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Encyclopedia > Addition polymerization

Addition polymerization,also called polyaddition or chain growth polymerization, is a polymerization technique where monomer molecules add on to a growing polymer chain one at a time. Image File history File links Download high-resolution version (844x280, 4 KB)Ring opening polymerization of polycaprolactone. ... This is the article about the process. ... In chemistry, a monomer (from Greek mono one and meros part) is a small molecule that may become chemically bonded to other monomers to form a polymer. ... Polymer is a term used to describe large molecules consisting of repeating structural units, or monomers, connected by covalent chemical bonds. ...

nM (monomer) --> -(-M-)n- (polymer)

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The main characteristics are:

  • polymerization process takes place in three distinct steps:
  1. chain initiation, usually by means of an initiator which starts the chemical process. Typical initiators include any organic compound with a labile group: e.g. azo (-N=N-), disulphide (-S-S-), or peroxide (-O-O-). Two examples are benzoyl peroxide and AIBN.
  2. chain propagation
  3. chain termination, which occurs either by combination or disproportionation. Termination, in radical polymerization, is when the free radicals combine and is the end of the polymerisation process.
  • some side reactions may occur, such as: chain transfer to monomer, chain transfer to solvent, and chain transfer to polymer.

In chemistry initiation is a chemical reaction that triggers one or more secondary reactions. ... Another meaning of initiator is SCSI initiator. ... R-phrases , , S-phrases , , , Autoignition temperature 80°C RTECS number DM8575000 Except where noted otherwise, data are given for materials in their standard state (at 25 Â°C, 100 kPa) Infobox disclaimer and references Tube of Basiron, a water-based 5% benzoyl peroxide preparation for the treatment of acne. ... Azobisisobutyronitrile, also azobisisobutylonitrile, is a toxic white crystalline compound often used as a foamer in plastics and rubber. ... Addition polymerization, also called polyaddition or chain growth polymerization, is a polymerization technique where monomer molecules add on to a growing polymer chain one at a time. ... Addition polymerization, also called polyaddition or chain growth polymerization, is a polymerization technique where monomer molecules add on to a growing polymer chain one at a time. ... Chain transfer is a reaction in radical polymerization by which a radical center on a growing polymer chain is transferred to another molecule. ... Step-growth polymerization is a polymerization process that involves a chemical reaction between multifunctional monomer molecules. ... In chemistry free radicals are uncharged atomic or molecular species with unpaired electrons or an otherwise open shell configuration. ... Radical polymerization is a type of polymerization in which the propagation head of a polymer chain consists of a radical. ... A carbocation is an ion with a positively-charged carbon atom. ... A carbanion is an anion in which carbon has an unshared pair of electrons and bears a negative charge usually with three substituents for a total of eight valence electrons. ... An anionic addition polymerization of vinyl monomers is initiated by a strong base, such as an alkali amide, or an organometallic compound, such as n-butyllithium. ... Organometallic have classically been compounds having bonds between one or more metal atoms and one or more carbon atoms of an organyl group. ... Coordination polymerization is a form of addition polymerization in which monomer adds to a growing macromolecule through an organometallic active center. ... A unsaturated compound in chemistry is a chemical compound that contains carbon - carbon pi bonds such as a alkene or a alkyne. ... Ethylene (or IUPAC name ethene) is the chemical compound with the formula CH2CH2. ... Acetylene (IUPAC name: ethyne) is the simplest alkyne hydrocarbon, consisting of two hydrogen atoms and two carbon atoms connected by a triple bond. ... Vinyl polymers are a group of polymers derived from vinyl monomers such as styrene (polystyrene), vinyl chloride (polyvinylchloride), ethylene (polyethylene), propylene (polypropylene) and butadiene (polybutadiene). ... Cyclopropane is the smallest alicyclic compound. ... In chemistry, ring-opening polymerization is a subset of addition polymerization, in that an end of a growing polymer chain acts as a reactive center that can react with additional monomers to propagate the chain. ... In polymer chemistry, living polymerization is a form of addition polymerization where the ability of a growing polymer chain to terminate has been removed . ...

Some Examples


  Results from FactBites:
 
Addition polymerization - Wikipedia, the free encyclopedia (232 words)
Addition polymerization, also called polyaddition or chain growth polymerization, is a polymerization technique where monomer molecules add on to a growing polymer chain one at a time.
benzoyl peroxide is an initiator for the free radical addition polymerization of styrene to produce polystyrene.
Aluminium chloride is an initiator for the cationic addition polymerization of isobutylene to form isobutyl synthetic rubber.
Living polymerization - Wikipedia, the free encyclopedia (997 words)
The earliest developed forms of living polymerization was anionic addition polymerization, which was discovered independently early in the twentieth century by Ziegler and Natta.
Although not a strictly living form of polymerization catalytic chain transfer polymerization must be mentioned as it figures significantly in the development of later forms of living free radical polymerization polymerization.
This is improved by the addition of a ligand, which significantly improves the solubility of the metal halide and thus the availability of the catalyst but complicates subsequent catalyst removal from the polymer product.
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