Polymerization

Source: Vy M. Dong and Jan Riedel, Department of Chemistry, University of California, Irvine, CA

Polymers are made from macromolecules, which are composed of repeating units (the so called monomeric units). In our modern world, polymers play an important role. One of the first important polymers was nylon, which is a polyamide. It found widespread application in tooth brushes and stockings.

1. Preparation

1. To a 250 mL beaker, add 3 mL (14 mmol) of sebacoyl chloride in 100 mL n-hexane.
2. To a 150 mL beaker, add 4.4 g (38 mmol) of 1,6-diaminohexane in 50 mL distilled water.
3. Add approximately 5 drops of a phenolphthalein solution to the 1,6-diaminohexane solution.

2. Surface Polymerization

1. Overlay carefully the aqueous solution with the sebacoyl chloride solution.
2. Note that a thin layer will form at the interface of

A hollow, long strand of polyamide is obtained.

This experiment showcases in a vivid way the synthesis of a polymer in a simple fashion. The condensation polymerization of 1,6-diaminohexane and sebacoyl chloride gives a polyamide-6,10, which polymerizes at the interface of two liquid layers. This surface polymerization will form a hollow strand of polyamide, after pulling the polymer from the interface and wrapping it around a glass rod to wind it.

Polymers and polyamide find a variety of different uses in our daily life. Initially used for