Molecular and kinetic design for the expanded control of molecular weights in the ring-opening metathesis polymerization of norbornene-substituted polyhedral oligomeric silsesquioxanes

2018 ◽  
Vol 9 (42) ◽  
pp. 5179-5189 ◽  
Author(s):  
Chang-Geun Chae ◽  
Yong-Guen Yu ◽  
Ho-Bin Seo ◽  
Myung-Jin Kim ◽  
Mallela Y. L. N. Kishore ◽  
...  
Keyword(s):  
Ring Opening ◽  
Kinetic Control ◽  
Polyhedral Oligomeric Silsesquioxanes ◽  
Ring Opening Metathesis Polymerization ◽  
Metathesis Polymerization ◽  
Molecular Weights

Rod-like POSS-containing polynorbornenes with high molecular weights were synthesized using ROMP with molecular and kinetic control.

scholarly journals Dinitrosyl rhenium complexes for ring-opening metathesis polymerization (ROMP)

2006 ◽  
Vol 78 (10) ◽  
pp. 1877-1887 ◽  
Author(s):  
Christian Manfred Frech ◽  
Olivier Blacque ◽  
Heinz Berke
Keyword(s):  
Phosphine Oxide ◽  
Ring Opening ◽  
Density Functional ◽  
Ring Opening Metathesis Polymerization ◽  
Olefinic Bond ◽  
Metathesis Polymerization ◽  
Molecular Weights ◽  
Cyclic Olefins ◽  
Phosphine Complexes ◽  
Unique Reaction

The treatment of benzene solutions of the cations [Re(NO)2(PR3)2][BArF4] (R = Cy and R = iPr; [BArF4] = tetrakis{3,5-bis(trifluoromethyl)phenyl}borate) with phenyldiazomethane afforded the moderately stable cationic rhenium(I) benzylidene dinitrosyl bis(trialkyl) phosphine complexes as [BArF4]- salts in good yields. The cationic rhenium dinitrosyl bisphosphine complexes catalyze the ring-opening metathesis polymerization (ROMP) of highly strained nonfunctionalized cyclic olefins to give polymers with relatively high polydispersity indices, high molecular weights, and Z configurations of the double bonds in the polymer chain backbones of over 80 %. The benzylidene derivatives are almost inactive in ROMP catalysis with norbornene and in olefin metathesis. NMR experiments gave first hints for the initial formation of carbene complexes when [Re(NO)2(PR3)2][BArF4] was treated with norbornene. The carbene formation is initiated by an unique reaction sequence where the cleavage of the strained olefinic bond starts with phosphine migration forming a cyclic ylid carbene complex. The [2+2] addition of a norbornene molecule to the Re=C bond leads to the rhenacyclobutane complex, which is expected to be converted into an iminate complex by attack of the ylid function onto one of the NNO atoms followed by Wittig-type phosphine oxide elimination. The formation of phosphine oxide was confirmed by NMR spectroscopy. This species is thought to drive the ROMP metathesis with alternating rhenacyclobutane formations and cycloreversions. The proposed mechanism is supported by density functional theory (DFT) calculations.

scholarly journals Application of olefin metathesis in the synthesis of functionalized polyhedral oligomeric silsesquioxanes (POSS) and POSS-containing polymeric materials

2019 ◽  
Vol 15 ◽  
pp. 310-332 ◽  
Author(s):  
Patrycja Żak ◽  
Cezary Pietraszuk
Keyword(s):  
Olefin Metathesis ◽  
Ring Opening ◽  
Polymeric Materials ◽  
Acyclic Diene Metathesis ◽  
Polyhedral Oligomeric Silsesquioxanes ◽  
Ring Opening Metathesis Polymerization ◽  
Metathesis Polymerization ◽  
Cross Metathesis ◽  
Terminal Olefins ◽  
Synthesized Materials

This mini-review summarizes the applications of olefin metathesis in synthesis and functionalization of polyhedral oligomeric silsesquioxanes (POSS) and POSS-containing polymeric materials. Three types of processes, i.e., cross metathesis (CM) of vinyl-substituted POSS with terminal olefins, acyclic diene metathesis (ADMET) copolymerization of divinyl-substituted POSS with α,ω-dienes and ring-opening metathesis polymerization (ROMP) of POSS-substituted norbornene (or other ROMP susceptible cycloolefins) are discussed. Emphasis was put on the synthetic and catalytic aspects rather than on the properties and applications of synthesized materials.

The Unsaturated Polyester Via Ring-Opening Metathesis Polymerization (ROMP) of ω-6-Hexadecenlactone

2018 ◽  
Vol 15 (4) ◽  
pp. 566-571 ◽  
Author(s):  
Araceli Martinez ◽  
Mikhail A. Tlenkopatchev ◽  
Selena Gutierrez
Keyword(s):  
Mechanical Properties ◽  
Ring Opening ◽  
Unsaturated Polyester ◽  
Thermal And Mechanical Properties ◽  
Ring Opening Metathesis Polymerization ◽  
Strain Measurements ◽  
Metathesis Polymerization ◽  
Molecular Weights ◽  
Wide Range ◽  
Percent Crystallinity

Background: Ring opening metathesis polymerization of lactones using alkylidene catalysts is an alternative to obtain unsaturated linear polyesters with remarkable thermal and mechanical properties. Also, these polyesters have properties of biodegradability which opens up a wide range of applications as environmentally friendly thermoplastics and biomaterials. Objective: This research aims to present one route to obtain an unsaturated linear polyester poly(ω-6- hexadecenlactone) via ring opening-metathesis polymerization of ω-6-hexadecenlactone using the rutheniumalkylidene [Ru(Cl)2(=CHPh)(PCy3)2] (I), [Ru(Cl2)(=CHPh)(1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene)( PCy3)] (II) and [Ru(Cl2)(=CH(o-isopropoxyphenylmethylene))(1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene)] (III) and the ruthenium-vinylidene [RuCl2(=C=CH(p-C6H4CF3))(PCy3)2] (IV) catalysts. Conclusion: The high number-average molecular weights of the poly(ω-6-hexadecenlactone) between Mn = 114,800-155,400 g/mol and yields ranging from 96 to 98 % can be achieved by II and III catalysts. The catalysts II and III with the N-heterocyclic carbene ligand showed superior activity and stability upon catalysts I and IV bearing PCy3 ligands. The hydrogenation of poly(ω-6-hexadecenlactone) using Wilkinson catalyst [RhCl(PPh3)3] was studied. The percent crystallinity of the unsaturated poly(ω-6-hexadecenlactone) was 31% with a melting temperature 47.60ºC. Stress-strain measurements of several poly(ω-6-hexadecenlactone) were determined.

Stereoretentive Ring-Opening Metathesis Polymerization to Access All-cis Poly(p-phenylene vinylene)s with Living Characteristics

2020 ◽  
Author(s):  
Ting-Wei Hsu ◽  
Cheoljae Kim ◽  
Quentin Michaudel
Keyword(s):  
Organic Material ◽  
Ring Opening ◽  
Diblock Copolymers ◽  
Conductive Polymer ◽  
Synthetic Methods ◽  
Phenylene Vinylene ◽  
Ring Opening Metathesis Polymerization ◽  
Metathesis Polymerization ◽  
Molecular Weights ◽  
Responsive Polymers

Poly(p-phenylene vinylene)s (PPVs), a staple of the conductive polymer family, consist of alternating alkene and phenyl groups in conjugation. The physical properties of this organic material are intimately linked to the cis/trans configuration of the alkene groups. While many synthetic methods afford PPVs with alltrans stereochemistry, very few deliver the all-cis congeners. We report herein the first synthesis of all-cis PPVs with living characteristics via stereoretentive ring-opening metathesis polymerization (ROMP). Exquisite catalyst control allows for the preparation of homopolymers or diblock copolymers with perfect stereoselectivity, narrow dispersities, and predictable molecular weights. All-cis PPVs can then serve as light-responsive polymers through clean photoisomerization of the stilbenoid units.

Stereoretentive Ring-Opening Metathesis Polymerization to Access All-cis Poly(p-phenylene vinylene)s with Living Characteristics

2020 ◽  
Author(s):  
Ting-Wei Hsu ◽  
Cheoljae Kim ◽  
Quentin Michaudel
Keyword(s):  
Organic Material ◽  
Ring Opening ◽  
Diblock Copolymers ◽  
Conductive Polymer ◽  
Synthetic Methods ◽  
Phenylene Vinylene ◽  
Ring Opening Metathesis Polymerization ◽  
Metathesis Polymerization ◽  
Molecular Weights ◽  
Responsive Polymers

Poly(p-phenylene vinylene)s (PPVs), a staple of the conductive polymer family, consist of alternating alkene and phenyl groups in conjugation. The physical properties of this organic material are intimately linked to the cis/trans configuration of the alkene groups. While many synthetic methods afford PPVs with alltrans stereochemistry, very few deliver the all-cis congeners. We report herein the first synthesis of all-cis PPVs with living characteristics via stereoretentive ring-opening metathesis polymerization (ROMP). Exquisite catalyst control allows for the preparation of homopolymers or diblock copolymers with perfect stereoselectivity, narrow dispersities, and predictable molecular weights. All-cis PPVs can then serve as light-responsive polymers through clean photoisomerization of the stilbenoid units.

Synthesis and Purification of Tunable High Tg Electro-Optical Polymers by Ring Opening Metathesis Polymerization

2011 ◽  
Author(s):  
Robert H. Lambeth ◽  
Joseph M. Dougherty ◽  
Joshua A. Orlicki ◽  
Adam M. Rawlett ◽  
Robert C. Hoffman ◽  
...  
Keyword(s):  
Ring Opening ◽  
Optical Polymers ◽  
Ring Opening Metathesis Polymerization ◽  
Metathesis Polymerization

Surface modification of carbon fibres using ring-opening metathesis polymerization

2021 ◽  
Vol 145 ◽  
pp. 106374
Author(s):  
David J. Hayne ◽  
Filip Stojcevski ◽  
Daniel B. Knorr ◽  
Ngon T. Tran ◽  
Luke C. Henderson
Keyword(s):  
Surface Modification ◽  
Ring Opening ◽  
Carbon Fibres ◽  
Ring Opening Metathesis Polymerization ◽  
Metathesis Polymerization
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