18.3.1 Addition Polymers

• How are addition polymers formed?

  Chain reaction of monomers
• Addition polymers contain carbon-carbon double bonds in their monomers

  True
• What is the repeating unit of an addition polymer identical to?

  The monomer
• Monomers needed for addition polymers must contain carbon-carbon double bonds
• Styrene is used to form polystyrene through chain-growth polymerization


  True
• In the initiation step of addition polymerization, free radicals react with monomers
• Different side groups on the monomer affect the properties of the polymer.

  True
• Match the addition polymer with its monomer:

  Polyethylene (PE) ↔️ Ethene (Ethylene)

  Polypropylene (PP) ↔️ Propene (Propylene)

  Polystyrene (PS) ↔️ Styrene
• What are the properties of polyethylene (PE)?

  Flexible, durable
• Polypropylene (PP) is stronger and more heat-resistant than polyethylene.
• What are the properties of polystyrene (PS)?

  Rigid, brittle
• Arrange the steps in the formation of addition polymers:

  1️⃣ Monomers containing carbon-carbon double bonds are used

  2️⃣ Polymerization occurs through a chain reaction

  3️⃣ Repeating units identical to the monomer form the polymer structure
• Polypropylene (PP) is used in ropes, carpets, and automotive parts.
• What is polystyrene (PS) commonly used for?

  Disposable cups, packaging, insulation
• What is polyvinyl chloride (PVC) known for?

  Durable, resistant to chemicals
• Addition polymers are formed by monomers containing carbon-carbon double bonds
• The polymerization of addition polymers follows a chain-growth mechanism
• Match the addition polymer with its example:

  Polyethylene ↔️ PE

  Polypropylene ↔️ PP

  Polystyrene ↔️ PS
• What is the structure of ethene, a common monomer for addition polymers?

  $CH2 =$$CH2$
• Steps in the polymerization process of addition polymers

  1️⃣ Initiation: Free radicals are created by an initiator

  2️⃣ Propagation: Free radicals add more monomers to the chain

  3️⃣ Termination: Free radicals combine, stopping chain growth
• What happens during the propagation step of addition polymerization?

  Free radicals add monomers
• Addition polymers consist of repeating units identical to the monomer

  True
• What affects the properties of addition polymers, such as flexibility and strength?

  Side groups
• Polyethylene, formed from ethene, is known for its flexibility
• Polypropylene is stronger and more heat-resistant than polyethylene


  True
• What type of bonds must monomers have to form addition polymers?

  Carbon-carbon double bonds
• The monomers in addition polymerization add to each other in a chain reaction.
• What is the repeating unit in the structure of an addition polymer identical to?

  The monomer
• What are the uses of polyethylene (PE)?

  Plastic bags, containers, pipes
• The repeating units in addition polymers are identical to their monomers.
• What is the main characteristic of monomers used in addition polymerization?

  Carbon-carbon double bonds
• Addition polymers undergo chain-growth polymerization.


  True
• Match the property with its description in addition polymers:

  Monomer Structure ↔️ Contains C=C double bonds

  Polymerization ↔️ Chain-growth process
• To form addition polymers, monomers must contain carbon-carbon double bonds.
• What is the polymer product of ethene (ethylene)?

  Polyethylene
• The polymer product of propene (propylene) is polypropylene.
• Arrange the steps in the polymerization process of addition polymers:

  1️⃣ Initiation: Free radicals react with monomers

  2️⃣ Propagation: Free radicals add more monomers

  3️⃣ Termination: Free radicals combine, stopping chain growth
• The initiation step in addition polymerization creates free radicals.


  True
• During propagation, free radicals add more monomers to the growing polymer chain.
• Match the addition polymer with its property:

  Polyethylene ↔️ Flexible

  Polypropylene ↔️ Heat-resistant

  Polystyrene ↔️ Rigid