Polymers are large macromolecules that contain a large number of repeating units; we call them monomers. The monomers undergo a process called polymerization in order to form a polymer material. An oligomer is also a type of polymer but with a fewer number of repeating units throughout its structure.
What is an Oligomer?
An oligomer is a polymeric material that contains a few numbers of repeating units. Therefore, a few number of monomers undergo polymerization when forming an oligomer. The monomers having either double bonds or two functional groups can undergo this polymerization process to form covalent bonds between them. Eventually, it results in either an oligomer or polymer depending on the number of monomers used up during the process. Instead of calling this process polymerization, we can name it as oligomerization if it forms an oligomer eventually.
Here, if the number of monomers is two, it forms a dimer; three monomers form a trimer, four monomers form a tetramer, etc. Likewise, we can name the oligomers accordingly. Furthermore, there are two major forms of oligomers. Namely, they are the homo-oligomers and hetero-oligomers. Homo-oligomers form when monomers of the same type undergo oligomerization while hetero-oligomers form when monomers of different types undergo oligomerization. Many oils are natural oligomers, and when considering the synthetic ones, plasticizers and polybutene are good examples.
What is a Polymer?
A polymer is a macromolecule containing a large number of repeating units. Therefore, it uses a large number of monomers for the production of this material. The monomers link with each other via covalent bonds after going through the polymerization process. Comparatively, the molecular mass and density of these materials are very high.
Furthermore, there are different classifications that we can use to classify polymers in order to understand their properties easily. Simply, depending on the structure of the polymer material, we can categorize them as linear polymers, branched polymers and network polymers. Or else, we can classify them according to the type of monomer we use for the polymerization. That is; if the same type of monomers used, it gives a homopolymer. But, if different monomers used, it gives a heteropolymer. Above all theses classifications, the most important one is the classification of polymers according to the properties. Accordingly, there are three main classes of polymers. They are; thermoplastics, thermosets and elastomers.
What are the Similarities Between Oligomer and Polymer?
- Oligomer and Polymer form from monomers.
- Hence, both are polymeric structures.
- Also, both have covalent chemical bonds between the monomers.
What is the Difference Between Oligomer and Polymer?
Oligomer is a polymeric material that contains a few numbers of repeating units whereas polymer is a macromolecule containing a large number of repeating units. Therefore, these two materials mainly differ from each other according to the number of monomers that undergo the formation process. Hence, we can say that the key difference between oligomer and polymer is that oligomers form when few monomers undergo polymerization whereas polymers form when a large number of monomers undergo polymerization. However, rather than naming the formation process of oligomers as polymerization, we can name it as oligomerization since it results in an oligomer at the end of the process.
Moreover, we can identify a difference between oligomer and polymer based on their properties. That is; in comparison to oligomers, polymers have higher molecular masses and densities.
Summary – Oligomer vs Polymer
Oligomers are a type of polymers which differs from polymers depending on the number of monomers in the polymer structure. Therefore, the key difference between oligomer and polymer is that the oligomers form when few monomers undergo polymerization whereas the polymers form when a large number of monomers undergo polymerization.