4.1.3 Polymers

🧪 What are Polymers?

• Polymers are extremely large molecules made of repeating monomer units.

• The Mayan civilisation was one of the first to use natural polymers (e.g., rubber).

• Synthetic polymers (e.g., Bakelite) were first developed in 1907 and became widely produced in the late 1920s (e.g., PVC).

📌 Key Terms:

• Monomer → Small molecules that join to form polymers.

• Polymer → Large molecules made of many repeating monomer units.

• Addition Polymerisation → The process where monomers with C=C double bonds react to form a long saturated polymer chain.

🔗 Addition Polymerisation

✅ Alkenes undergo addition polymerisation to form long saturated polymer chains.
✅ This process occurs at high temperature and high pressure using catalysts.

📌 Properties of Addition Polymers:

• High molecular mass

• Named after the monomer (e.g., ethene → poly(ethene))

Repeat units written in square brackets

• Letter 'n' shows many repeating units

📌 General Equation:
Monomer (C=C) → Polymer (long saturated chain)

Poly (chloroethene) A.K.A poly (vinyl chloride) or PVC

PVC is known for its flexibility and rigidity, which leads to a variety of uses👇

Other Polymers and their Monomers

Poly(propene)

Poly(phenylethene) A.K.A Poly(styrene)

Poly(tetrafluoroethene) A.K.A Teflon

🔬 Identifying Monomers from Polymers

To find the monomer from a polymer:

1. Identify the repeat unit.

2. Break a single C–C bond into a C=C double bond.

 🌍 Environmental Concerns

🚮 Disposal of Waste Polymers

• Polymers are non-biodegradable, leading to plastic pollution.

• Waste plastics harm marine life.

🔄 Recycling Polymers

• Reduces landfill & conserves fossil fuels.

• Sorting is necessary to avoid contamination.

• PVC recycling is difficult due to toxic chlorine-containing additives.

🔥 Using Polymers as Fuel

• Some waste polymers are burned to generate energy.

• Incineration must be controlled to reduce harmful emissions.