D. Answer the following questions in detail.
1. State two properties and two uses of rayon.
2. What are the uses of polyester?
3. List the advantages of synthetic fibres.
4. Explain any two characteristics of plastic.
5. How are plastic bags a threat to animal life?
Answers
Answer:
1. Rayon is a versatile fiber
• Rayon is very soft, cool comfortable and very good absorbent property but could not be able to protect body heat and used in humid steamy climatic conditions.
2. Clothing, Trousers, Film, Jacket, Shirt, Home Furnishing, insulation, car tire reinforcement, computer mouse mat, safety belt, Filter, Package cushioning, Conveyor belt, Liquid-crystal display, Holography, Bottle, Canoe, Tarpaulin, Upholstery, Rope, Sheet, Blanket and Hat.
3. Synthetic fibres are very durable and do not wrinkle easily.
They are elastic and can be easily stretched out.
They are strong and can sustain the heavy load.
They are soft and hence used in clothing material.
They are cheaper than compared to natural fibres.
4. Plastics generally have: resistance to corrosion and chemicals, low electrical and thermal conductivity, high strength-to-weight ratio, colors available in a wide variety and transparent, resistance to shock, good durability, low cost, are easy to manufacture, resistant to water and have low toxicity.
5. In the case where the limbs of animals are trapped, it makes them less agile and more vulnerable to predators, competitors, and environmental stress. If they manage to eat the plastic, it can also cause intestinal blockages and can become fatal for that animals.