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Chain-growth polymerization or chain-growth polymerisation is a polymerization technique where monomer molecules add onto the active site on a growing polymer chain one at a time. [1] There are a limited number of these active sites at any moment during the polymerization which gives this method its key characteristics.
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Living polymerization: A chain polymerization from which chain transfer and chain termination are absent. Note : In many cases, the rate of chain initiation is fast compared with the rate of chain propagation, so that the number of kinetic-chain carriers is essentially constant throughout the polymerization.
In polymer chemistry, ring-opening metathesis polymerization (ROMP) is a type of chain-growth polymerization involving olefin metathesis. [1] The reaction is driven by relieving ring strain in cyclic olefins. [2] A variety of heterogeneous and homogeneous catalysts have been developed for different polymers and mechanisms. [3]
Photocurable materials that form through the free-radical mechanism undergo chain-growth polymerization, which includes three basic steps: initiation, chain propagation, and chain termination. The three steps are depicted in the scheme below, where R• represents the radical that forms upon interaction with radiation during initiation, and M ...
Long chain branches may increase polymer strength, toughness, and the glass transition temperature (T g) due to an increase in the number of entanglements per chain. A random and short chain length between branches, on the other hand, may reduce polymer strength due to disruption of the chains' ability to interact with each other or crystallize.
Polyaddition A polymerization in which the growth of polymer chains proceeds by addition reactions between molecules of all degrees of polymerization. Notes: 1. The growth steps are expressed by: P x +P y → P x+y {x}∈{1,2,…∞};{y}∈{1,2,…∞} where P x and P y denote chains of degrees of polymerization x and y, respectively. 2.
Nitroxide-mediated radical polymerization is a method of radical polymerization that makes use of an nitroxide initiator to generate polymers with well controlled stereochemistry and a very low dispersity. [1] It is a type of reversible-deactivation radical polymerization. A chain growth step in a nitroxide mediated polymerization process.