Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Step-Growth Polymerization: Overview

Step-Growth Polymerization: Overview

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...

Polymers: Molecular Weight Distribution

Polymers: Molecular Weight Distribution

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.

Radical Chain-Growth Polymerization: Overview

Radical Chain-Growth Polymerization: Overview

Chain-growth or addition polymerization is successive addition reactions of monomers with a polymer chain. In radical chain-growth polymerization, the reaction proceeds via a free-radical intermediate. The free radical is formed from radical initiators, which spontaneously generate free radicals by homolytic fission. Organic peroxides (such as dibenzoyl peroxide, as shown in Figure 1) or azo compounds are popular radical initiators. A low concentration ratio of radical initiator to monomer is...

Radical Chain-Growth Polymerization: Mechanism

Radical Chain-Growth Polymerization: Mechanism

The radical chain-growth polymerization mechanism consists of three steps: initiation, propagation, and termination of polymerization. The polymerization initiates when a free radical generated from the radical initiator adds to the unsaturated bond in the monomer. The unpaired electron of the free radical and one π electron in the unsaturated bond creates a σ bond between the free radical and the monomer. As a result, the other π electron in the unsaturated bond converts this species into the...

Ziegler–Natta Chain-Growth Polymerization: Overview

Ziegler–Natta Chain-Growth Polymerization: Overview

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 catalyst, high molecular...

Radical Chain-Growth Polymerization: Chain Branching

Radical Chain-Growth Polymerization: Chain Branching

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...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

[ATM/H2AX and repair of sperm-DNA damage during cryopreservation].

Zhonghua nan ke xue = National journal of andrology·2011

Same author

Predicting accident frequency at their severity levels and its application in site ranking using a two-stage mixed multivariate model.

Accident; analysis and prevention·2011

Same author

Photothermally enhanced photodynamic therapy delivered by nano-graphene oxide.

ACS nano·2011

Same author

[Characteristics of soil respiration in Phyllostachys edulis forest in Wanmulin Natural Reserve and related affecting factors].

Ying yong sheng tai xue bao = The journal of applied ecology·2011

Same author

Quality changes in sea urchin (Strongylocentrotus nudus) during storage in artificial seawater saturated with oxygen, nitrogen and air.

Journal of the science of food and agriculture·2011

Same author

Global effect of an RNA polymerase β-subunit mutation on gene expression in the radiation-resistant bacterium Deinococcus radiodurans.

Science China. Life sciences·2011

Search research articles

Related Experiment Video

Updated: May 27, 2026

Single-Molecule Diffusion and Assembly on Polymer-Crowded Lipid Membranes

Single-Molecule Diffusion and Assembly on Polymer-Crowded Lipid Membranes

Published on: July 19, 2022

Monte Carlo simulation on polymer translocation in crowded environment.

Wei-Ping Cao¹, Li-Zhen Sun, Chao Wang

¹Department of Physics, Zhejiang University, Hangzhou 310027, China.

The Journal of Chemical Physics

|November 11, 2011

Summary

This study explores polymer translocation through pores in crowded environments. Researchers found specific polymer-obstacle interactions can minimize translocation time, even with obstacles present.

More Related Videos

Structure-Based Simulation and Sampling of Transcription Factor Protein Movements along DNA from Atomic-Scale Stepping to Coarse-Grained Diffusion

Structure-Based Simulation and Sampling of Transcription Factor Protein Movements along DNA from Atomic-Scale Stepping to Coarse-Grained Diffusion

Published on: March 1, 2022

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level

Published on: September 26, 2016

Related Experiment Videos

Last Updated: May 27, 2026

Single-Molecule Diffusion and Assembly on Polymer-Crowded Lipid Membranes

Single-Molecule Diffusion and Assembly on Polymer-Crowded Lipid Membranes

Published on: July 19, 2022

Structure-Based Simulation and Sampling of Transcription Factor Protein Movements along DNA from Atomic-Scale Stepping to Coarse-Grained Diffusion

Structure-Based Simulation and Sampling of Transcription Factor Protein Movements along DNA from Atomic-Scale Stepping to Coarse-Grained Diffusion

Published on: March 1, 2022

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level

Published on: September 26, 2016

Area of Science:

Polymer Physics
Computational Chemistry
Statistical Mechanics

Background:

Polymer translocation through nanopores is crucial for biological processes and nanotechnology.
Understanding how external factors like crowding affect translocation is essential for controlling polymer behavior.

Purpose of the Study:

To investigate the impact of static obstacles in a crowded environment on the translocation dynamics of a 3D self-avoiding polymer through a small pore.
To elucidate the role of polymer-obstacle interactions and concentration on translocation time and polymer diffusion.

Main Methods:

Dynamic Monte Carlo simulations were employed to model the polymer translocation process.
The free energy landscape was used to qualitatively explain the influence of obstacles.

Main Results:

Translocation time (τ) is significantly influenced by polymer-obstacle interaction strength and obstacle concentration.
A specific polymer-obstacle interaction was identified, leading to translocation times largely independent of obstacle concentration at low densities.
A scaling relation of τ ~ N(1.25) was observed for strongly driven translocations.
Obstacles alter polymer diffusion, with normal diffusion observed only in dilute or weakly attractive environments, while subdiffusion dominates otherwise.

Conclusions:

The presence and nature of obstacles critically affect polymer translocation dynamics and diffusion.
Tailoring polymer-obstacle interactions can optimize translocation efficiency in crowded systems.
Simulation results provide insights into polymer behavior in complex, confined environments.