Smart materials

Question 1

what is a smart material?

Answer 1

a material that has at least one property that changes reversibly when their environment changes in a certain way.

Question 2

shape-memory alloys

Answer 2

metal alloys which return back to the original shape when heated. e.g. surgical wires

Question 3

example of a shape-memory alloy

Answer 3

surgical wires

Question 4

thermochromic pigments

Answer 4

change colour when reaching a certain temperature

Question 5

example of a thermochromic pigment

Answer 5

thermometers, bath toys, colour changing mugs

Question 6

photochromic pigments

Answer 6

change colours with light intensity

Question 7

example of photochromic pigments

Answer 7

dyes in clothing, lenses in glasses that darken in bright sunlight

Question 8

shape memory polymers

Answer 8

plastics that return back to their original shape when heated

Question 9

example of a shape memory polymer

Answer 9

gumsheilds

Question 10

hydrogels

Answer 10

polymers that can absorb up to 1000 times their own volume in water and can also reeasethe water they released when in dry conditions

Question 11

how do hydrogels work

Answer 11

they swell up allowing water molecules to join weakly to the polymer chains

Question 12

example of a hydrogel

Answer 12

filing of nappies