Addition Polymers – Quick Recap
- Addition polymerization happens when unsaturated monomers (usually with a double bond like alkenes) join together without eliminating any small molecule.
- The monomers just “add” to each other, forming long chains.
- This is common with vinyl monomers (CH₂=CH–R).
Examples of Addition Polymers
1. Polyethylene (PE)
- Monomer: Ethene (CH₂=CH₂).
- Types:
- LDPE (Low-density polyethylene): Flexible, used in plastic bags, films.
- HDPE (High-density polyethylene): Rigid, used in bottles, pipes.
2. Polypropylene (PP)
- Monomer: Propene (CH₂=CH–CH₃).
- Uses: Buckets, ropes, carpets, food containers, medical syringes.
3. Polystyrene (PS)
- Monomer: Styrene (CH₂=CH–C₆H₅).
- Uses: Disposable cups, packaging foam, insulation materials.
4. Polyvinyl Chloride (PVC)
- Monomer: Vinyl chloride (CH₂=CH–Cl).
- Uses: Pipes, flooring, window frames, electrical cable insulation.
5. Polyacrylonitrile (PAN)
- Monomer: Acrylonitrile (CH₂=CH–CN).
- Uses: Synthetic fibers (Orlon), textiles, carpets.
6. Polytetrafluoroethylene (PTFE, Teflon)
- Monomer: Tetrafluoroethene (CF₂=CF₂).
- Uses: Non-stick cookware, lubricants, electrical insulation.
7. Poly(methyl methacrylate) (PMMA)
- Monomer: Methyl methacrylate (CH₂=C(CH₃)COOCH₃).
- Uses: Plexiglass, lenses, transparent windows.
8. Synthetic Rubbers (Addition Type)
- Examples:
- Buna-S rubber: Butadiene + Styrene.
- Buna-N rubber: Butadiene + Acrylonitrile.
- Uses: Tires, hoses, belts, gaskets.
In summary:
Some common addition polymers are:
- Polyethylene (PE)
- Polypropylene (PP)
- Polystyrene (PS)
- Polyvinyl chloride (PVC)
- Polyacrylonitrile (PAN)
- Polytetrafluoroethylene (Teflon, PTFE)
- Poly(methyl methacrylate) (PMMA)
- Synthetic rubbers (Buna-S, Buna-N)