chain propagation

This process allows for chain propagation of the reaction.

Most metal surface reaction occur by chain propagation.

The mechanism of chain propagation is as follows:

Chain propagation:

Many radical processes involve chain reactions or chain propagation with disproportionation and recombination occurring in the terminal step of the reaction.

Like all chain-growth polymerizations, it takes place in three steps: chain initiation, chain propagation, and chain termination.

Chain propagation (sometimes referred to as propagation) is a process in which a reactive intermediate is continuously regenerated during the course of a chemical reaction.

The unique alternating chain propagation/intramolecular cyclization process eventually leads to the single chain cyclized/knotted polymer architecture.

The reaction with molecular hydrogen (H) involves a chain propagation via regeneration of the atomic hydrogen radical that can perpetuate for many cycles.

There are several main reactions during this polymerization process: initiation, activation, deactivation, chain propagation, intramolecular cyclization and intermolecular crosslinking.

Taking the polymerization of ethylene as an example, the free radical mechanism can be divided into three stages: chain initiation, chain propagation, and chain termination.

Photocurable materials that form through the free-radical mechanism undergo chain-growth polymerization, which includes three basic steps: initiation, chain propagation, and chain termination.

Many radical reactions are chain reactions with a chain initiation step, a chain propagation step and a chain termination step.

Chain Propagation step: A free radical reacts with oxygen to produce a polymer peroxy radical (POO-).

Chain termination and chain transfer reactions are absent and the rate of chain initiation is also much larger than the rate of chain propagation.

This would allow all of the active species to form before chain propagation begins so all of the chains grow at the same rate (the rate of propagation).

In a similar way to normal ATRP, the polymerization is started by initiation to produce a free radical, followed by chain propagation and reversible activation/deactivation equilibrium.

Terminating chain propagation is often most significant during polymerization as the desired chain propagation cannot take place if disproportionation and recombination reactions readily occur.

Another key characteristic is that the rate of initiation (meaning the dormant chemical species generates the active chain propagating species) must be much faster than the rate of chain propagation.

Chain termination is any chemical reaction that ceases the formation of reactive intermediates in a chain propagation step in the course of a polymerization, effectively bringing it to a halt.

Unlike the polymerization of single vinyl monomers, for the polymerization of multivinyl monomers, the chain propagation occurs between the active centres and one of the vinyl groups from the free monomers.

The aryl radical reacts with the nucleophile 4 to a new radical anion 5 which goes on to form the substituted product by transferring its electron to new aryl halide in the chain propagation.

Pathways starting from neutral alkylidene or bisalkyl complexes were found to suffer from high ethylene insertion barriers, whereas a cationic system formed by protonation of the alkylidene show a low barrier for chain propagation.

Ru(bipy) was found to catalyze the fragmentation of tosylphenylselenide to phenylselenolate anion and tosyl radical and that a radical chain propagation mechanism allowed the addition of tosyl radical and phenylseleno- radical across the double bond of electron rich alkyl vinyl ethers.