1. 1
   A materials company is developing new polymer-based products for packaging, clothing and medical applications.

   (a)

   Which of these is a use of polymers described in the specification?

   [1 mark]

   • AAs a waterproof coating for fabrics
   • BAs a catalyst for cracking hydrocarbons
   • CAs a fuel for vehicle engines
   • DAs an indicator in acid–base titrations

   (b)

   What is meant by a 'smart material' such as a shape memory polymer?

   [1 mark]

   • AA material that can return to a particular shape when a stimulus, such as heat, is applied
   • BA material that dissolves instantly in water at any temperature
   • CA material that is always transparent
   • DA material that conducts electricity like a metal

   (c)

   State two other uses of polymers, besides packaging and waterproof coatings, that this company might develop.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   A packaging manufacturer compares low-density poly(ethene) (LDPE), used for plastic bags, and high-density poly(ethene) (HDPE), used for rigid bottles, both made from ethene monomer.

   (a)

   Low-density poly(ethene) (LDPE) and high-density poly(ethene) (HDPE) are both made from the same monomer, ethene, but have different properties. What is mainly responsible for this difference?

   [1 mark]

   • AThey are made using different catalysts and conditions
   • BThey are made from completely different monomers
   • CLDPE contains added sulfur and HDPE does not
   • DHDPE is not a polymer at all

   (b)

   Which of the two polymers, LDPE or HDPE, is generally more rigid and used for products such as bottles?

   [1 mark]

   • AHDPE
   • BLDPE
   • CNeither is rigid
   • DBoth are equally rigid

   (c)

   Explain why the properties of a polymer such as poly(ethene) can vary, even though it is always made from the same monomer.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   A polymer chemist is advising several industries, including packaging, medicine and construction, on which types of polymer are best suited to different applications.

   (a)

   A medical company wants to develop a hydrogel wound dressing. Explain why a hydrogel is a suitable polymer for this use.

   [3 marks]

   (b)

   Explain, using LDPE and HDPE as examples, how varying the starting materials and production conditions used to make polymers allows manufacturers to produce polymers with different properties for different uses.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   A science communicator is writing an article explaining to the public why polymers are used in so many everyday and specialist products, from packaging to medicine.

   (a)

   Discuss the wide range of uses of polymers, including packaging materials, waterproof coatings, dental polymers, wound dressings, hydrogels, and smart materials, explaining why polymers are suitable for each type of application.

   [6 marks]

   (b)

   Explain how the properties of a polymer depend on what it is made from and the conditions under which it is produced, using LDPE and HDPE as an example, and explain why this matters when selecting a polymer for a specific application.

   [6 marks]

   Total for question 4: 12 marks

End of questions