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"Step growth polymerization" and condensation polymerization are two different concepts, not always identical. In fact polyurethane polymerizes with addition polymerization (because its polymerization produces no small molecules), but its reaction mechanism corresponds to a step-growth polymerization.
In chain-growth (or chain) polymerization, the only chain-extension reaction step is the addition of a monomer to a growing chain with an active center such as a free radical, cation, or anion. Once the growth of a chain is initiated by formation of an active center, chain propagation is usually rapid by addition of a sequence of monomers.
This is true for step-growth polymerization of linear polymers. For chain-growth polymerization or for branched polymers, the Đ can be much higher. In practice the average length of the polymer chain is limited by such things as the purity of the reactants, the absence of any side reactions (i.e. high yield), and the viscosity of the medium.
Acid Chloride Preparative Route for Nylon-6,10, which is often used in the nylon rope trick. The nylon rope trick is a scientific demonstration that illustrates some of the fundamental chemical principles of step-growth polymerization and provides students and other observers with a hands-on demonstration of the preparation of a synthetic polymer.
Condensation polymerization is a form of step-growth polymerization. Linear polymers are produced from bifunctional monomers, i.e. compounds with two reactive end-groups. Common condensation polymers include polyesters, polyamides such as nylon, polyacetals, and proteins. [2] [3]
Polymerization occurs where the two phases meet, at the interface. Interfacial polymerization is a type of step-growth polymerization in which polymerization occurs at the interface between two immiscible phases (generally two liquids), resulting in a polymer that is constrained to the interface.
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.
Condensation polymerization is an important class of step-growth polymerization, which is formed simply by the reaction of two monomers and results in the release of a water molecule. [4] Since these polymers are typically made up of two or more monomers, the resulting end groups are from the monomer functionality.