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Information about Addition Polymerization

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Ring opening polymerisation to polycaprolactone
Addition polymerisation, also called polyaddition or chain growth polymerization, is a polymerisation technique where unsaturated monomer molecules add on to a growing polymer chain one at a time. It can be represented with the chemical equation:
nM (monomer) --> -(-M-)n- (polymer)

Characteristics

The main characteristics are:
  • polymerisation 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 polymerisation, is when the free radicals combine and is the end of the polymerisation process.

Examples

alkene polymerisation, in which each Styrene monomer unit's double bond reforms as a single bond with another styrene monomer and forms polystyrene.]] In polymer chemistry, polymerization
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In organic chemistry, an unsaturated compound is a chemical compound that contains carbon - carbon pi bonds such as an alkene or an alkyne. In a saturated compound these pi bonds are removed by the addition of hydrogen and no multiple bonds are present.
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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.

Examples of monomers are hydrocarbons such as the alkene and arene homologous series.
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polymer is a substance composed of molecules with large molecular mass composed of repeating structural units, or monomers, connected by covalent chemical bonds. The word is derived from the Greek, πολυ, polu, "many"; and μέρος, meros,
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A chemical equation is a symbolic representation of a chemical reaction. [1] The coefficients next to the symbols and formulae of entities are the absolute values of the stoichiometric numbers. The first-ever chemical equation was diagrammed by Jean Beguin in 1615.
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In chemistry, initiation is a chemical reaction that triggers one or more secondary reactions. Often the initiation reaction generates a reactive intermediate from a stable molecule which is then involved in secondary reactions.
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An initiator can refer to
  • a device used to start the chain reaction in an atomic bomb of the Fat Man type.
  • a chemical compound that initiates a chemical chain reaction.

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Benzoyl peroxide (IPA [ˈbɛnzəʊɪl pəˈrɒksaɪd]) is a chemical in the organic peroxide family.
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Chain propagation is a process in which a reactive intermediate is continuously regenerated during the course of a chemical reaction. In polymerization reaction, the reactive end-groups of a polymer chain react in each propagation step with a new monomer molecule transferring the
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For the DNA sequencing method, see .


Chain termination is any chemical reaction leading to the destruction of a reactive intermediate in a chain propagation step in the course of a polymerization, effectively bringing it to a halt.
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Chain transfer is a reaction in radical polymerization by which a radical center on a growing polymer chain is transferred to another molecule.[1]

P. + XR'
> PX + R'.
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Step-growth polymerization is a polymerization process that involves a chemical reaction between multifunctional monomer molecules. In a step-growth reaction, the growing chains may react with each other to form even longer chains. This applies to chains of all lengths.
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Water is a common chemical substance that is essential to all known forms of life.[1] In typical usage, water refers only to its liquid form or state, but the substance also has a solid state, ice, and a gaseous state, water vapor.
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radicals (often referred to as free radicals) are atomic or molecular species with unpaired electrons on an otherwise open shell configuration. These unpaired electrons are usually highly reactive, so radicals are likely to take part in chemical reactions.
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A carbocation (IPA pronunciation: [kɑ(r)'bəʊkæt'aɪ.ɒn]) is an ion with a positively-charged carbon atom. The charged carbon atom in a carbocation is a "sextet", i.e.
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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 [1]. The carbanion exists in a trigonal pyramidal geometry.
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An anionic addition polymerization of vinyl monomers is an addition polymerization initiated by a strong base and anion, such as an alkali amide, or an organometallic compound, such as n-butyllithium.
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Organometallic chemistry is the study of chemical compounds containing bonds between carbon and a metal.[1] Since many compounds without such bonds are chemically similar, an alternative may be compounds containing metal-element bonds of a largely covalent character.
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Coordination polymerization is a form of addition polymerization in which monomer adds to a growing macromolecule through an organometallic active center. The development of this polymerization technique started in the 1950s with heterogeneous Ziegler-Natta catalysts based on
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In organic chemistry, an unsaturated compound is a chemical compound that contains carbon - carbon pi bonds such as an alkene or an alkyne. In a saturated compound these pi bonds are removed by the addition of hydrogen and no multiple bonds are present.
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Ethylene (or IUPAC name ethene) is the chemical compound with the formula C2H4. It is the simplest alkene. Because it contains a double bond, ethylene is called an unsaturated hydrocarbon or an olefin.
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Acetylene (systematic name: ethyne) is a hydrocarbon belonging to the group of alkynes. It is considered to be the simplest of all alkynes as it consists of two hydrogen atoms and two carbon atoms.
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Vinyl polymers are a group of polymers derived from vinyl monomers. Their backbone is an extended alkane chain, made by polymerizing an alkene group (C=C) into a chain (..-C-C-C-C-..). In popular usage, "vinyl" refers only to PVC.
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alicyclic compound is an organic compound that is both aliphatic and cyclic. They contain one or more all-carbon rings which may be either saturated or unsaturated, but do not have aromatic character.
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ring-opening polymerization is a form of addition polymerization, in which the terminal end of a polymer acts as a reactive center, where further cyclic monomers join to form a larger polymer chain through ionic propogation.
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In polymer chemistry, living polymerization is a form of addition polymerization where the ability of a growing polymer chain to terminate has been removed [1]. This can be accomplished in a variety of ways.
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Benzoyl peroxide (IPA [ˈbɛnzəʊɪl pəˈrɒksaɪd]) is a chemical in the organic peroxide family.
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An initiator can refer to
  • a device used to start the chain reaction in an atomic bomb of the Fat Man type.
  • a chemical compound that initiates a chemical chain reaction.

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Styrene, also known as vinyl benzene as well as many other names (see table), is an organic compound with the chemical formula C6H5CH=CH2.
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Polystyrene IPA: /ˌpɒliˈstaɪriːn/ is a polymer made from the monomer styrene, a liquid hydrocarbon that is commercially manufactured from petroleum by the chemical industry.
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