Alizarin Can Dye Nylon Blue: Curiosity-Driven Learning of a Basic Paradigm of Intermolecular Force

This work presents a demonstration that nylon can be dyed blue by using alizarin, a well-known red dye. This demonstration was developed to empower the basic understanding of students about intermolecular forces from the point of view of underlying fundamentals such as electronegativity, polar covalent bonds, and electrostatic attraction within the general educational context of first-year undergraduates. The teaching material first shows the blue dyeing of nylon as a strange phenomenon to stimulate curiosity among the students. Then, the reason underlying the phenomenon is considered and explained using a 2D molecular model made using magnets. Students can visualize how the model alizarin attracts the model nylon.