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

Types of Step-Growth Polymers: Polyesters01:20

Types of Step-Growth Polymers: Polyesters

2.5K
The introduction of polyesters has brought major development to the textile industry. The wrinkle-free behavior of polyester blends has eliminated the need for starching and ironing clothes.
Polyesters are commonly prepared from terephthalic acid and ethylene glycol; the crude product is known as poly(ethylene terephthalate) or PET. However, polyesters are synthesized industrially by transesterification of dimethyl terephthalate with ethylene glycol at 150 °C. The two reactants and the polymer...
2.5K
Step-Growth Polymerization: Overview01:03

Step-Growth Polymerization: Overview

4.2K
Step-growth or condensation polymerization is a stepwise reaction of bi or multifunctional monomers to form long-chain polymers. As all the monomers are reactive, most of the monomers are consumed at the early stages of the reaction to form small chains of reactive oligomers, which then combine to form long polymer chains in the late stages. Hence, the reaction has to proceed for a long time to achieve high molecular weight polymers.
Many natural and synthetic polymers are produced by...
4.2K
Polymer Classification: Architecture01:14

Polymer Classification: Architecture

3.6K
Polymers are classified as linear or branched on the basis of their chain architecture. The polymer chains in linear polymers have a long chain-like structure with minimal to no branching at all. Even if a polymer features large substituent groups on the monomer, which appear as branches to the skeleton, it is not considered a branched polymer. A branched polymer contains secondary polymer chains that arise from the main polymer chain. The branching occurs when the polymer growth shifts from...
3.6K
Anionic Chain-Growth Polymerization: Mechanism01:04

Anionic Chain-Growth Polymerization: Mechanism

2.4K
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...
2.4K
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
Ziegler–Natta Chain-Growth Polymerization: Overview01:17

Ziegler–Natta Chain-Growth Polymerization: Overview

3.8K
Ziegler–Natta polymerization is another form of addition or chain‐growth polymerization used for synthesizing linear polymers over branched polymers. The catalyst used for polymerization is the Ziegler–Natta catalyst, named after Karl Ziegler and Giulio Natta, who developed it in 1953. This catalyst is an organometallic complex of titanium tetrachloride and triethyl aluminum, with the active form of the catalyst being an alkyl titanium compound. Using the Ziegler–Natta...
3.8K

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

Mechanophore cross-linking enhances ballistic energy dissipation of polymers.

Nature·2026
Same author

Extending BigSMILES to Include Topological Bonds.

ACS macro letters·2026
Same author

Force-Accelerated Ring Opening of Episulfide by Pulsed Ultrasonication.

Macromolecules·2026
Same author

Optimizing the Stability of Viral Nanoparticles: Engineering Strategies, Applications, and the Emerging Concept of the Virophore.

Journal of the American Chemical Society·2026
Same author

Switching and Quantifying the Single-Molecule Mechanochemical Reactivity of Four-Membered Carbocycle Mechanophores within a Single, Photoswitchable Polymer Strand.

Journal of the American Chemical Society·2025
Same author

Tetrafunctional cyclobutanes tune toughness via network strand continuity.

Nature chemistry·2025
Same journal

Radical Cascades on Seawater Microdroplets Drive Atmospheric Mercury Oxidation.

Journal of the American Chemical Society·2026
Same journal

Superior Selective and Fast NH<sub>3</sub> Adsorption of Soft Porous MOF/Ionic Liquid Composites with Ordering Phase Transitions.

Journal of the American Chemical Society·2026
Same journal

Systematic Catalyst Variation for Improved Stereoselective Epoxide Polymerization: Subtle Modifications Resulting in Superior Efficiency.

Journal of the American Chemical Society·2026
Same journal

Deciphering the Halide Chemistry of Cl<sup>-</sup> and Br<sup>-</sup> in Enhancing Kinetics of Mg Plating/Stripping.

Journal of the American Chemical Society·2026
Same journal

Electrosynthesis of C<sub>6</sub> Chemicals by Propylene Oxidative Coupling on Au Surface.

Journal of the American Chemical Society·2026
Same journal

Statistical AI Enables Precise Screening of Multielement Catalysts.

Journal of the American Chemical Society·2026
查看所有相关文章

相关实验视频

Updated: Dec 30, 2025

Fabricating Degradable Thermoresponsive Hydrogels on Multiple Length Scales via Reactive Extrusion, Microfluidics, Self-assembly, and Electrospinning
12:07

Fabricating Degradable Thermoresponsive Hydrogels on Multiple Length Scales via Reactive Extrusion, Microfluidics, Self-assembly, and Electrospinning

Published on: April 16, 2018

13.9K

机械封闭的可降解聚合物

Yangju Lin1, Tatiana B Kouznetsova1, Stephen L Craig1

  • 1Department of Chemistry , Duke University , Durham , North Carolina 27708 , United States.

Journal of the American Chemical Society
|January 16, 2020
PubMed
概括
此摘要是机器生成的。

这项研究引入了一种新的聚合物设计,通过需要机械力和酸触发器来防止过早的降解. 这种双激活策略提高了聚合物在储存和使用期间的稳定性.

更多相关视频

Electrospun Fibrous Scaffolds of Polyglycerol-dodecanedioate for Engineering Neural Tissues From Mouse Embryonic Stem Cells
08:03

Electrospun Fibrous Scaffolds of Polyglycerol-dodecanedioate for Engineering Neural Tissues From Mouse Embryonic Stem Cells

Published on: June 18, 2014

11.2K
Microwave-assisted Functionalization of Polyethylene glycol and On-resin Peptides for Use in Chain Polymerizations and Hydrogel Formation
15:33

Microwave-assisted Functionalization of Polyethylene glycol and On-resin Peptides for Use in Chain Polymerizations and Hydrogel Formation

Published on: October 29, 2013

29.6K

相关实验视频

Last Updated: Dec 30, 2025

Fabricating Degradable Thermoresponsive Hydrogels on Multiple Length Scales via Reactive Extrusion, Microfluidics, Self-assembly, and Electrospinning
12:07

Fabricating Degradable Thermoresponsive Hydrogels on Multiple Length Scales via Reactive Extrusion, Microfluidics, Self-assembly, and Electrospinning

Published on: April 16, 2018

13.9K
Electrospun Fibrous Scaffolds of Polyglycerol-dodecanedioate for Engineering Neural Tissues From Mouse Embryonic Stem Cells
08:03

Electrospun Fibrous Scaffolds of Polyglycerol-dodecanedioate for Engineering Neural Tissues From Mouse Embryonic Stem Cells

Published on: June 18, 2014

11.2K
Microwave-assisted Functionalization of Polyethylene glycol and On-resin Peptides for Use in Chain Polymerizations and Hydrogel Formation
15:33

Microwave-assisted Functionalization of Polyethylene glycol and On-resin Peptides for Use in Chain Polymerizations and Hydrogel Formation

Published on: October 29, 2013

29.6K

科学领域:

  • 聚合物化学
  • 材料科学
  • 机械化学

背景情况:

  • 传统的聚合物存在于环境中, 推动对可降解替代品的需求.
  • 可降解的聚合物经常遭受意外的骨干裂变,从而降低了它们的效用.
  • 现有的可降解聚合物缺乏对降解触发器的强大控制.

研究的目的:

  • 开发一种高稳定的聚合物系统,防止过早的降解.
  • 使用机械力和酸实现双触发降解机制.
  • 创建一个"AND门"系统,其中两种刺激都是聚合物骨干分裂所需的.

主要方法:

  • 作为机械门的循环butan (CB) 机械孔的结合.
  • 在聚合物骨干中集成CB-gated的酸敏感.
  • 使用超声波进行机械力和酸处理进行降解研究.
  • 使用单分子力光谱 (SMFS) 来量化机械激活力.

主要成果:

  • 聚合物仅在酸触发下或仅在机械力下保持完整 (限制MW为28kDa).
  • 连续处理 (超声波接着酸) 导致显著的降解 (降低11倍至2.5kDa).
  • 在100毫秒的时间尺度上,CB机械的激活需要大约2nN的力.

结论:

  • "AND门"战略有效地防止了无意的聚合物降解.
  • 这种可控降解系统提供了更好的稳定性和量身定制的终生性能.
  • 这些发现为更耐用,更环保的可降解聚合物铺平了道路.