classification of polymers

classification of polymers

1. It is a substance composed of large molecules, or macromolecules (generally organic) formed by the union through covalent bonds of one or more simple units called monomers.

   • Natural polymers
     • There are many polymers in nature and the biomolecules that make up living beings are polymeric macromolecules.
       • For example, proteins, nucleic acids, polysaccharides (such as cellulose and chitin)
   • Semi-synthetic polymers
     • They are obtained by transformation of natural polymers.
       • For example, nitrocellulose, vulcanized rubber, etc.
   • Synthetic polymers
     • Many polymers are made industrially from monomers.
       • For example, nylon, polystyrene, polyvinyl chloride (PVC), polyethylene, etc.
   • Addition polymers
     • Does not involve the release of any low molecular mass compounds.
       • Generated when a catalyst initiates the reaction.
         • Separates the double carbon bond in the monomers that bond with each other thanks to the free electrons and bond successively until the end of the reaction.
   • Condensation polymers
     • Involves the formation of a low molecular mass molecule at each step.
       • Example: Water
   • Polymers formed by chain reaction
     • the initiator reacts with a monomer molecule, giving rise to a free radical, which reacts with another monomer and so on.
       • Polymerization of alkenes.
         • It also includes polymerization where the reactive chains are ions (cationic and anionic polymerization).
   • Polymers formed by stepwise reaction
     • The molecular weight of the polymer grows slowly over time in stages.
       • Monomer disappears quickly, but does not immediately give a high molecular weight polymer.
         • These oligomers begin to react with each other, giving rise to polymeric species.
   • Elastomers
     • Hey are materials with a very low modulus of elasticity and high .
   • Extensibility
     • That is, they deform a lot when subjected to a stress but they regain their initial shape when the stress is eliminated.
   • Adhesives
     • Hey are substances that combine high adhesion and high cohesion, which allows them to join two or more bodies by surface contact.
   • Fibers
     • They have a high modulus of elasticity and low extensibility, which makes it possible to make fabrics whose dimensions remain stable.
   • Plastics
     • They are those polymers that, under a sufficiently intense effort, deform irreversibly, not being able to return to their original shape.

2. Coatings

   • They are substances, normally liquid, that adhere to the surface of other materials to give them some property.
     • Example resistance to abrasion.

3. Organic polymers.

   • It has carbon atoms in the main chain.

4. Vinyl organic polymers

   • The main chain of its molecules is made up exclusively of carbon atoms.

5. Polyolefins

   • formed by the polymerization of olefins.
     • Examples: polyethylene and polypropylene.

6. Styrenic polymers

   • which include styrene among their monomers.
     • Examples: polystyrene and styrene-butadiene rubber.

7. Halogenated vinyl polymers

   • which include halogen atoms (chlorine, fluorine ) in their composition.
     • Examples: PVC and PTFE.

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