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Artigos de revistas sobre o tema "Coordinative Chain Transfer Polymerization"

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Publicado: 22 de junho de 2024

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1

Valente, Andreia, André Mortreux, Marc Visseaux e Philippe Zinck. "Coordinative Chain Transfer Polymerization". Chemical Reviews 113, n.º 5 (7 de fevereiro de 2013): 3836–57. http://dx.doi.org/10.1021/cr300289z.

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2

Baulu, Nicolas, Marie-Noëlle Poradowski, Ludmilla Verrieux, Julien Thuilliez, François Jean-Baptiste-dit-Dominique, Lionel Perrin, Franck D'Agosto e Christophe Boisson. "Design of selective divalent chain transfer agents for coordinative chain transfer polymerization of ethylene and its copolymerization with butadiene". Polymer Chemistry 13, n.º 14 (2022): 1970–77. http://dx.doi.org/10.1039/d2py00155a.

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3

Lee, Hyun Ju, Jun Won Baek, Tae Jin Kim, Hee Soo Park, Seung Hyun Moon, Kyung Lee Park, Sung Moon Bae, Jinil Park e Bun Yeoul Lee. "Synthesis of Long-Chain Branched Polyolefins by Coordinative Chain Transfer Polymerization". Macromolecules 52, n.º 23 (26 de novembro de 2019): 9311–20. http://dx.doi.org/10.1021/acs.macromol.9b01705.

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4

Ubaldo-Alarcón, Andrés, Florentino Soriano-Corral, Teresa Córdova, Iván Zapata-González e Ramón Díaz-de-León. "Terpene Coordinative Chain Transfer Polymerization: Understanding the Process through Kinetic Modeling". Polymers 14, n.º 12 (10 de junho de 2022): 2352. http://dx.doi.org/10.3390/polym14122352.

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The interest in the Coordinative Chain Transfer Polymerization (CCTP) of a family of naturally occurring hydrocarbon monomers, namely terpenes, for the production of high-performance rubbers is increasing year by year. In this work, the synthesis of poly(β-myrcene) via CCTP is introduced, using neodymium versatate (NdV3), diisobutylaluminum hydrade (DIBAH) as the catalytic system and dimethyldichlorosilane (Me2SiCl2) as the activator. A bimodal distribution in the GPC signal reveals the presence of two populations at low conversions, attributable to dormants (arising from reversible chain transfer reactions) and dead chains (arising from termination and irreversible chain transfer reactions); a unimodal distribution is generated at medium and high conversions, corresponding to the dominant species, the dormant chains. Additionally, a mathematical kinetic model was developed based on the Method of Moments to study a set of selected experiments: ([β-myrcene]0:[NdV3]0:[DIBAH]0:[Me2SiCl2]0 = 660:1:2:1, 885:1:2:1, and 533:1:2:1). In order to estimate the kinetic rate constant of the systems, a minimization of the sum of squared errors (SSE) between the model predicted values and the experimental measurements was carried out, resulting in an excellent fit. A set of the Arrhenius parameters were estimated for the ratio [β-myrcene]0:[NdV3]0:[DIBAH]0:[Me2SiCl2]0 = 660:1:2:1 in a temperature range between 50 to 70 °C. While the end-group functionality (EGF) was predominantly preserved as the ratio [β-myrcene]0:[NdV3]0 was decreased, higher catalytic activity was obtained with a high ratio.

5

Park, Kyung Lee, Jun Won Baek, Seung Hyun Moon, Sung Moon Bae, Jong Chul Lee, Junseong Lee, Myong Sun Jeong e Bun Yeoul Lee. "Preparation of Pyridylamido Hafnium Complexes for Coordinative Chain Transfer Polymerization". Polymers 12, n.º 5 (11 de maio de 2020): 1100. http://dx.doi.org/10.3390/polym12051100.

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The pyridylamido hafnium complex (I) discovered at Dow is a flagship catalyst among postmetallocenes, which are used in the polyolefin industry for PO-chain growth from a chain transfer agent, dialkylzinc. In the present work, with the aim to block a possible deactivation process in prototype compound I, the corresponding derivatives were prepared. A series of pyridylamido Hf complexes were prepared by replacing the 2,6-diisopropylphenylamido part in I with various 2,6-R2C6H3N-moieties (R = cycloheptyl, cyclohexyl, cyclopentyl, 3-pentyl, ethyl, or Ph) or by replacing 2-iPrC6H4C(H)- in I with the simple PhC(H)-moiety. The isopropyl substituent in the 2-iPrC6H4C(H)-moiety influences not only the geometry of the structures (revealed by X-ray crystallography), but also catalytic performance. In the complexes bearing the 2-iPrC6H4C(H)-moiety, the chelation framework forms a plane; however, this framework is distorted in the complexes containing the PhC(H)-moiety. The ability to incorporate α-olefin decreased upon replacing 2-iPrC6H4C(H)-with the PhC(H)-moiety. The complexes carrying the 2,6-di(cycloheptyl)phenylamido or 2,6-di(cyclohexyl)phenylamido moiety (replacing the 2,6-diisopropylphenylamido part in I) showed somewhat higher activity with greater longevity than did prototype catalyst I.

6

Wang, Feng, Heng Liu, YanMing Hu e XueQuan Zhang. "Lanthanide complexes mediated coordinative chain transfer polymerization of conjugated dienes". Science China Technological Sciences 61, n.º 9 (31 de julho de 2018): 1286–94. http://dx.doi.org/10.1007/s11431-018-9256-6.

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7

Göttker‐Schnetmann, Inigo, Philip Kenyon e Stefan Mecking. "Coordinative Chain Transfer Polymerization of Butadiene with Functionalized Aluminum Reagents". Angewandte Chemie International Edition 58, n.º 49 (2 de dezembro de 2019): 17777–81. http://dx.doi.org/10.1002/anie.201909843.

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8

Göttker‐Schnetmann, Inigo, Philip Kenyon e Stefan Mecking. "Coordinative Chain Transfer Polymerization of Butadiene with Functionalized Aluminum Reagents". Angewandte Chemie 131, n.º 49 (24 de outubro de 2019): 17941–45. http://dx.doi.org/10.1002/ange.201909843.

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9

Wallace, Mark A., Aaron A. Burkey e Lawrence R. Sita. "Phenyl-Terminated Polyolefins via Living Coordinative Chain Transfer Polymerization with ZnPh2 as a Chain Transfer Agent". ACS Catalysis 11, n.º 16 (2 de agosto de 2021): 10170–78. http://dx.doi.org/10.1021/acscatal.1c02038.

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10

Hashmi, Obaid H., Marc Visseaux e Yohan Champouret. "Evidence of coordinative chain transfer polymerization of isoprene using iron iminopyridine/ZnEt2 catalytic systems". Polymer Chemistry 12, n.º 32 (2021): 4626–31. http://dx.doi.org/10.1039/d1py00433f.

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11

Ding, Aiwu, Liang Fang, Chunyu Zhang, Heng Liu, Xuequan Zhang e Jianhe Liao. "Neodymium-Mediated Coordinative Chain Transfer Polymerization of Isoprene in the Presence of External Donors". Molecules 28, n.º 21 (31 de outubro de 2023): 7364. http://dx.doi.org/10.3390/molecules28217364.

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Nd-based polydiene elastomers, including NdIR and NdBR, are regarded as indispensable key raw materials in preparing green tires with excellent performance capabilities, but their wide application is still limited by the relative higher cost of Nd precatalysts. Nd-mediated coordinative chain transfer polymerization (CCTP) of diene provides an effective strategy to reduce the precatalyst cost, because this method involves very high atom economy, i.e., each Nd molecule can generate multiple polymer chains. Nevertheless, all possible factors that could influence such CCTP behaviors are still mostly unexplored to date. In this report, the basic chemistry on the influence of external donors on the overall CCTP behaviors of isoprene was established for the first time. It was found that increasing the amount of external donors had a negative influence on the chain transfer efficiencies, resulting in gradually decreasing atom economies. Catalyst addition order studies revealed that the coordination of donors with cationic Nd active species, rather than alkylaluminium CTAs, contributed mostly to such decreased efficiencies. Moreover, it was found that when the ratio of donors and Nd compounds was higher than 1.0, the CCTP behaviors were corrupted, resulting in polymers with broad distributions, as well as resulting in low atom economies; nevertheless, when the ratio was lower than 0.5, the system still displayed CCTP characteristics, implying that the critical ratio for maintaining the CCTP was 0.5. Additionally, when such a ratio was 0.01, the high atom economy was almost the same as donor-free CCTP systems. Detailed kinetic studies at such a ratio demonstrated that the donor-contained system proceeded in a well-controlled manner, as concluded from the good linear relationship between the Mn of the PIps against the polymer yields, as well as the good linearity between the Mn against the (IP)/(Nd) ratios. Such maintained CCTP properties also allowed for seeding two-step polymerizations to prepare diblock copolymers with precisely controlled molecular weights. Expanding the types of donors to more phosphine, oxygen, and nitrogen containing compounds showed that they also affected the CCTP behaviors depending on their steric and electronic properties.

12

Hustad, Phillip D., Roger L. Kuhlman, Daniel J. Arriola, Edmund M. Carnahan e Timothy T. Wenzel. "Continuous Production of Ethylene-Based Diblock Copolymers Using Coordinative Chain Transfer Polymerization". Macromolecules 40, n.º 20 (outubro de 2007): 7061–64. http://dx.doi.org/10.1021/ma0717791.

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13

Tang, Zhengwei, Aimin Liang, Handong Liang, Jiangwei Zhao, Lin Xu e Jie Zhang. "Reversible Coordinative Chain Transfer Polymerization of Butadiene Using a Neodymium Phosphonate Catalyst". Macromolecular Research 27, n.º 8 (30 de março de 2019): 789–94. http://dx.doi.org/10.1007/s13233-019-7105-5.

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14

Zinck, Philippe. "Tuning polyolefins and polydienes microstructure and architecture via coordinative chain transfer polymerization". Polymer International 61, n.º 1 (3 de outubro de 2011): 2–5. http://dx.doi.org/10.1002/pi.3175.

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15

Nzahou Ottou, Winnie, Sébastien Norsic, Islem Belaid, Christophe Boisson e Franck D’Agosto. "Amino End-Functionalized Polyethylenes and Corresponding Telechelics by Coordinative Chain Transfer Polymerization". Macromolecules 50, n.º 21 (17 de outubro de 2017): 8372–77. http://dx.doi.org/10.1021/acs.macromol.7b01396.

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16

Córdova, Teresa, Francisco Javier Enríquez-Medrano, Eduardo Martínez Cartagena, Arnulfo Banda Villanueva, Luis Valencia, Edgar Nazareo Cabrera Álvarez, Ricardo López González e Ramón Díaz-de-León. "Coordinative Chain Transfer Polymerization of Sustainable Terpene Monomers Using a Neodymium-Based Catalyst System". Polymers 14, n.º 14 (17 de julho de 2022): 2907. http://dx.doi.org/10.3390/polym14142907.

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The present investigation involves the coordinative chain transfer polymerization (CCTP) of biobased terpenes in order to obtain sustainable polymers from myrcene (My) and farnesene (Fa), using the ternary Ziegler–Natta catalyst system comprising [NdV3]/[Al(i-Bu)2H]/[Me2SiCl2] and Al(i-Bu)2H, which acts as cocatalyst and chain transfer agent (CTA). The polymers were produced with a yield above 85% according to the monomeric consumption at the end of the reaction, and the kinetic examination revealed that the catalyst system proceeded with a reversible chain transfer mechanism in the presence of 15–30 equiv. of CTA. The resulting polyterpenes showed narrow molecular weight distributions (Mw/Mn = 1.4–2.5) and a high percent of 1,4-cis microstructure in the presence of 1 equiv. of Me2SiCl2, having control of the molecular weight distribution in Ziegler–Natta catalytic systems that maintain a high generation of 1,4-cis microstructure.

17

Wang, Feng, Bo Dong, Heng Liu, Jun Guo, Wenjie Zheng, Chunyu Zhang, Liping Zhao, Chenxi Bai, Yanming Hu e Xuequan Zhang. "Synthesis of Block Copolymers Containing Polybutadiene Segments by Combination of Coordinative Chain Transfer Polymerization, Ring-Opening Polymerization, and Atom Transfer Radical Polymerization". Macromolecular Chemistry and Physics 216, n.º 3 (29 de novembro de 2014): 321–28. http://dx.doi.org/10.1002/macp.201400465.

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18

Wei, Jia, Wonseok Hwang, Wei Zhang e Lawrence R. Sita. "Dinuclear Bis-Propagators for the Stereoselective Living Coordinative Chain Transfer Polymerization of Propene". Journal of the American Chemical Society 135, n.º 6 (29 de janeiro de 2013): 2132–35. http://dx.doi.org/10.1021/ja312463f.

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19

Zinck, Philippe, Andreia Valente, Fanny Bonnet, Ana Violante, AndrÃ© Mortreux, Marc Visseaux, Simona Ilinca, Rob Duchateau e Pascal Roussel. "Reversible coordinative chain transfer polymerization of styrene by rare earth borohydrides, chlorides/dialkylmagnesium systems". Journal of Polymer Science Part A: Polymer Chemistry 48, n.º 4 (15 de fevereiro de 2010): 802–14. http://dx.doi.org/10.1002/pola.23828.

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20

Ribeiro, Rodolfo, Rui Ruivo, Hajar Nsiri, Sébastien Norsic, Franck D’Agosto, Lionel Perrin e Christophe Boisson. "Deciphering the Mechanism of Coordinative Chain Transfer Polymerization of Ethylene Using Neodymocene Catalysts and Dialkylmagnesium". ACS Catalysis 6, n.º 2 (6 de janeiro de 2016): 851–60. http://dx.doi.org/10.1021/acscatal.5b02316.

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21

Sarazin, Yann, Pierre de Frémont, Liana Annunziata, Michel Duc e Jean-François Carpentier. "Syndio- and Isoselective Coordinative Chain Transfer Polymerization of Styrene Promoted by ansa-Lanthanidocene/ Dialkylmagnesium Systems". Advanced Synthesis & Catalysis 353, n.º 8 (maio de 2011): 1367–74. http://dx.doi.org/10.1002/adsc.201100059.

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22

Belaid, Islem, Marie-Noëlle Poradowski, Samira Bouaouli, Julien Thuilliez, Lionel Perrin, Franck D’Agosto e Christophe Boisson. "Dialkenylmagnesium Compounds in Coordinative Chain Transfer Polymerization of Ethylene. Reversible Chain Transfer Agents and Tools To Probe Catalyst Selectivities toward Ring Formation". Organometallics 37, n.º 10 (9 de maio de 2018): 1546–54. http://dx.doi.org/10.1021/acs.organomet.8b00127.

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23

Lin, Fei, Zhaohe Liu, Meiyan Wang, Bo Liu, Shihui Li e Dongmei Cui. "Chain Transfer to Toluene in Styrene Coordination Polymerization". Angewandte Chemie 132, n.º 11 (9 de março de 2020): 4354–58. http://dx.doi.org/10.1002/ange.201914603.

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24

Lin, Fei, Zhaohe Liu, Meiyan Wang, Bo Liu, Shihui Li e Dongmei Cui. "Chain Transfer to Toluene in Styrene Coordination Polymerization". Angewandte Chemie International Edition 59, n.º 11 (3 de fevereiro de 2020): 4324–28. http://dx.doi.org/10.1002/anie.201914603.

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25

D'Agosto, Franck, e Christophe Boisson. "A RAFT Analogue Olefin Polymerization Technique Using Coordination Chemistry". Australian Journal of Chemistry 63, n.º 8 (2010): 1155. http://dx.doi.org/10.1071/ch10098.

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The present paper highlights analogies between one of the most efficient control radical polymerization techniques namely the reversible addition–fragmentation chain transfer process, and the catalyzed polyethylene chain growth, the only technique that can controlled olefins polymerization through coordination chemistry under catalytic conditions.

26

Kim, Tae Jin, Jun Won Baek, Seung Hyun Moon, Hyun Ju Lee, Kyung Lee Park, Sung Moon Bae, Jong Chul Lee, Pyung Cheon Lee e Bun Yeoul Lee. "Polystyrene Chain Growth Initiated from Dialkylzinc for Synthesis of Polyolefin-Polystyrene Block Copolymers". Polymers 12, n.º 3 (2 de março de 2020): 537. http://dx.doi.org/10.3390/polym12030537.

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Polyolefins (POs) are the most abundant polymers. However, synthesis of PO-based block copolymers has only rarely been achieved. We aimed to synthesize various PO-based block copolymers by coordinative chain transfer polymerization (CCTP) followed by anionic polymerization in one-pot via conversion of the CCTP product (polyolefinyl)2Zn to polyolefinyl-Li. The addition of 2 equiv t-BuLi to (1-octyl)2Zn (a model compound of (polyolefinyl)2Zn) and selective removal or decomposition of (tBu)2Zn by evacuation or heating at 130 °C afforded 1-octyl-Li. Attempts to convert (polyolefinyl)2Zn to polyolefinyl-Li were unsuccessful. However, polystyrene (PS) chains were efficiently grown from (polyolefinyl)2Zn; the addition of styrene monomers after treatment with t-BuLi and pentamethyldiethylenetriamine (PMDTA) in the presence of residual olefin monomers afforded PO-block-PSs. Organolithium species that might be generated in the pot of t-BuLi, PMDTA, and olefin monomers, i.e., [Me2NCH2CH2N(Me)CH2CH2N(Me)CH2Li, Me2NCH2CH2N(Me)Li·(PMDTA), pentylallyl-Li⋅(PMDTA)], as well as PhLi⋅(PMDTA), were screened as initiators to grow PS chains from (1-hexyl)2Zn, as well as from (polyolefinyl)2Zn. Pentylallyl-Li⋅(PMDTA) was the best initiator. The Mn values increased substantially after the styrene polymerization with some generation of homo-PSs (27–29%). The Mn values of the extracted homo-PS suggested that PS chains were grown mainly from polyolefinyl groups in [(polyolefinyl)2(pentylallyl)Zn]−[Li⋅(PMDTA)]+ formed by pentylallyl-Li⋅(PMDTA) acting onto (polyolefinyl)2Zn.

27

Wallace, Mark A., e Lawrence R. Sita. "Multi-State Living Degenerative and Chain Transfer Coordinative Polymerization of α-Olefins via Sub-Stoichiometric Activation". ACS Catalysis 11, n.º 15 (19 de julho de 2021): 9754–60. http://dx.doi.org/10.1021/acscatal.1c02120.

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28

Wang, Feng, Chun-yu Zhang, Yan-ming Hu, Xiang-yu Jia, Chen-xi Bai e Xue-quan Zhang. "Reversible coordinative chain transfer polymerization of isoprene and copolymerization with ε-caprolactone by neodymium-based catalyst". Polymer 53, n.º 26 (dezembro de 2012): 6027–32. http://dx.doi.org/10.1016/j.polymer.2012.10.044.

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29

Cueny, Eric S., Lawrence R. Sita e Clark R. Landis. "Quantitative Validation of the Living Coordinative Chain-Transfer Polymerization of 1-Hexene Using Chromophore Quench Labeling". Macromolecules 53, n.º 14 (15 de julho de 2020): 5816–25. http://dx.doi.org/10.1021/acs.macromol.0c00552.

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30

Minyaev, Mikhail E., Pavel D. Komarov, Dmitrii M. Roitershtein, Konstantin A. Lyssenko, Ilya E. Nifant’ev, Lada N. Puntus, Evgenia A. Varaksina, Roman S. Borisov, Viktor P. Dyadchenko e Pavel V. Ivchenko. "Aryloxy Alkyl Magnesium versus Dialkyl Magnesium in the Lanthanidocene-Catalyzed Coordinative Chain Transfer Polymerization of Ethylene". Organometallics 38, n.º 15 (18 de julho de 2019): 2892–901. http://dx.doi.org/10.1021/acs.organomet.9b00243.

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31

Fan, Changliang, Chenxi Bai, Hongguang Cai, Quanquan Dai, Xuequan Zhang e Fosong Wang. "Preparation of high cis-1,4 polyisoprene with narrow molecular weight distribution via coordinative chain transfer polymerization". Journal of Polymer Science Part A: Polymer Chemistry 48, n.º 21 (7 de setembro de 2010): 4768–74. http://dx.doi.org/10.1002/pola.24268.

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32

Maddah, Yasaman, Saeid Ahmadjo, Seyed Mohammad Mahdi Mortazavi, Farhad Sharif, Davood Hassanian-Moghaddam e Mostafa Ahmadi. "Control over Branching Topology by Introducing a Dual Catalytic System in Coordinative Chain Transfer Polymerization of Olefins". Macromolecules 53, n.º 11 (14 de maio de 2020): 4312–22. http://dx.doi.org/10.1021/acs.macromol.0c00358.

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33

Infante-Martínez, Ramiro, Enrique Saldívar-Guerra, Odilia Pérez-Camacho, Maricela García-Zamora e Víctor Comparán-Padilla. "Prediction of molecular weight distribution in chain growth polymerizations". MRS Proceedings 1767 (2015): 87–91. http://dx.doi.org/10.1557/opl.2015.231.

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ABSTRACTThis work presents results on the prediction of the molecular weight distributions (MWD) of chain growth polymerization using conventional software and hardware tools. The investigation focuses on two kinds of polymerization processes: free radical batch and continuous polymerization processes with application to low density polyethylene synthesis (LDPE); and coordination polymerization via metallocenes with application to high density polyethylene synthesis (HDPE). For both processes, kinetic models, consisting of sets of differential equations describing the dynamic behavior of all the chemical species in the reaction media, are presented. From these sets is possible to obtain the molecular weight distribution of the polymer1,2,4Strategies for the simulation of the polymerization models were developed and results of these simulations are presented. On the free radical polymerization case, the next results are highlighted: i) It was confirmed that the chain transfer to polymer step produces strong asymmetries on the MWD as well as a high polydispersity index; ii) It’s possible to calculate the MWD in the CSTR process through a simulation strategy that permits the decoupling of the live and dead chains populations. On the metallocene polymerization case, it was demonstrated that the coordination standard model represents well the system experimentally studied and it can be employed to directly calculate the molecular weight distribution.These results confirm the idea that the complete MWD can be directly calculated with conventional hardware and software tools.

34

Baek, Jun Won, Su Jin Kwon, Hyun Ju Lee, Tae Jin Kim, Ji Yeon Ryu, Junseong Lee, Eun Ji Shin, Ki Soo Lee e Bun Yeoul Lee. "Preparation of Half- and Post-Metallocene Hafnium Complexes with Tetrahydroquinoline and Tetrahydrophenanthroline Frameworks for Olefin Polymerization". Polymers 11, n.º 7 (27 de junho de 2019): 1093. http://dx.doi.org/10.3390/polym11071093.

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Hafnium complexes have drawn attention for their application as post-metallocene catalysts with unique performance in olefin polymerization. In this work, a series of half-metallocene HfMe2 complexes, bearing a tetrahydroquinoline framework, as well as a series of [Namido,N,Caryl]HfMe2-type post-metallocene complexes, bearing a tetrahydrophenanthroline framework, were prepared; the structures of the prepared Hf complexes were unambiguously confirmed by X-ray crystallography. When the prepared complexes were reacted with anhydrous [(C18H37)2N(H)Me]+[B(C6F5)4]−, desired ion-pair complexes, in which (C18H37)2NMe coordinated to the Hf center, were cleanly afforded. The activated complexes generated from the half-metallocene complexes were inactive for the copolymerization of ethylene/propylene, while those generated from post-metallocene complexes were active. Complex bearing bulky isopropyl substituents (12) exhibited the highest activity. However, the activity was approximately half that of the prototype pyridylamido-Hf Dow catalyst. The comonomer incorporation capability was also inferior to that of the pyridylamido-Hf Dow catalyst. However, 12 performed well in the coordinative chain transfer polymerization performed in the presence of (octyl)2Zn, converting all the fed (octyl)2Zn to (polyolefinyl)2Zn with controlled lengths of the polyolefinyl chain.

35

Liu, Zhaohe, Changguang Yao, Chunji Wu, Zhongfu Zhao e Dongmei Cui. "Additive-Triggered Chain Transfer to a Solvent in Coordination Polymerization". Macromolecules 53, n.º 4 (3 de fevereiro de 2020): 1205–11. http://dx.doi.org/10.1021/acs.macromol.9b02495.

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36

Jamali, Farhad, Davood Hassanian-Moghaddam, Saeid Ahmadjo, Seyed Mohammad Mahdi Mortazavi, Yasaman Maddah e Mostafa Ahmadi. "Amphiphilic olefin block copolymers synthesized by successive coordinative chain transfer and ring-opening polymerizations". European Polymer Journal 169 (abril de 2022): 111142. http://dx.doi.org/10.1016/j.eurpolymj.2022.111142.

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Hassanian-Moghaddam, Davood, Yasaman Maddah, Saeid Ahmadjo, Seyed Mohammad Mahdi Mortazavi, Farhad Sharif e Mostafa Ahmadi. "Mechanistic study on the metallocene-based tandem catalytic coordinative chain transfer polymerization for the synthesis of highly branched polyolefins". European Polymer Journal 152 (junho de 2021): 110454. http://dx.doi.org/10.1016/j.eurpolymj.2021.110454.

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38

Valente, Andreia, Philippe Zinck, Marta J. Vitorino, A. Mortreux e M. Visseaux. "Rare earths/main group metal alkyls catalytic systems for the 1,4-trans stereoselective coordinative chain transfer polymerization of isoprene". Journal of Polymer Science Part A: Polymer Chemistry 48, n.º 21 (8 de setembro de 2010): 4640–47. http://dx.doi.org/10.1002/pola.24225.

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39

Mohammadi, Yousef, Mostafa Ahmadi, Mohammad Reza Saeb, Mohammad Mehdi Khorasani, Pianpian Yang e Florian J. Stadler. "A Detailed Model on Kinetics and Microstructure Evolution during Copolymerization of Ethylene and 1-Octene: From Coordinative Chain Transfer to Chain Shuttling Polymerization". Macromolecules 47, n.º 14 (30 de junho de 2014): 4778–89. http://dx.doi.org/10.1021/ma500874h.

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40

Zhang, Wei, Jia Wei e Lawrence R. Sita. "Living Coordinative Chain-Transfer Polymerization and Copolymerization of Ethene, α-Olefins, and α,ω-Nonconjugated Dienes using Dialkylzinc as “Surrogate” Chain-Growth Sites". Macromolecules 41, n.º 21 (11 de novembro de 2008): 7829–33. http://dx.doi.org/10.1021/ma801962v.

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41

Gibson, Vernon C., Rachel K. O'Reilly, Duncan F. Wass, Andrew J. P. White e David J. Williams. "Polymerization of Methyl Methacrylate Using Four-Coordinate (α-Diimine)iron Catalysts: Atom Transfer Radical Polymerization vs Catalytic Chain Transfer". Macromolecules 36, n.º 8 (abril de 2003): 2591–93. http://dx.doi.org/10.1021/ma034046z.

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42

Jinjin Wang, Jinjin Wang, Wangbin Chen Wangbin Chen, Manlin Zhang Manlin Zhang, Bin Pan Bin Pan, Xiaorong Wang Xiaorong Wang e Bin Wang Bin Wang. "Simulation and Analysis of Propylene Coordination Polymerization Process Based on Aspen (polymer) plus". Journal of the chemical society of pakistan 42, n.º 1 (2020): 62. http://dx.doi.org/10.52568/000615.

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Resumo:

Based on the industrial conditions of coordination polymerization of polypropylene, Polymer plus was used to simulate and analyze the coordination process of propylene. The effects of the amount of propane, main catalyst (TiCl4), chain transfer agent (hydrogen), shielding gas (nitrogen), and monomer (propylene) on the number average degree of polymerization (DPN), the weight average degree of polymerization (DPW), the number average molecular weight (MWN), the weight average molecular weight (MWW), the polydispersity index (PDI), and the throughput of polypropylene were explored to guide actual production in this paper. Through analysis, the polymerization degree and molecular weight of polypropylene could be adjusted by hydrogen in actual production. The monomer (propylene) should be purified as much as possible to reduce the feed amount of propane. The increase of the propylene contributed to the molecular weight and polymerization degree of the product. The increase in the nitrogen feed amount had no effect on the product performance index. The feed amount of nitrogen could be adjusted as needed according to the actual equipment specifications. The catalyst has the greatest influence on the comprehensive performance index of the product, thus the amount of main catalyst TiCl4 must be strictly controlled.

43

Jinjin Wang, Jinjin Wang, Wangbin Chen Wangbin Chen, Manlin Zhang Manlin Zhang, Bin Pan Bin Pan, Xiaorong Wang Xiaorong Wang e Bin Wang Bin Wang. "Simulation and Analysis of Propylene Coordination Polymerization Process Based on Aspen (polymer) plus". Journal of the chemical society of pakistan 42, n.º 1 (2020): 62. http://dx.doi.org/10.52568/000615/jcsp/42.01.2020.

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Resumo:

Based on the industrial conditions of coordination polymerization of polypropylene, Polymer plus was used to simulate and analyze the coordination process of propylene. The effects of the amount of propane, main catalyst (TiCl4), chain transfer agent (hydrogen), shielding gas (nitrogen), and monomer (propylene) on the number average degree of polymerization (DPN), the weight average degree of polymerization (DPW), the number average molecular weight (MWN), the weight average molecular weight (MWW), the polydispersity index (PDI), and the throughput of polypropylene were explored to guide actual production in this paper. Through analysis, the polymerization degree and molecular weight of polypropylene could be adjusted by hydrogen in actual production. The monomer (propylene) should be purified as much as possible to reduce the feed amount of propane. The increase of the propylene contributed to the molecular weight and polymerization degree of the product. The increase in the nitrogen feed amount had no effect on the product performance index. The feed amount of nitrogen could be adjusted as needed according to the actual equipment specifications. The catalyst has the greatest influence on the comprehensive performance index of the product, thus the amount of main catalyst TiCl4 must be strictly controlled.

44

Santoro, Orlando, Lorenzo Piola, Karl Mc Cabe, Olivier Lhost, Katty Den Dauw, Aurélien Vantomme, Alexandre Welle, Laurent Maron, Jean-François Carpentier e Evgueni Kirillov. "Long-Chain Branched Polyethylene via Coordinative Tandem Insertion and Chain-Transfer Polymerization Using rac-{EBTHI}ZrCl2/MAO/Al–alkenyl Combinations: An Experimental and Theoretical Study". Macromolecules 53, n.º 20 (8 de outubro de 2020): 8847–57. http://dx.doi.org/10.1021/acs.macromol.0c01671.

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45

Wallace, Mark A., e Lawrence R. Sita. "Temporal Control over Two‐ and Three‐State Living Coordinative Chain Transfer Polymerization for Modulating the Molecular Weight Distribution Profile of Polyolefins". Angewandte Chemie 133, n.º 36 (3 de agosto de 2021): 19823–30. http://dx.doi.org/10.1002/ange.202105937.

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46

Wallace, Mark A., e Lawrence R. Sita. "Temporal Control over Two‐ and Three‐State Living Coordinative Chain Transfer Polymerization for Modulating the Molecular Weight Distribution Profile of Polyolefins". Angewandte Chemie International Edition 60, n.º 36 (3 de agosto de 2021): 19671–78. http://dx.doi.org/10.1002/anie.202105937.

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47

Elkin, Tatyana, Stacy Copp, Ryan Hamblin, Jennifer Martinez, Gabriel Montaño e Reginaldo Rocha. "Synthesis of Terpyridine-Terminated Amphiphilic Block Copolymers and Their Self-Assembly into Metallo-Polymer Nanovesicles". Materials 12, n.º 4 (17 de fevereiro de 2019): 601. http://dx.doi.org/10.3390/ma12040601.

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Polystyrene-b-polyethylene glycol (PS-b-PEG) amphiphilic block copolymers featuring a terminal tridentate N,N,N-ligand (terpyridine) were synthesized for the first time through an efficient route. In this approach, telechelic chain-end modified polystyrenes were produced via reversible addition-fragmentation chain-transfer (RAFT) polymerization by using terpyridine trithiocarbonate as the chain-transfer agent, after which the hydrophilic polyethylene glycol (PEG) block was incorporated into the hydrophobic polystyrene (PS) block in high yields via a thiol-ene process. Following metal-coordination with Mn2+, Fe2+, Ni2+, and Zn2+, the resulting metallo-polymers were self-assembled into spherical, vesicular nanostructures, as characterized by dynamic light scattering and transmission electron microscopy (TEM) imaging.

48

You, Qian Qian, e Pu Yu Zhang. "Synthesis of Copper Complexes of Poly [2-(dimethylamino ethyl methacrylate)-B-Poly (oligo (ethylene glycol) monomethylether methacrylate-B-Poly [2-(dimethylamino ethyl methacrylate)". Advanced Materials Research 668 (março de 2013): 145–48. http://dx.doi.org/10.4028/www.scientific.net/amr.668.145.

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Three different ratios of double hydrophilic block copolymers poly [2-(dimethylamino) ethyl methacrylate]-b-poly(oligo(ethylene oxide) monomethyl ether methacrylate)-b-poly [2-(dimethylamino) ethyl methacrylate] (PDMAEMA-b-POEOMA-b-PDMAEMA) were synthesized by reversible addition fragmentation chain-transfer polymerization (RAFT), which was one of the controlled/living radical polymerization. The chain structure and component of such copolymers were characterized by spectroscopic studies (FTIR, 1H NMR). The interaction of PDMAEMA-b-POEOMA-b-PDMAEMA copolymers with copper sulfate and copper chloride solution was studied. It was found that the anion SO42-, Cl-1 could have an effect on the structure and coordination of the Cu(II) complexes, which were confirmed by FTIR and scanning electron micrographs (SEM).

49

Ji, Xianzhong, Shufen Pang, Yuliang Li e Jun Ouyang. "CHAIN TRANSFER REACTIONS IN THE POLYMERIZATION OF BUTADIENE WITH RARE EARTH COORDINATION CATALYST". Chinese Journal of Applied Chemistry 2, n.º 4 (1 de dezembro de 1985): 16–19. http://dx.doi.org/10.3724/j.issn.1000-0518.1985.4.16.

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50

Ji, Xianzhong, Shufen Pang, Yuliang Li e Jun Ouyang. "CHAIN TRANSFER REACTIONS IN THE POLYMERIZATION OF BUTADIENE WITH RARE EARTH COORDINATION CATALYST". Chinese Journal of Applied Chemistry 2, n.º 4 (1 de dezembro de 1985): 16–19. http://dx.doi.org/10.3724/j.issn.1000-0518.1985.4.1619.

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