Video Transcript
What is the correct structure of
the condensation polymer formed between the following two monomers?
A polymer is a chemical that can be
formed from similar chemical units called monomers that join together. More specifically, a condensation
polymer is a type of polymer that forms when bits of the monomers break off and the
remainders bond together. The formation of a condensation
polymer is accompanied by the formation of small by-product molecules. To answer the question, we need to
determine the structure of the condensation polymer formed between the two different
monomers given. A polymer produced from two or more
different monomers is called a copolymer.
Let’s take a look at two different
monomers, hexane-1,6-diamine and hexanedioic acid. When these two monomers react, one
monomer loses a hydrogen atom, while the other loses a hydroxy group to form the
by-product water. The remaining portions of the
monomers join together to form the copolymer nylon. Each end of the polymer chain can
go on to react with more monomers, lengthening the polymer. Because the length of the polymer
can vary and is often very large, we represent a polymer by writing the repeating
unit inside of brackets, followed by a subscript 𝑛 that indicates the number of
times the unit repeats.
We can apply our understanding of
condensation copolymers to the monomers given in the question. A and B represent the pieces of the
monomers that break off to form the by-product. The rectangle and oval represent
the pieces of the monomers that bond together to form the condensation polymer. From this, we can see that the
correct structure of the condensation polymer formed between the two monomers given
is the structure shown in answer choice (B).
