Overview
In this Lesson, we consider some intricacies of chain polymerization which we have disregarded to this point. For example, you all have learned about the concept of chirality in organic chemistry - is there such a thing for polymers, and how is it controlled? There is, and we call it tacticity - and the tacticity of the polymer has very important ramifications for the polymer properties. What about monomers that are conjugated and can have resonance? We will look at what happens when we polymerize dienes, which have conjugated double bonds, both of which can participate in polymerization. Lastly, we consider a special type of chain growth polymerization where are monomers are actually cyclic, called ring opening polymerization.
Learning Outcomes
By the end of this lesson, you should be able to:
- Identify the tacticity of a polymer.
- Draw the mechanisms for polymerization of dienes leading to 1,2 addition, 3,4 addition, and cis/trans 1,4 addition products.
- Describe the benefits of coordination polymerization and why Ziegler Natta polymerization is used.
- Draw mechanisms and describe the tacticity for cationic and anionic ring opening polymerization.
Lesson Checklist
| Activity | Content | Access / Directions |
|---|---|---|
| To Read | Read through all of the online lesson material for Lesson 7 | Continue navigating the online material. |
| To Read | Chapter 6 - Stereochemistry and Coordination Polymerization
Chapter 7 - Ring-Opening Polymerization
| The chapter readings come from the textbook, Introduction to Polymers |
| To Do | Homework Assignment 7 (Practice) | Registered students can access the homework assignment in the Lesson 7 module. |
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.