Smart materials

Question 1

Thermochromatic pigment

Answer 1

Thermochromatic pigment is mixed with acrylic [acrylic: A type of plastic; also a water-soluble, polymer-based paint. ] paint. At room temperature it shows its usual colour, but when heated above 27°C the colour changes to black.

Question 2

Phosphorescent pigments

Answer 2

Phosphorescent pigments glow in the dark, first absorbing light and then emitting it.

Question 3

Thermocolour sheet

Answer 3

Thermocolour sheet is a material printed with thermochromic pigment which changes colour as the temperature changes.

Question 4

Polymorph

Answer 4

Polymorph is a plastic that becomes mouldable at 62°C. It is used for product-modelling [product-modelling: Creating a product-design model. This is a three-dimensional model that won’t work, but does show the form and finish of the end-product. As well as plastics, product-design models can be made from wood or foam blocks. ], curves (eg handles), and moulds for vacuum-forming [vacuum-forming: A process that makes 3D forms made from flat thermoplastic sheet. The plastic sheet is clamped over the mould and is heated. Air is removed from the void under the sheet. This causes the plastic to form over the mould. ].

Question 5

High-density modelling foam

Answer 5

High-density modelling foam is available in blocks. It can be shaped using hand and machine tools and takes fine detail well. It is often used on CNC [CNC: Stands for Computer Numerical Control - the use of computers to control cutting and shaping machines. A key CAM (computer-aided manufacturing) technique. ] milling machines.

Question 6

Precious Metal Clay (PMC)

Answer 6

Precious Metal Clay (PMC) is made from 99% gold or silver and 1% clay. It can be shaped at room temperature, then heated. It’s very expensive and mainly used for jewellery.

Question 7

Cornstarch polymer

Answer 7

Cornstarch polymer is used to replace oil-based thermoplastics in packaging. It is made from high starch vegetables including potatoes, corn and maize. It is biodegradable

Question 8

Paperfoam

Answer 8

Paperfoam is made from starch-based fibres and paper fibres. It is scratch resistant, can be moulded, and is used for shaped inserts in packaging. It is biodegradable.

Question 9

Potatopak

Answer 9

Potatopak is made of potato starch. It is used for biodegradable disposable trays, plates, bowls, cups and containers. After use it can be composted, used for pig food or worm food