The key difference between copolymer and terpolymer is that copolymers are polymers consisting of more than one type of repeating unit, whereas terpolymers are a type of copolymers that consist of three different types of monomers.
A polymer is a chemical substance consisting of large molecules made from many smaller and simpler molecules, known as monomers. Copolymers and terpolymers are forms of polymers consisting of different types of monomers.
CONTENTS
1. Overview and Key Difference
2. What is Copolymer
3. What is Terpolymer
4. Copolymer vs Terpolymer in Tabular Form
5. Summary – Copolymer vs Terpolymer
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. 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.
There are different forms of copolymers according to the structure of polymer material. Linear copolymers include the following:
- Block copolymers – contain two or more homopolymer subunits linked to each other via covalent bonds.
- Alternating copolymers – contain 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.
Graft polymers are segmented copolymers with a linear backbone of one monomer and randomly distributed branches of another monomer. Here, the side chains are structurally different from the main chain of the polymer. Although they are structurally different from each other, the individual grafted chains may be homopolymers or copolymers.
What is a Terpolymer?
A terpolymer is a type of polymer that is made of three different monomers. Usually, terpolymers are useful in producing biodegradable porous shape-memory scaffolds and in producing wire and cable coverings. Moreover, we can cross-link the terpolymers by an electron beam in order to improve the strength while increasing the softening temperature. A common terpolymer is acrylonitrile-butadiene-styrene terpolymer.
Terpolymers are essentially heteropolymers because there are three different repeating units in the polymer structure. In contrast, a homopolymer contains only one type of repeating unit in the whole polymer molecule.
What is the Difference Between Copolymer and Terpolymer?
Copolymers are a type of polymers. Terpolymers are a type of copolymers. The key difference between copolymer and terpolymer is that copolymers are polymers consisting of more than one type of repeating unit whereas terpolymers are a type of copolymers that consists of three different types of monomers.
The following table summarizes the difference between copolymer and terpolymer.
Summary – Copolymer vs Terpolymer
A copolymer is a polymer material that contains more than one type of repeating unit. A terpolymer is a type of polymer that is made of three different monomers. The key difference between copolymer and terpolymer is that copolymers are polymers consisting of more than one type of repeating units, whereas terpolymers are a type of copolymers that consists of three different types of monomers.
Reference:
1. “Copolymer.” An Overview | ScienceDirect Topics..
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