Polymers
Polymers are long chains made from repeating monomers.
About this topic
Polymers are very large molecules made from many repeating units called monomers. In addition polymerisation, unsaturated monomers such as ethene join by opening their double bonds, with no by-product, forming polythene, PVC, polypropene and polystyrene. In condensation polymerisation, monomers with two functional groups join and release a small molecule such as water, forming polyesters and nylon.
The properties depend on chain length, branching and the forces between chains. Long straight chains pack neatly, giving strong and dense materials like high-density polythene, while branched chains give softer, flexible plastics. Cross-links, as in vulcanised rubber and thermosetting plastics such as Bakelite, make a material rigid and heat resistant. Thermoplastics soften on heating and can be remoulded, while thermosets cannot. Natural polymers include starch and cellulose from glucose, proteins from amino acids, and DNA from nucleotides.
Example: n CH2=CH2 gives (-CH2-CH2-)n, polythene used for bags and bottles. Nylon is used in clothes and ropes, polyester in fabrics and PET bottles, and Teflon is a non-stick coating. Kevlar is strong enough for bulletproof vests. Plastics are cheap, light and versatile, but most are not biodegradable, creating pollution, so recycling and bioplastics matter.
A misconception is that plastic is one material; there are hundreds of types. Also, recycling symbols show type, not that an item is accepted locally.
Key ideas
- Addition and condensation polymerization
- Polyethylene, nylon
- Plastics last a long time
Quick check
Use cases: where Polymers helps
- Homework: review the key idea behind Polymers before you start a problem set.
- Exam revision: use the quick check to test whether you can recall Polymers without notes.
- Visual learning: play with the interactive lab to see how Polymers changes when you adjust its inputs.
- Teaching a friend: explain Polymers in your own words, then compare your version with the key ideas.
Chemistry explains medicine, food, cleaning products, fuels and building materials.
Frequently asked questions
What is Polymers?
Polymers are long chains made from repeating monomers.
What will I learn in Polymers?
Addition and condensation polymerization. Polyethylene, nylon. Plastics last a long time.
Is Polymers part of Chemistry?
Yes. It is one of 150 Chemistry topics on LearnViz HighSchoolEdu, with 3 key ideas, a live animation and a quick check.
Does the Polymers lab work on a phone or tablet?
Yes. The animation resizes to fit your screen and supports touch, so you can drag, tap and slide with your finger.
How should I study Polymers?
Read the summary and key ideas first, play with the interactive lab to see the idea in motion, then answer the quick check. If you get a question wrong, go back to the key idea it tests.
Do I need an account, and is my progress saved?
No account is needed. Marking a topic as learned is saved in your own browser, so it stays on that device and is not sent to a server.