Intermediate Topic 832 of 1102 Organic Chemistry
Addition Polymers
Formed by chain addition of unsaturated monomers, such as polyethylene and PVC.
In-depth explanation of Addition Polymers
Addition polymers form by chain-growth polymerization, in which unsaturated monomers add to a growing chain by a radical, cationic or anionic mechanism without losing any atoms. Each monomer contributes its full mass to the polymer, so the repeating unit has the same formula as the monomer. Common examples include polyethylene, polypropylene, PVC, polystyrene, PTFE and acrylic polymers. The chain grows rapidly once initiated and typically reaches a very high molar mass in a short time.
Going deeper: Addition Polymers
Key ideas: Formed by chain addition of unsaturated monomers with no by-product, so the repeat unit has the monomer formula. Common ones: polyethylene, polypropylene, PVC (vinyl chloride), polystyrene, PMMA (methyl methacrylate), PAN (acrylonitrile), Teflon (CF2=CF2). Radical initiators such as benzoyl peroxide start the chain. Ziegler-Natta catalyst gives stereoregular polymers with higher density and melting point.
Common mistakes and connections: Students include the double bond in the polymer or forget that chain branching in LDPE arises from backbiting. Another error is naming the polymer after the wrong monomer. Atactic, isotactic and syndiotactic describe the pendant group arrangement. Links to radical chain mechanism and recycling codes.
Visualization of Addition Polymers
Unsaturated monomers add one after another with no byproducts, so the polymer has the same atoms as the monomers. The interactive lesson shows this as a live animation or chart.
Worked example and use case
Tetrafluoroethene polymerizes to form PTFE, known as Teflon, which is extremely chemically resistant.
Frequently asked questions about Addition Polymers
What is Addition Polymers?
Formed by chain addition of unsaturated monomers, such as polyethylene and PVC.
Is Addition Polymers a beginner, intermediate or advanced topic?
Addition Polymers is a intermediate topic in Organic Chemistry. It builds on the vocabulary of beginner topics in this area.
What should I learn before Addition Polymers?
Study these earlier topics in Organic Chemistry first: Lipids, Nucleic Acid Structure, Polymers Overview.
What comes after Addition Polymers?
The next topics in Organic Chemistry are Condensation Polymers and Natural and Synthetic Rubber.
Can I practise Addition Polymers with quizzes?
Yes. The interactive lesson includes a self-check question on Addition Polymers, and the Organic Chemistry quiz draws on every topic in this area.
Where Addition Polymers fits in Organic Chemistry
Addition Polymers is topic 104 of 148 in Organic Chemistry.