The key difference between copolymer and condensation polymer is that the copolymers form via copolymerization whereas the condensation polymers form via condensation reactions.
A polymer is a giant, macromolecule that contains thousands of repeating units linked to each other via covalent chemical bonding. There are several different forms of polymers. We can classify them according to structure, morphology, properties, etc. Copolymers and condensation polymers are such two types.
What is Copolymer?
A copolymer is a polymer material that contains more than one type of repeating unit. Therefore, two or more types of monomers link with each other in forming a copolymer. And, the process of polymerization that forms a copolymer is “copolymerization”. If this copolymerization involves two types of monomers, then the resulting polymer material is a bipolymer. Likewise, if it involves three monomers, then it results in a terpolymer, and if there are four monomers, then it results in a quaterpolymer. Mostly step-growth polymerization results in copolymers.
Also, there are different forms of copolymers according to the structure of polymer material. Linear copolymers include the followings:
- Block copolymers – contains two or more homopolymer subunits linked to each other via covalent bonds.
- Alternating copolymers – contains a regular alternating pattern of two different monomers in a linear structure.
- Periodic copolymers – contain units arranged in a repeating sequence.
- Gradient copolymers – the monomer composition changes gradually along the chain.
Likewise, there are branched structures of copolymers as well. Examples include brush and comb copolymers. Other than that, there are graft copolymers. It has its main chain containing the same type of monomer units and its branched made of a different monomer.
What is Condensation Polymer?
Condensation polymer is a polymer material that forms via a condensation chemical reaction. This reaction involves the joining of molecules with each other while removing byproducts such as water molecules, methanol molecules, etc. Since this reaction forms a polymer, we can name it as polycondensation. Moreover, it is a form of step-growth polymerization.
In this process, a linear polymer forms from monomers containing two functional groups in the same molecule. For instance, compounds with two reactive end groups can undergo this polymerization.
Moreover, the most common condensation polymer materials include polyamides, polyacetals, proteins, etc. Furthermore, these polymers are more biodegradable than other forms of polymers. Especially, in the presence of catalysts or bacterial enzymes, these polymers undergo hydrolysis.
What is the Difference Between Copolymer and Condensation Polymer?
Even though both copolymers and condensation polymers can form via step-growth polymerization processes; some copolymers form via chain-growth polymerization too. Thus, this is an important difference between copolymer and condensation polymer. However, we name the processes of formation of these polymer materials differently, specifying the end product. Therefore, the key difference between copolymer and condensation polymer is that copolymers form via copolymerization whereas condensation polymers form via condensation reactions.
As another important difference between copolymer and condensation polymer, we can say that copolymers contain different types of monomers while condensation polymers can have either same type of monomers or different types of monomers.
Summary – Copolymer vs Condensation Polymer
Copolymers are polymer material containing at least two types of monomers. On the other hand, condensation polymers are polymer materials that form via condensation reactions while removing a small molecule as a byproduct. The key difference between copolymer and condensation polymer is that copolymers form via copolymerization whereas condensation polymers form via condensation reactions.
1. Alison J. Scott, Alexander Penlidis, in Reference Module in Chemistry, Molecular Sciences and Chemical Engineering, 2017
2. Libretexts. “Condensation Polymers.” Chemistry LibreTexts, National Science Foundation, 6 Sept. 2017. Available here