Jove
Visualize
お問い合わせ
JoVE
x logofacebook logolinkedin logoyoutube logo
JoVEについて
概要リーダーシップブログJoVEヘルプセンター
著者向け
出版プロセス編集委員会範囲と方針査読よくある質問投稿
図書館員向け
推薦の声購読アクセスリソース図書館諮問委員会よくある質問
研究
JoVE JournalMethods CollectionsJoVE Encyclopedia of Experimentsアーカイブ
教育
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab Manual教員リソースセンター教員サイト
利用規約
プライバシーポリシー
ポリシー

関連する概念動画

Free-Radical Chain Reaction and Polymerization of Alkenes02:35

Free-Radical Chain Reaction and Polymerization of Alkenes

8.3K
The conversion of alkenes to macromolecules called polymers is a reaction of high commercial importance. The structure of the polymer is defined by a repeating unit, while the terminal groups are considered insignificant. The average degree of polymerization represents the number of repeating units in the polymer molecule and is denoted by the subscript n.
8.3K
Olefin Metathesis Polymerization: Acyclic Diene Metathesis (ADMET)00:53

Olefin Metathesis Polymerization: Acyclic Diene Metathesis (ADMET)

2.0K
Acyclic diene metathesis polymerization or ADMET polymerization involves cross-metathesis of terminal dienes, such as 1,8-nonadiene, to give linear unsaturated polymer and ethylene. As ADMET is a reversible process, the formed ethylene gas must be removed from the reaction mixture to complete the polymerization process.
Similar to cross-metathesis, ADMET also involves the formation of metallacyclobutane intermediate by [2+2] cycloaddition of one of the double bonds of a terminal diene with...
2.0K
Cycloaddition Reactions: MO Requirements for Photochemical Activation01:12

Cycloaddition Reactions: MO Requirements for Photochemical Activation

2.2K
Some cycloaddition reactions are activated by heat, while others are initiated by light. For example, a [2 + 2] cycloaddition between two ethylene molecules occurs only in the presence of light. It is photochemically allowed but thermally forbidden.
2.2K
Olefin Metathesis Polymerization: Overview01:13

Olefin Metathesis Polymerization: Overview

2.3K
Recently, the development of olefin metathesis polymerization advanced the field of polymer synthesis. Simply put, the reorganization of substituents on their double bonds between two olefins in the presence of a catalyst is known as the olefin metathesis reaction. The use of metathesis reaction for polymer synthesis is called olefin metathesis polymerization.
Ruthenium-based Grubbs catalyst is the most commonly used catalyst for olefin metathesis polymerization. Grubbs catalyst consists...
2.3K
Radical Chain-Growth Polymerization: Chain Branching01:17

Radical Chain-Growth Polymerization: Chain Branching

2.0K
The skeletal structure of polymers synthesized via radical polymerization is always branched. For example, the polymerization of ethylene by radical polymerization results in a low-density grade of polyethylene with a heavily branched skeletal structure. Here, the radical site abstracts hydrogen from the growing chain, and the radical site shifts from the end (a primary carbon center) to anywhere within the growing chain (a secondary carbon center). Consequently, the part of the chain from the...
2.0K
Anionic Chain-Growth Polymerization: Mechanism01:04

Anionic Chain-Growth Polymerization: Mechanism

2.1K
The mechanism for anionic chain-growth polymerization involves initiation, propagation, and termination steps. In the initiation step, a nucleophilic anion, such as butyl lithium, initiates the polymerization process by attacking the π bond of the vinylic monomer. As a result, a carbanion, stabilized by the electron‐withdrawing group, is generated. The resulting carbanion acts as a Michael donor in the propagation step and attacks the second vinylic monomer, which acts as a Michael...
2.1K

こちらも読む

関連記事

共著者、ジャーナル、引用グラフによってこの研究に関連する記事。

並び替え
Same author

Atomic Visualization of Surface Photovoltage Effect on Si(111)-(7 × 7) with Gated Integrating Laser-Combined Scanning Tunneling Microscopy.

The journal of physical chemistry letters·2026
Same author

Computing Anharmonic Free Energies in Solids with Machine-Learning Interatomic Potentials.

The journal of physical chemistry letters·2026
Same author

Unmasking true confinement effects: ultrahigh linear selectivity and chain-length oscillatory behavior in zeolite-encapsulated rhodium hydroformylation.

National science review·2026
Same author

Quantum Phase Transition of a Molecular Radical Pair.

Journal of the American Chemical Society·2026
Same author

Monolayered Metal-Organic Frameworks as Fully Exposed Supports for Ligand-Free Photodeposition of Ultrasmall Metal Nanoparticles.

Journal of the American Chemical Society·2026
Same author

Fully Exposed Platinum-Palladium Heteronuclear Cluster for Enhanced Multi-Step Hydrogenation of Dinitroaromatics.

Angewandte Chemie (International ed. in English)·2026

関連する実験動画

Updated: Sep 30, 2025

Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization
07:28

Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization

Published on: November 27, 2015

13.3K

エチレン挿入による表面エチレンポリメリゼーションの可視化

Weijun Guo1,2, Junqing Yin3, Zhen Xu2

  • 1SynCat@Beijing, Synfuels China Technology Co., Ltd., Beijing 101407, China.

Science (New York, N.Y.)
|March 10, 2022
PubMed
まとめ

この研究では,スキャニングトンネル顕微鏡を用いてエチレンポリメリゼーションを可視化しています. 鉄炭化物表面の自己発射メカニズムを明らかにし,分子レベルでエチレン挿入経路を確認しました.

さらに関連する動画

A Simple and Efficient Protocol for the Catalytic Insertion Polymerization of Functional Norbornenes
09:08

A Simple and Efficient Protocol for the Catalytic Insertion Polymerization of Functional Norbornenes

Published on: February 27, 2017

10.6K
Utilizing the Ethylene-releasing Compound, 2-Chloroethylphosphonic Acid, as a Tool to Study Ethylene Response in Bacteria
08:51

Utilizing the Ethylene-releasing Compound, 2-Chloroethylphosphonic Acid, as a Tool to Study Ethylene Response in Bacteria

Published on: November 10, 2016

8.1K

関連する実験動画

Last Updated: Sep 30, 2025

Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization
07:28

Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization

Published on: November 27, 2015

13.3K
A Simple and Efficient Protocol for the Catalytic Insertion Polymerization of Functional Norbornenes
09:08

A Simple and Efficient Protocol for the Catalytic Insertion Polymerization of Functional Norbornenes

Published on: February 27, 2017

10.6K
Utilizing the Ethylene-releasing Compound, 2-Chloroethylphosphonic Acid, as a Tool to Study Ethylene Response in Bacteria
08:51

Utilizing the Ethylene-releasing Compound, 2-Chloroethylphosphonic Acid, as a Tool to Study Ethylene Response in Bacteria

Published on: November 10, 2016

8.1K

科学分野:

  • カタリシス
  • ポリマー化学
  • 表面科学

背景:

  • 触媒によるエチレンポリメリゼーションは,ポリエチレンを生産する化学工業の礎石です.
  • 広く受け入れられているCosse-Arlmanメカニズムは,金属-炭素結合にエチレンを挿入することによって鎖の成長を説明する.
  • このメカニズムの実験的,分子レベルでの確認は欠けています.

研究 の 目的:

  • エチレンポリメリゼーション機構の直接的,顕微鏡的,空間時間的実験的証拠を提供すること.
  • 分子レベルでエチレンポリメリゼーションのプロセスを視覚化します.
  • 特定の触媒表面でのエチレンポリメリゼーションの開始と増殖のステップを明らかにする.

主な方法:

  • スキャントンネル顕微鏡 (STM) を使用したエチレンポリメリゼーションのインサイト可視化.
  • 炭素化鉄の単結晶表面を触媒として使った
  • ポリメリゼーション中間物質と鎖成長の動態の観察

主要な成果:

  • エチレンポリメリゼーションは,炭化物ドメインの境界にある特定の三角形の鉄部位で発生することが観察されました.
  • 表面に固定されたエチリデンの中間物質を含む新しい自己開始経路が特定されました.
  • この中間体へのエチレン挿入が視覚化され,鎖の成長が確認されました.

結論:

  • 直接的な実験的証拠は分子レベルでエチレンポリメリゼーション経路を確認しています.
  • この発見はCossee-Arlmanメカニズムの理解を検証し,精進しています.
  • この研究は,触媒的ポリメリゼーションにおける特定の表面部位と中間物質の役割を強調しています.