Question

“Condensation” polymerization involves the formation and loss of a small molecule (such aswater) as each monomer is added to the growing polymer chain. What small molecule would be formed by the reaction of sebacoyl chloride and hexamethylenediamine?

Answer 1

A condensation reaction is a reaction where two (or more) molecules join together to form one larger molecule and a small molecule typically water being produced as a side product.

In this reaction 1,6-hexanediamine or 1,6-diaminohexane (also commonly called hexamethylenediamine) is reacted with sebacoyl chloride (also called decadioyl chloride). Both amine ends of the 1,6-diaminohexane react with both acid chloride ends of the sebacoyl chloride to form new amide linkages. The polymer which forms is made up of alternating 1,6-diaminohexane and sebacoyl groups. This is called an alternating copolymer. This particular Nylon is made of units of 6 carbons between two nitrogen atoms, an amide linkage, an another unit of 10 carbons. This repeats many many times; therefore this is Nylon-6,10. Nylon is used in a wide variety of household product including stockings, windbreakers, shoestrings, car parts, tents, and fishing poles.

The reaction is as follow:

So the small molecule formed is the HCl.

Hope this helps