Overview/Checklist

Overview

In this Lesson, we will learn about two additional chain growth polymerization mechanisms: cationic and anionic. These ionic polymerization mechanisms have several similarities to the radical chain growth polymerization in terms of the general mechanism (initiation, propagation, termination). An important distinction is that there will be a charged active center in ionic polymerization (while the radical active center is neutral). This charge is what primarily causes any differences we observe between ionic and radical chain growth. The different charge between cationic (positive charge) and anionic (negative charge) further leads to even more variation among ionic polymerization. Try to compare and contrast the three chain growth mechanisms as you go through the lesson to put in perspective and context how the various pathways are related to monomer chemistry, polymer skeletal structure, and reaction mechanism.

Learning Outcomes

By the end of this lesson, you should be able to:

• Predict if a monomer with polymerize via anionic or cationic pathways
• Compare and contrast ionic polymerization with free radical polymerization
• Draw the arrow pushing mechanism for cationic, anionic, and living anionic polymerization
• Describe the characteristics of living anionic polymerization
• Explain how the solvent and counter ions affect ionic polymerization rates

Lesson Checklist

Please refer to the Canvas Calendar for specific timeframes.

Questions?

If you have questions, please feel free to post them to the General Questions and Discussion forum. While you are there, feel free to post your own responses if you, too, are able to help a classmate.