Plasticisers & Hardeners

The lesson explores the roles of plasticizers and hardeners in modifying polymer properties. Plasticizers make polymers like PVC softer and more flexible by reducing intermolecular forces, while hardeners or crosslinking agents increase rigidity and strength. The video discusses the applications and safety concerns of these additives, such as the potential carcinogenic nature of some plasticizers and the environmental impact of vulcanized rubber. Examples include the use of plasticized PVC in raincoats and UPVC in window frames, and the vulcanization of rubber for tires.

What is a common use of unplasticized PVC (UPVC)?

• Rain boots

• Wiring insulation

• Window frames

• Raincoats

How do plasticizers affect the intermolecular forces in polymers?

• They decrease the forces

• They have no effect

• They increase the forces

• They make the forces stronger

What is a potential health concern associated with some plasticizers?

• They cause corrosion

• They are flammable

• They are known carcinogens

• They can cause allergies

What is the role of a hardener in a polymer?

• To make it softer

• To make it more flexible

• To make it more transparent

• To make it stronger and more rigid

What process involves adding sulfur to rubber to increase its strength?

• Distillation

• Cracking

• Vulcanization

• Polymerization

What is the main environmental concern when burning rubber?

• Release of carbon monoxide

• Formation of sulfur dioxide

• Production of nitrogen oxides

• Emission of methane

What is the primary difference between the effects of plasticizers and hardeners on polymers?

• Plasticizers and hardeners have the same effect on polymers

• Plasticizers make polymers softer, while hardeners make them more rigid

• Plasticizers make polymers more rigid, while hardeners make them flexible

• Plasticizers make polymers harder, while hardeners make them softer