15-Polymer Processes

Question 1

Polymer Processes - Vacuum Forming

Answer 1

• Thermoplastic sheet stock form
• Heating a plastic sheet until soft and then draping it over a mould. A vacuum is applied sucking the sheet into the mould. The sheet is then ejected from the mould.

Question 2

Polymer Processes - Thermoforming

Answer 2

• Thermoplastic sheet stock form
• Like Vacuum forming but an additional mould is pressed onto the surface of the polymer

Question 3

Polymer Processes - Line Bending

Answer 3

• Provides heat in a straight line so the polymer can be bent
• Used mainly in schools for one off production

Question 4

Polymer Processes -Calendering

Answer 4

• Heated rollers continuously squash and stretch polymers to make them thinner

Question 5

Polymer Processes - Lamination

Answer 5

• The bonding of two or more layers of materials using heat, pressure and an adhesive.
• Requires a former to mould around

Question 6

Polymer Processes - Injection Moulding

Answer 6

• Thermoplastic granules travel from the hopper to the archimedian screw.
• The granules are melted here and pushed by the screw into a mould
• Used in industrial settings

Question 7

Polymer Processes - Blow Moulding

Answer 7

• A parison (tube) of polymer is placed within a mould
  The parison is then blown into so the polymer tube will expand to the walls of the mould
• Used to create hollow, thin walled components

Question 8

Polymer Processes - Rotational Moulding

Answer 8

• Polymer powder/granules are placed into a mould
• The mould is then heated to melt the polymer and rotated
• This spreads a layer of the polymer all around the mould creating a seamless hollow component

Question 9

Polymer Processes - Extrusion

Answer 9

• Similar to injection moulding however instead of the molten polymer being pushed into a mould it is pushed through a die and carried out on a conveyor belt in order to produce extended lengths of polymer

Question 10

Polymer Processes - Compression Moulding

Answer 10

• Preheated polymer known as a ‘slug’ is placed into the lower mould
• A compressive hydraulic press will then be lowered onto the ‘slug’ to form the polymer to the shape of the mould.
• Both halves of the mould are heated throughout the process and the polymer is removed while still warm