Catalysis articles within Polymer Journal

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  • Original Article |

    Coordination polymerization of a series of 2-substituted-[3]dendralenes was investigated. No polymerization was observed for 2-trimethylsilyl[3]dendralene, whereas 2-phenyl[3]dendralene polymerized by CpTiCl3 as a catalyst and modified methylaluminoxane as an auxiliary catalyst to generate polymers that became insoluble in the process of isolation. Additionally, the coordination polymerization of 2-hexyl[3]dendralene was conducted using a CpTiCl3/modified methylaluminoxane catalyst to produce polymer with mainly a trans-4,6 structure, which differs from that of the polymer obtained via anionic polymerization. The copolymerization of isoprene with 2-hexyl[3]dendralene was also examined.

    • Tomoyuki Toda
    • , Yuki Takamura
    •  & Katsuhiko Takenaka

  • Original Article |

    Polymer gels containing an iridium complex in their compartmentalized nanodomain structures were designed. Novel Ir-containing vinyl monomers were first synthesized and then incorporated into homogeneously dispersed thermoresponsive nanodomains via living radical polymerization. The product gels exhibited immediate color change by sensing ammonia in a thermoresponsive manner, and catalyzed the N-alkylation reaction. These findings strongly supported the importance of the incorporation of organometallic complexes into the nanodomain of hydrogels for the further development of a novel soft material exhibiting selective molecular recognition abilities and catalytic reactions.

    • Shohichi Furukawa
    • , Takahiro Okuno
    •  & Shohei Ida

  • Original Article |

    Conducting polymer support with atomically dispersed metal centers for oxygen reduction and evolution reaction catalysis is a promising strategy to enhance the cyclability of Li–O2 battery. We present a novel, reliable and highly efficient noble metal free polymer catalyst for Li air battery application. Novel cathode catalyst found to be very efficient for nearly 160 cycles with limiting the capacity to 500 mAh/g with relatively lower overpotential.

    • Rajashekar Badam
    • , Mayu Shibuya
    •  & Noriyoshi Matsumi

  • Original Article |

    Selective adsorption of trialkylaluminums (R3Al) in modified methylaluminoxane (MMAO) onto crosslinked terpolymer bearing bulky phenoxy groups was performed. The phenoxy groups on the terpolymer can more selectivity react with R3Al than the hydroxy groups on SiO2, and some R3Al was physically adsorbed into the terpolymer. As a result, more efficient removal of R3Al from MMAO solution was achieved. The propylene polymerization using terpolymer-treated MMAO as a cocatalyst was free from chain transfer reaction, which is generally derived from the residual R3Al.

    • Ryo Tanaka
    • , Mari Nishizono
    •  & Takeshi Shiono

  • Original Article |

    A highly random terpolymer of CO2, styrene oxide (SO), and propylene oxide (PO) was realized by using a tetraphenylporphyrinatocobalt(III) chloride ((TPP)CoCl)/4-dimethylamino pyridine (DMAP) catalyst system. In contrast, gradient terpolymers were formed in the cases of CO2, cyclohexylethylene oxide (CyEO), tert-butylethylene oxide (tBuEO) or 1-adamantylethylene oxide (AdEO), and PO. The glass transition temperatures (Tgs) of these terpolymers are tunable between that of the copolymer of CO2 with PO (34 °C) and that of the copolymers of CO2 with the corresponding epoxide with bulky side groups.

    • Masayoshi Honda
    • , Takuya Ebihara
    •  & Hiroshi Sugimoto

  • Review |

    The use of iron catalysts in CO2/epoxide chemistry has been less explored compared with zinc, cobalt, and chromium catalysts. This review highlights recent examples including iron complexes that deoxygenate epoxides in situ and geometry-dependent selectivity towards either polycarbonate or cyclic carbonate production. Reaction conditions (temperature, CO2 pressure, and amount of nucleophilic cocatalyst) and catalyst structure are all critical in accessing efficient catalysis for polycarbonate formation.

    • Kori A. Andrea
    •  & Francesca M. Kerton

  • Review |

    A variety of catalysts including zinc, cobalt and chromium complexes were reviewed for the copolymerization of epoxides and CO2 with cyclic anhydrides and/or cyclic esters to synthesize CO2-based poly(ester-co-carbonate)s. The structure and structure-performance relationship of the as-prepared copolymers were discussed in detailed.

    • Jiaxin Liang
    • , Shuxian Ye
    •  & Yuezhong Meng

  • Focus Review |

    To establish effective chemical transformations, catalytic systems with advantages such as high activity, recyclability, durability, and operability have attracted considerable attention. One of the strategies for the development of high-performance catalytic systems is the use of polymer hydrogels. In this focus review, an overview of our research using poly(N-isopropyl acrylamide)-based hydrogel particles and macroporous monoliths as molecular catalysts and loading matrices for palladium catalysts is summarized.

    • Hirokazu Seto
    • , Hikaru Matsumoto
    •  & Yoshiko Miura

  • Original Article |

    A new nickel diphosphine catalyst was synthesized and evaluated for Suzuki–Miyaura cross-coupling polymerization. The diphosphine is comprised of two electronically and sterically distinct phosphine donors, a PPh2 group and a PEt2 group. The catalyst was employed to bring about controlled polymerization of a 3-hexylthiophene monomer to afford poly(3-hexylthiophene). The catalyst was particularly effective for bringing about this polymerization in the presence of excess free ligand. The catalyst resting state was also probed using NMR spectroscopy and an externally initiated catalyst.

    • Matthew A. Baker
    • , Josué Ayuso-Carrillo
    •  & Kevin J. T. Noonan

  • Original Article |

    Single-walled carbon nanotubes (SWCNTs) wrapped by poly[2,2’-(2,6-pyridine)-5,5’-bibenzimidazole] (PyPBI) was used for a cathode material of lithium (Li)-oxygen (O2) rechargeable battery. Compared to the Li–O2 cell using nonwrapped SWCNTs, the cell using PyPBI-wrapped SWCNTs showed improved rechargeability during charge–discharge cycles. It was revealed that PyPBI layer facilitated the homogeneous deposition of the discharge products, resulting the smooth reaction during the cycles. The coordination of Li ion onto PyPBI surface might be the key mechanism to realize the homogeneous deposition.

    • Tsuyohiko Fujigaya
    • , Ryota Kanamori
    •  & Naotoshi Nakashima

  • Focus Review |

    This review describes the N-heterocyclic carbene-catalyzed transformations of Michael acceptors that were developed by our research group, including (1) tail-to-tail dimerization of a wide variety of substrates, such as vinyl pyridines, acrylates, methacrylates and methacrylonitrile, (2) cyclotetramerization of acrylates to form trisubstituted cyclopentenones, (3) tandem oxa-Michael addition and head-to-tail dimerization of methacrolein and (4) oxa-Michael addition polymerization of hydroxyl-functionalized acrylates.

    • Shin-ichi Matsuoka

  • Invited Review |

    Half-metallocene complexes of the type CpM(L^L)X2 (L^L=chelating ligands) offer the advantage of catalyst modification: by changing one cyclopentadienyl ligand of metallocene complexes to other ligands such as three-, four-, five-, six- and seven-membered chelates, bidentate and tridentate coordination, and monoanionic, dianionic and trianionic system, steric and/or electronic modification of the coordination environment is much flexible. The structural uniqueness of the metal complexes and the effects of the chelate ring sizes on their productivity and activation processes of the metal complexes with cocatalysts are highlighted.

    • Hayato Tsurugi
    • , Keishi Yamamoto
    •  & Kazushi Mashima

  • Original Article |

    A bifunctional cobalt Salen complex containing a Lewis acid metal center and two covalent bonded Lewis base units on the ligand was designed and used for the coupling of carbon dioxide (CO2) and epoxides at mild conditions. The Tg of the propylene oxide/cyclohexene oxide/CO2 terpolymer can be easily adjusted between 40 and 118.9 °C.

    • Hongchun Li
    •  & Yongsheng Niu

  • Invited Review |

    The metal-catalyzed living radical polymerization has now been developed diversely in terms of the catalytic systems, controllable monomers, well-defined polymer structures and combinations with stereospecific radical polymerization. This review describes a short overview of recent developments in metal-catalyzed living radical polymerization mainly focusing on our recent research studies related to the subject.

    • Masami Kamigaito

  • Note |

    Polyethylene glycol-containing hematin (PEGylated hematin) was prepared using the Mitsunobu reaction as a water-soluble biomimetic catalyst for polymerization of arbutin in a phosphate buffer solution of pH 7.0. The structure of polyarbutin obtained was characterized by 1H nuclear magnetic resonance and infrared spectroscopy. PEGylated hematin showed high catalytic activity for arbutin polymerization, indicating that it is a better catalyst compared with horseradish peroxidase.

    • Michinari Kohri
    • , Haruka Fukushima
    •  & Takayuki Nakahira

  • Original Article |

    Binary catalysts composed of cationic rhodium complexes, [(tfb)Rh(L)2]X (tfb: tetrafluorobenzobarrelene, L: phosphine ligand, X: counter anion), and iPrNH2 induced living polymerization of phenylacetylene and its ring-substituted derivatives. The living nature was confirmed by kinetic plots of the polymerization. Nuclear magnetic resonance studies revealed that iPrNH2 serves to dissociate the coordinating PPh3 ligand of [(tfb)Rh(L)2]X to form an initiating species. Block copolymers were synthesized by the sequential polymerization of different phenylacetylenes using the present catalyst.

    • Masashi Shiotsuki
    • , Naoya Onishi
    •  & Toshio Masuda

  • Original Article |

    The synthesis and photo-polymerization of hyperbranched polyesters containing pendant methacryloyl groups (HBPE-MA) were examined. Polycondensations of 1,4-bis(chloromethyl)benzene (BCMB) with 1,3,5-benzenetricarboxylic acid (BTCA) proceeded very smoothly to give the soluble hyperbranched polyesters (HBPE) in satisfactory high yields using 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU). Furthermore, HBPE-MA was synthesized by the reaction of HBPE with methacrylic acid (MAA) by the DBU method. The photo-induced radical polymerization of HBPE-MA was performed in the presence of 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-2-one (Irgacure 907) as a photoinitiator in the film state upon UV irradiation to afford the insoluble cured film.

    • Ken Maruyama
    • , Toshiaki Hirabayashi
    •  & Tadatomi Nishikubo

  • Original Article |

    Phosphorus-containing fire retardants and inert polymers inhibit the hydrolysis of polycarbonate (PC), resulting in an increased reaction time. However, even in the presence of these materials, high yields of bisphenol-A and other phenols can be obtained from waste PC dependent on temperature. At 500 °C, polystyrene is also pyrolyzed.

    • Guido Grause
    • , Norihiro Tsukada
    •  & Toshiaki Yoshioka

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