Jove
Visualize
联系我们
JoVE
x logofacebook logolinkedin logoyoutube logo
关于 JoVE
概览领导团队博客JoVE 帮助中心
作者
出版流程编辑委员会范围与政策同行评审常见问题投稿
图书馆员
用户评价订阅访问资源图书馆顾问委员会常见问题
研究
JoVE JournalMethods CollectionsJoVE Encyclopedia of Experiments存档
教育
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab Manual教师资源中心教师网站
使用条款与条件
隐私政策
政策

相关概念视频

Olefin Metathesis Polymerization: Ring-Opening Metathesis Polymerization (ROMP)01:16

Olefin Metathesis Polymerization: Ring-Opening Metathesis Polymerization (ROMP)

3.1K
Ring-opening metathesis polymerization or ROMP involves strained cycloalkenes as starting materials. The mechanism of ROMP proceeds by reacting cycloalkene with Grubbs catalyst to give metallacyclobutane intermediate which undergoes a ring-opening reaction to form new carbene. The new carbene reacts with another molecule of cycloalkene. Repetition of these steps leads to the formation of an unsaturated open-chain polymer product. All these steps are reversible, however, relieving the ring...
3.1K
Molecular Weight of Step-Growth Polymers01:08

Molecular Weight of Step-Growth Polymers

2.7K
Step growth polymerization involves bi or multifunctional monomers. Bifunctional monomers react to form linear step growth polymers, whereas multifunctional monomers react to form non-linear or branched polymers.
As the step-growth polymerization involves step-wise condensation of monomers, the molecular weight also builds up eventually. Consequently, high molecular weight polymers are obtained at the late stages of the polymerization, where 99% of monomers have been consumed.
The extent of the...
2.7K
Olefin Metathesis Polymerization: Overview01:13

Olefin Metathesis Polymerization: Overview

2.5K
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 of a...
2.5K
Polymers: Molecular Weight Distribution01:10

Polymers: Molecular Weight Distribution

4.7K
For any given polymer, the weight average molecular weight (Mw) is higher than, if not equal to, the number average molecular weight (Mn). The only situation in which the weight average molecular weight and the number average molecular weight are equal is when a polymer consists only of chains with equal molecular weight. However, this never happens in a synthetic polymer, since it is difficult to control the polymerization process up to a molecular level with accuracy to a hundred percent.
4.7K
Polymers: Defining Molecular Weight01:01

Polymers: Defining Molecular Weight

3.7K
Unlike small molecules with definite molecular weights, polymers are a mixture of individual polymer chains of varying lengths, each with a unique molecular weight.  So, the molecular weight of a polymer is expressed as an average value based on the average size of the polymer chains. The two most common forms of averages used for polymers are the number average molecular weight and weight average molecular weight.
The number average molecular weight (Mn) is the summation of the number...
3.7K
Olefin Metathesis Polymerization: Acyclic Diene Metathesis (ADMET)00:53

Olefin Metathesis Polymerization: Acyclic Diene Metathesis (ADMET)

2.2K
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...
2.2K

您也可能阅读

相关文章

通过共同作者、期刊和引用图与本文相关的文章。

排序
Same author

Regulating Radical Flux in Frontal Polymerization.

ACS macro letters·2026
Same author

Engineering Free Volume within Frontal Ring-Opening Metathesis Polymerization via Pendant Plasticization.

Advanced materials (Deerfield Beach, Fla.)·2025
Same author

Standardizing Depolymerization: Strategies and Performance Metrics.

Precision chemistry·2025
Same author

Vitrimer Nanocomposites from Polymerization-Induced Self-Assembly.

Advanced materials (Deerfield Beach, Fla.)·2025
Same author

Chemical Activation of Frontal Ring-Opening Metathesis Polymerization.

ACS macro letters·2025
Same author

Tuning Entanglement Molecular Weights with Ultrahigh-Molecular-Weight Polystyrenics.

Journal of the American Chemical Society·2025
Same journal

Proton Transfer Shuttle Mediated Dormant-Active Balance for Accelerated and Controlled Polymerization of N-Carboxyanhydrides.

Angewandte Chemie (International ed. in English)·2026
Same journal

Chloride-Regulated Depolymerization of Aluminosilicate Networks for Fast Ion Transport Compliant Interfaces in Sustainable All-Solid-State Sodium Batteries.

Angewandte Chemie (International ed. in English)·2026
Same journal

Asymmetric Zn─N<sub>2</sub>O-Coordinated Hydrogen-Bonded Organic Frameworks for Electrochemical Hydrogen Peroxide Production and Wastewater Purification.

Angewandte Chemie (International ed. in English)·2026
Same journal

Photocatalytic Cascade Nitrogen Fixation for Selective Purification of Methane-Rich Coal-Bed Gas Over a Bimetallic MOF.

Angewandte Chemie (International ed. in English)·2026
Same journal

Scalable Art-Inspired Tessellated Covalent Organic Framework Membranes Enable Highly Selective Ion Separation.

Angewandte Chemie (International ed. in English)·2026
Same journal

Layered Copper-Anthraquinone Coordination Polymer Cathode Leveraging Dual-Redox Sites and Facilitated Ion Diffusion for High-Performance Lithium-Ion Batteries.

Angewandte Chemie (International ed. in English)·2026
查看所有相关文章

相关实验视频

Updated: Jan 18, 2026

Controlled Photoredox Ring-Opening Polymerization of O-Carboxyanhydrides Mediated by Ni/Zn Complexes
05:48

Controlled Photoredox Ring-Opening Polymerization of O-Carboxyanhydrides Mediated by Ni/Zn Complexes

Published on: November 21, 2017

8.6K

在前环开放转化聚合过程中,分子重量控制.

Kevin A Stewart1, Darya A Ivannikava1, Claire M Massouh1

  • 1Department of Chemistry, University of Utah, Salt Lake City, UT, 84112, USA.

Angewandte Chemie (International ed. in English)
|September 13, 2025
PubMed
概括
此摘要是机器生成的。

这项研究推进了批量前环开放元解聚合 (FROMP) 以精确控制无溶剂的聚合物特性. 新方法产生高分子量和低分散性,使新材料设计成为可能.

关键词:
大量批量货物 批量货物控制的 控制的 控制的额头聚合的聚合.反应制造 反应制造 反应制造环开放转基因聚合的转基因聚合.

更多相关视频

Depolymerizable Olefinic Polymers Based on Fused-Ring Cyclooctene Monomers
08:12

Depolymerizable Olefinic Polymers Based on Fused-Ring Cyclooctene Monomers

Published on: December 16, 2022

3.9K
Synthesis of Monodisperse Cylindrical Nanoparticles via Crystallization-driven Self-assembly of Biodegradable Block Copolymers
11:42

Synthesis of Monodisperse Cylindrical Nanoparticles via Crystallization-driven Self-assembly of Biodegradable Block Copolymers

Published on: June 20, 2019

8.3K

相关实验视频

Last Updated: Jan 18, 2026

Controlled Photoredox Ring-Opening Polymerization of O-Carboxyanhydrides Mediated by Ni/Zn Complexes
05:48

Controlled Photoredox Ring-Opening Polymerization of O-Carboxyanhydrides Mediated by Ni/Zn Complexes

Published on: November 21, 2017

8.6K
Depolymerizable Olefinic Polymers Based on Fused-Ring Cyclooctene Monomers
08:12

Depolymerizable Olefinic Polymers Based on Fused-Ring Cyclooctene Monomers

Published on: December 16, 2022

3.9K
Synthesis of Monodisperse Cylindrical Nanoparticles via Crystallization-driven Self-assembly of Biodegradable Block Copolymers
11:42

Synthesis of Monodisperse Cylindrical Nanoparticles via Crystallization-driven Self-assembly of Biodegradable Block Copolymers

Published on: June 20, 2019

8.3K

科学领域:

  • 聚合物化学 聚合物化学
  • 材料科学 材料科学 材料科学

背景情况:

  • 散装前环开放性转化聚合 (FROMP) 传统上在控制聚合物性质方面面临着挑战.
  • 通常需要溶剂,脱氧和净化步骤,限制可扩展性和效率.

研究的目的:

  • 开发无溶剂FROMP方法,以加强对聚合物分子量和分散性的控制.
  • 探索非线性传播模式,并使用受控FROMP创建梯度材料.

主要方法:

  • 调抑制剂负载和在FROMP中结合抑制性共同体.
  • 使用norbornene型单体进行聚合.
  • 研究热传输,反应动力学和反应前线上的重力效应.

主要成果:

  • 在没有溶剂或净化的情况下,实现了对分子重量 (39-700 kg mol-1) 的精确控制和低分散率 (低至1.07).
  • 在FROMP中展示了第一个封闭模具,非线性传播模式 (旋转模式).
  • 成功构建了具有梯度组成和空间定义变化的材料.

结论:

  • 控制FROMP为先进的材料设计提供了一种强大,可扩展和自我调节的方法.
  • 这项工作将受控聚合技术与自我传播材料制造融合在一起.
  • 这些发现为快速合成具有量身定制性质的复杂聚合物材料铺平了道路.