Chapter 27 – Review

27.1 Polymerization

1. Explain the difference between monomer and polymer.  Provide an example of each.
2. What is meant by the term “natural polymer”? “synthetic polymer”? Provide an example of each.
3. Which of the following is not a common natural polymer? Check answer^[1]
   1. Cellulose
   2. Starch
   3. Polyethylene
   4. DNA

27.2 Classification of Polymers

1. Explain the differences between thermosetting and thermoplastic polymers.  Provide an example of each.
2. Explain the differences between addition and condensation polymers.  Provide an example of each.
3. Why is the term plastic used to describe some but not all polymers?
4. Looking at a monomer, how could you predict if the polymer will be formed by addition polymerization or condensation polymerization?  Give at least two reasons.
5. What is the main characteristic of a thermosetting polymer? Check answer^[2]
   1. It can be melted and reshaped multiple times.
   2. It softens when heated and hardens when cooled.
   3. It undergoes irreversible chemical cross-linking when heated.
   4. It remains flexible at all temperatures.

27.3 Polyethylene

1. Why is polyethylene not a co-polymer? Check answer^[3]
2. Explain the similarities and differences between HDPE and LDPE.

27.4 Addition Polymerization

1. Draw the structural formula of the addition polymer created by the following monomers: a) ethene, b) 1-chloro-2-butene, c) bromoethene
2. Which monomer is primarily used in the synthesis of polyvinyl chloride (PVC)?  Check answer^[4]
   1. Ethylene
   2. Propylene
   3. Vinyl chloride
   4. Acrylonitrile
3. Which polymer is commonly used in making non-stick cookware due to its low coefficient of friction? Check answer^[5]
   1. Polyethylene
   2. Polypropylene
   3. Polystyrene
   4. Polytetrafluoroethylene (PTFE)
4. Which polymer is commonly used in the production of disposable food containers and packaging materials? Check answer^[6]
   1. Polystyrene
   2. Polyethylene terephthalate (PET)
   3. Polyurethane
   4. Polybutadiene

27.5 Rubber and Other Elastomers

1. What are some of the benefits of the vulcanization of rubber process?
2. What were some of the drivers and impacts of the discovery of rubber?
3. Why are there geometric isomers of some polymers and not others? What is special about those polymers that can have geometric isomers?

27.6 Condensation Polymers

1. Which synthetic polymer is used in the production of clothing and textiles? Check answer^[7]
   1. Polyethylene
   2. Polypropylene
   3. Polyester
   4. Polyvinyl chloride (PVC)
2. What is the primary use of polyurethane foam in construction and manufacturing? Check answer^[8]
   1. Insulation
   2. Transparent windows
   3. Structural support beams
   4. Electrical conductivity

27.7 Properties of Polymers

1. List the four factors that influence a polymer’s physical properties.  Describe how each affects the polymer.

27.8 Plastics and Recycling

1. Do polymers need to be reduced to their monomers for recycling? Why or why not?
2. Describe some of the challenges associated with recycling plastics.
3. Research the recycling process in your local municipality.  What plastics are accepted? What are not?  How are the plastics recycled?
4. Research what is required in a waste audit.  Conduct a mini waste audit of your household focusing on recyclable materials.  What can you summarize about your household’s plastic usage?
5. What changes are coming to the recycling program in Canada/Ontario? Research will be required.
6. Do you think it is easier to recycle a thermosetting or thermoplastic polymer? Why?
7. You have a neighbour who insists on putting all plastic materials in the recycling bin.  Explain to the neighbour why only certain plastics can be recycled.

27.9 Plastics and the Environment

1. What is the primary function of a plasticizer in polymer formulations? Check answer^[9]
   1. Increase the melting point of the polymer
   2. Enhance the electrical conductivity of the polymer
   3. Improve the polymer’s mechanical strength
   4. Increase the flexibility and ease of processing of the polymer
2. What is the primary environmental impact of plastic pollution in oceans? Check answer^[10]
3. How does plastic pollution affect terrestrial ecosystems? Check answer^[11]
4. What role does microplastic pollution play in environmental degradation? Check answer^[12]
5. What is the long-term impact of plastic accumulation in landfills? Check answer^[13]
6. How can reducing single-use plastics benefit the environment? Check answer^[14]
7. What is the Pacific Garbage Patch, and what are its environmental consequences? Check answer^[15]

Overall Thinking

1. Pick an item that is made of a polymer.  Do some research to find out which polymer it is made of.  If possible, sketch a skeletal drawing of the polymer.
2. Some of the data provided about various polymers in this chapter is US based.  Pick one of the polymers and research it’s use and production in Canada.  Are the numbers similar? Are their different legislations regarding its use?

Attribution & References

Except where otherwise noted, “Chapter 27 – Review” was written by Samantha Sullivan Sauer, CC BY-NC 4.0

References

Hein, M., Pattison, S., Arena, S., & Best, L. R. (2014). Introduction to General, Organic, and Biochemistry (11th ed.). Wiley.