3.2 Smart And Modern Materials

Question 1

What are smart and modern materials

Answer 1

Materials whose properties alter depending on environmental conditions such as light, temperature of movement.

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Question 2

Properties and uses of SHAPE MEMORY ALLOT (SMA) or NITINOL

Answer 2

Properties: alloy composed of nickel and titanium. Will return to its original shape when bent and heated to 90 degrees. Contracts when an electric current is passed through.

Uses: used in stents (tubes inserted into damaged blood vessels) also used in some spectacle frames or in dentures

Question 3

Shape memory polymer (SMP)

Answer 3

Properties: deform in response to an external stimulus (eg when an electric voltage is applied or there is a change in temp.)

Uses: valves or pumped for liquids where mechanical components are undesirable

Question 4

Thermochromic inks

Answer 4

Properties: change colour in response to changes in temperature

Uses: forehead thermometer strips and in food industry to indicate the temperature of a packaged food product

Question 5

Photochromic inks

Answer 5

Properties: change colour in response to changes in light level (including UV or infrared IR)

Uses: light reacting sunglasses which looks darken in response to UV light

Question 6

Lenticular sheet

Answer 6

Properties: optical properties which make the surface appear deeper. Different kinds which make images appear to Flicker it move.

Uses: provide visual aesthetic interest to a surface (3D effects)

Question 7

Polymorph

Answer 7

Properties: available in small pellets which fuse when heated to 62 degrees and can be moulded. Resulting in a tough polymer.

Uses: used by engineers to prototype difficult shapes such as components, joints and handles.

Question 8

Smart Grease

Answer 8

Properties: viscous gel which will uniformly control the movement between two friction surfaces.

Uses: to dampen movement in volume control knobs - slowing down and smoothing rotation

Question 9

KEY TERMS

Biomimicary

Answer 9

An approach to innovation and design that takes inspiration from how nature solves problems

Question 10

Memory:

Answer 10

The property by which a material returns to its original shape under specific environmental conditions.

Question 11

Nanoparticles

Answer 11

Between 1 and 100 manometers and material where the structure has been engineered at the nanoscale can have unique properties. Eg graphene

Question 12

Polymer

Answer 12

A substance comprised of large molecules made up of simple molecules of the same kind. Eg acrylic plastic and polythene.

Natural polymers: silk, wool and cellulose