Plastics and pollution

1. Disadvantages of Polymer Usage

• Non-biodegradable – plastics persist in the environment for years.
• Landfill waste – takes up space and fills up quickly.
• Toxic emissions – burning plastics releases harmful gases.
• Litter problems – pollutes water bodies and landscapes.

2. Recycling of Plastics

• Biodegradable plastics exist but are expensive.

• Recycling reduces waste but requires public awareness and proper facilities. 🔹 Problems with Recycling:

• Not all plastics can be recycled.

• Limited access in rural areas.

• High costs for collection and processing.

• Lack of awareness in communities.

3. Types of Recyclable Plastics

Plastic Type	Symbol	Recycled Into
High-Density Polyethene (HDPE)	♻ $02$ $PE-HD$	Rubbish bins, rulers, plastic furniture.
Low-Density Polyethene (LDPE)	♻ $04$ $PE-LD$	Plastic bags, flooring, bin liners.

4. Key Definitions

✅ Macromolecule: A large molecule made of many atoms.

✅ Monomer: A small molecule that joins with others to form a polymer.

✅ Polymerisation: A reaction where monomers combine to form a polymer.

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5. Polymerisation Types

Type	Process	Example
Addition Polymerisation	Monomers add together without losing atoms.	Ethene → Polyethene
Condensation Polymerisation	Monomers join, losing a small molecule (e.g., $H₂O$).	Nylon formation

6. Industrial Uses of Polyethene

• Plastic bags and bottles
• Car covers and wire insulation
• Water pipes and moisture barriers

7. Key Takeaways

✅ Plastic waste is a major environmental concern.

✅ Recycling is essential but has limitations.

✅ Polymerisation creates plastics through addition or condensation reactions.

✅ Industrial uses of plastics range from packaging to construction.