao-Yang Wang, Jun-Bo Zhao, Bo Zhang, Yin-Long Guo, Yanan Zhao, Jiajie Sun, Yi Luo, Yong Tang
Summary: The study presents a method for copolymerizing ethylene with protic monomers using multinuclear nickel catalysts, enabling functionalized polyolefins. Efficient direct copolymerization of ethylene with vinyl acetic acid by tetranuclear nickel complexes is achieved, with potential extension to other protic monomers. Insights from the study have led to the design of binuclear nickel catalysts that show high efficiency in copolymerization of ethylene with vinyl acetic acid or acrylic acid.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Physical
Rongrong Gui, Jiewen Xiao, Yanshan Gao, Yuran Li, Tingyu Zhu, Qiang Wang
Summary: In this study, a bifunctional catalyst Mn2Cu1Al1Ox was reported, which can simultaneously achieve selective catalytic reduction of NOx and catalytic oxidation of CO at low temperatures. By tuning the redox properties and surface oxygen vacancies, the optimized catalyst showed high conversions of both NOx and CO in the NH3-NO-CO-O2 system. The competition between NH3 and CO for the same active sites significantly influenced the catalytic performance, and the bifunctional catalyst enables both NH3-SCR and CO oxidation reactions to proceed simultaneously.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2022)
Article
Chemistry, Physical
Yanshan Gao, Matthew D. Christianson, Yang Wang, Marc P. Coons, Jiazhen Chen, Jialong Zhang, Steve Marshall, Tracy L. Lohr, Jerzy Klosin, Tobin J. Marks
Summary: The study investigates the role of binuclear diborate cocatalysts in olefin polymerization catalysis. By synthesizing different cocatalysts, the issue of poor solubility is addressed, enabling their efficient use in low-polarity solvents. The results demonstrate the significant impact of the cocatalysts on ethylene homopolymerization and copolymerization reactions in solvent systems of decreasing polarity.
Article
Chemistry, Physical
Xian-Ya Fang, Long Qin, Jiashuai Liu, Haonan Shi, Xiu-Li Sun, Xiaokang Kuang, Yanshan Gao, Yong Tang
Summary: In this study, a new class of oxazoline-amine zirconium complexes were synthesized and fully characterized. These complexes showed high activity in ethylene homopolymerization and ethylene/1-octene copolymerization.
MOLECULAR CATALYSIS
(2023)
Article
Chemistry, Physical
Bingxin Qu, Yanan Zhao, Ping Song, Yanshan Gao, You-Yun Zhou, Xiu-Li Sun, Qiang Fu, Xiaoshan Ning, Junfang Li, Xiaokang Kuang, Yong Tang
Summary: Chain walking is a unique process that allows control over polyolefin branch type, density, topology, branch stereochemistry, and more. By introducing a ring strained monomer like norbornene, the chain walking process can be perturbed to produce copolymers with unique microstructures.
Article
Chemistry, Physical
Yanshan Gao, Jiazhen Chen, Yang Wang, David B. Pickens, Alessandro Motta, Q. Jane Wang, Yip-Wah Chung, Tracy L. Lohr, Tobin J. Marks
