Catalyst-Transfer Condensation Polymerization for the Synthesis of Well-Defined Polythiophene with Hydrophilic Side Chain and of Diblock Copolythiophene with Hydrophilic and Hydrophobic Side Chains

2007 ◽  
Vol 19 (5-6) ◽  
pp. 684-699 ◽  
Author(s):  
Tsutomu Yokozawa ◽  
Isao Adachi ◽  
Ryo Miyakoshi ◽  
Akihiro Yokoyama
Keyword(s):  
Block Copolymer ◽  
Feed Ratio ◽  
Ni Catalyst ◽  
Chain Growth ◽  
Condensation Polymerization ◽  
Block Copolymerization ◽  
Ni Catalysts ◽  
Linear Relationships ◽  
A Chain ◽  
Polymerization Method

Chain-growth condensation polymerization of 2-bromo-5-chloromagnesio-3-[2-(2-metho-xyethoxy)ethoxy]methylthiophene (2) with Ni catalysts was studied, and the block copolymer of poly2 and poly(3-hexylthiophene) was synthesized by this polymerization method. The polymerization of 2 depended on the ligands of the Ni catalyst, and poly2 with the lowest polydispersity was obtained when 1,2-bis(diphenylphosphino)ethane (dppe) was used as the ligand. The linear relationships between the conversion of 2 and Mn of the polymer and between the feed ratio of 2 to the Ni catalyst and Mn of the polymer indicate that this polymerization proceeds in a chain-growth polymerization manner via a catalyst-transfer condensation polymerization mechanism. The block copolymerization of 2 and 2-bromo-5-chloromagnesio-3-hexylthiophene (1) was then carried out in four ways by changing the order of polymerization of the two monomers and the catalysts. It turned out that the block copolymer was obtained without the formation of the homopolymers by the polymerization of 1 with Ni(dppe)Cl2 or Ni(dppp)Cl2 (dppp = 1,2-bis(diphenylphosphino)propane), followed by the postpolymerization of 2. Of the two catalysts, Ni(dppe)Cl2 resulted in narrower polydispersity of the block copolymer.

Catalyst-transfer condensation polymerization for precision synthesis of π-conjugated polymers

2012 ◽  
Vol 85 (3) ◽  
pp. 573-587 ◽  
Author(s):  
Tsutomu Yokozawa ◽  
Yutaka Nanashima ◽  
Haruhiko Kohno ◽  
Ryosuke Suzuki ◽  
Masataka Nojima ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Conjugated Polymers ◽  
Ni Catalyst ◽  
Condensation Polymerization ◽  
End Groups ◽  
Precision Synthesis ◽  
Polymerization Method ◽  
Low Solubility ◽  
End Group ◽  
Coupling Polymerization

Catalyst-transfer condensation polymerization, in which the catalyst activates the polymer end-group, followed by reaction with the monomer and transfer of the catalyst to the elongated polymer end-group, has made it feasible to control the molecular weight, polydispersity, and end-groups of π-conjugated polymers. In this paper, our recent progress of Kumada–Tamao Ni catalyst-transfer coupling polymerization and Suzuki–Miyaura Pd catalyst-transfer coupling polymerization is described. In the former polymerization method, the polymerization of Grignard pyridine monomers was investigated for the synthesis of well-defined n-type π-conjugated polymers. Para-type pyridine monomer, 3-alkoxy-2-bromo-5-chloromagnesiopyridine, afforded poly(pyridine-2,5-diyl) with low solubility in the reaction solvent, whereas meta-type pyridine monomer, 2-alkoxy-5-bromo-3-chloromagnesio-pyridine, yielded soluble poly(pyridine-3,5-diyl) with controlled molecular weight and low polydispersity. In Suzuki–Miyaura catalyst-transfer coupling polymerization, t-Bu3PPd(Ph)Br was an effective catalyst, and well-defined poly(p-phenylene) and poly(3-hexylthiophene) (P3HT) were obtained by concomitant use of CsF/18-crown-6 as a base in tetrahydrofuran (THF) and a small amount of water.

scholarly journals Suzuki–Miyaura Catalyst-Transfer Polycondensation of Triolborate-Type Carbazole Monomers

Polymers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 4168
Author(s):  
Saburo Kobayashi ◽  
Mayoh Ashiya ◽  
Takuya Yamamoto ◽  
Kenji Tajima ◽  
Yasunori Yamamoto ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Diblock Copolymers ◽  
Side Reaction ◽  
Product Formation ◽  
Chain Growth ◽  
Block Copolymerization ◽  
Synthetic Strategy ◽  
Polymerization System ◽  
A Chain ◽  
First Time

Herein, we report the Suzuki–Miyaura catalyst-transfer polycondensation (SCTP) of triolborate-type carbazole monomers, i.e., potassium 3-(6-bromo-9-(2-octyldodecyl)-9H-carbazole-2-yl)triolborate (M1) and potassium 2-(7-bromo-9-(2-octyldodecyl)-9H-carbazole-2-yl) triolborate (M2), as an efficient and versatile approach for precisely synthesizing poly[9-(2-octyldodecyl)-3,6-carbazole] (3,6-PCz) and poly[9-(2-octyldodecyl)-2,7-carbazole] (2,7-PCz), respectively. The SCTP of triolborate-type carbazole monomers was performed in a mixture of THF/H2O using an initiating system consisted of 4-iodobenzyl alcohol, Pd2(dba)3•CHCl3, and t-Bu3P. In the SCTP of M1, cyclic by-product formation was confirmed, as reported for the corresponding pinacolboronate-type monomer. By optimizing the reaction temperature and reaction time, we successfully synthesized linear end-functionalized 3,6-PCz for the first time. The SCTP of M2 proceeded with almost no side reaction, yielding 2,7-PCz with a functional initiator residue at the α-chain end. Kinetic and block copolymerization experiments demonstrated that the SCTP of M2 proceeded in a chain-growth and controlled/living polymerization manner. This is a novel study on the synthesis of 2,7-PCz via SCTP. By taking advantage of the well-controlled nature of this polymerization system, we demonstrated the synthesis of high-molecular-weight 2,7-PCzs (Mn = 5–38 kg mol−1) with a relatively narrow ÐM (1.35–1.48). Furthermore, we successfully synthesized fluorene/carbazole copolymers as well as 2,7-PCz-containing diblock copolymers, demonstrating the versatility of the present polymerization system as a novel synthetic strategy for well-defined polycarbazole-based materials.

Monte Carlo simulation of folding transitions of simple model proteins using a chain growth algorithm

1992 ◽  
Vol 97 (11) ◽  
pp. 8644-8652 ◽  
Author(s):  
Eamonn M. O’Toole ◽  
Athanassios Z. Panagiotopoulos
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Simple Model ◽  
Chain Growth ◽  
A Chain

Preparation of a Novel Magnetic Stir Bar for the Pretreatment of the Plasticizers in Lake Water

2014 ◽  
Vol 989-994 ◽  
pp. 164-167
Author(s):  
Rui Feng
Keyword(s):  
High Performance ◽  
Dibutyl Phthalate ◽  
In Situ Polymerization ◽  
Stir Bar Sorptive Extraction ◽  
Dimethyl Phthalate ◽  
Experimental Conditions ◽  
Sorptive Extraction ◽  
Linear Relationships ◽  
Polymerization Method

An in-situ polymerization method was used for the preparation of a novel stir bar based on neodymium magnet (Nd2Fe14B) powders. The processes were carried out by several steps including the enwrapping of Nd2Fe14B, the modification of the enclosed Nd2Fe14B, and the form of organic polymers on the surface of the modified powders. It was successfully used to enrich the plasticizers in water sample by stir bar sorptive extraction (SBSE). The experimental conditions for SBSE, such as the choice of extraction sorvents, salt concentration, extraction and desorption time were optimized in detail. Coupled to high performance liquid chromatography (HPLC), the recoveries of dibutyl phthalate (DBP), dimethyl phthalate (DMP), diethyl phthalate (DEP) were 89.2%~92.1%, 91.9%~96.6% and 94.3%~96.7%, respectively; the linear relationships between the concentration 5 μg/L and 800 μg/L for DBP were obtained; the limits of detection ranged from 0.09 μg/L to 0.21 μg/L in the optimal conditions.

Importance of choosing the right polymerization method for in situ preparation of semiconducting nanoparticles from the P3HT block copolymer

2016 ◽  
Vol 7 (46) ◽  
pp. 7135-7141 ◽  
Author(s):  
In-Hwan Lee ◽  
Tae-Lim Choi
Keyword(s):  
Block Copolymer ◽  
Molecular Level ◽  
Precise Control ◽  
Semiconducting Nanoparticles ◽  
In Situ Preparation ◽  
The Right ◽  
Polymerization Method

Precise control on synthesis of P3HT-b-PT at the molecular level promotes more controlled in situ nanoparticlization to give more well-defined nanostructures.

Yolk-Shell Fe3O4-Polyaniline Decorated Pd-Ni Nanoparticles with Enhanced Performance for Direct Formic Acid Fuel Cell

NANO ◽  
2017 ◽  
Vol 12 (02) ◽  
pp. 1750016 ◽  
Author(s):  
Akram Hosseinian ◽  
Rahim Hosseinzadeh-Khanmiri ◽  
Ebrahim Ghorbani-Kalhor ◽  
Jafar Abolhasani ◽  
Mirzaagha Babazadeh ◽  
...  
Keyword(s):  
Formic Acid ◽  
Formic Acid Oxidation ◽  
Catalytic Performance ◽  
Ni Catalyst ◽  
Acid Oxidation ◽  
Ni Nanoparticles ◽  
Functional Effect ◽  
Ni Catalysts ◽  
Promotional Effect

The yolk-shell Fe3O4-polyaniline for decoration of Pd-Ni nanoparticles (yolk-shell Fe3O4-PANI/Pd-Ni) were synthesized and used as a new electrocatalyst for oxidation of formic acid. The yolk-shell Fe3O4-PANI/Pd-Ni catalyst provided superior catalyst performance for formic acid oxidation in H2SO4 aqueous solution. These yolk-shell Fe3O4-PANI/Pd-Ni catalysts were found to be more resistant to deactivation in the oxidation of formic acid than yolk-shell Fe3O4-PANI/Pd and Pd/C and to consistently show better long-term performances. The enhanced catalytic performance may arise from the unique structure and surface properties of the yolk-shell Fe3O4-PANI and bi-functional effect, which process extraordinary promotional effect on Pd catalyst.

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