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Introduction To Organic Chemistry


Polymerization of Alkenes

Polymer is a long-chain molecule formed from repeated building of smaller organic molecules called monomers. Polymerization is the process where more than monomer units combine to form a long-chain. Monomers combine in different ways that include: addition or condensation. The types of polymer that exists are based on two things their origin and formation.

Polymers are originated from natural (from nature) processes. Some examples of natural polymers are: cotton, wool, protein, starch, cellulose, glycogen and deoxyribonucleic acids (DNA). They can also be originated from synthetic (from man made) processes. Some examples of synthetic polymers are: polythene, polyvinylchloride (PVC), polystyrene, nylon and terylene.

Addition polymer results from the addition of unsaturated monomers bonded to form one chain. All addition polymers are synthetic polymers, but not all synthetic polymers are addition polymers. Therefore, alkenes having an unsaturated functional group that is the carbon-carbon double bond will undergo addition polymerisation.

Condensation polymer results from monomers with two or more functional groups reacting to give a polymer plus a small molecule. All natural polmers belong to this group.

Below is an example of propene being polymerized and its equation. (see links in the reference for more information on polymers)

C3H6 + C3H6 C6H12

Propene + Propene Polypropene

Examples of Polymers



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