We might not realise it, but smart materials are starting to make a real impact on everyday life. Kettles that change colour when they boil Garments that plug into MP3 players Batteries that ‘report’ their condition These are all examples of the application of new materials exhibiting ‘smart’ behaviour.

You can get special materials that can change in different conditions.

Smart materials react to their environment Smart materials change their properties in response to heat, light, or something else (depending on the material) They often change back to their original state when the heat or light (or whatever else affects them) is taken away Some smart materials can let you make totally new products

Smart plastics do all sorts of cool stuff Polymorph (or polycaprolactone) is a type of smart plastic used for making models to try out new designs Its low melting point (62˚) means it can be made mouldable by immersing it in hot water If you overheat Polymorph you will ruin it Polymorph can be moulded and shaped by hand when warm, or machined when cold When fully cooled, it is stiff and strong (a bit like HIPS)

Moulding plastic parts Creating intricate shapes, like this mask For making handles/grips Completing complex assemblies Jewellery and decorations

It’s not just ‘Silly Putty’, this material has serious engineering applications! Soft mouldable plastic (like chewing gum) Instantly becomes a rubber if impacted; it bounces like a ball Can keep shape, stretch, absorb shock and deflect an applied load

Thermochromic pigments change colour with heat Thermochromic pigments change back to their original colour when they cool They can be used in paints to create images that change when they get hot Thermochromic inks can be printed onto a range of materials, such as plastic and paper Thermochromic films are sheets that have been printed with thermochromic ink - you could use them for displays that change colour when touched

Interesting gimmicks! Useful for marketing materials 2D heat-sensitive temperature gauge Has your egg been hot enough for long enough? Changes colour when food is too hot for a baby's mouth. Smart inks change colour with temperature

Photochromic pigments change colour in response to light Photochromic pigments change colour reversibly in response to light They can be put into spectacle lenses to make glasses that turn into sunglasses when it is sunny, and used to make the glass in buildings more energy efficient Photochromic inks can be used to print t-shirts with designs that only show up in sunlight

Lenses become darker with increased exposure to UV light (sunlight) MINI’s ‘Rainbow’ paint options gives a rainbow effect in bright sunlight Colour changing wristbands indicate when sun cream needs to be re-applied, or when it’s time to move into the shade Glass changes from transparent to opaque as level of light increase, saving energy Photochromic inks used to print t-shirt designs that only show up in sunlight

Phosphorescent glow in the dark Phosphorescent pigments store light and slowly release it, so they glow in the dark. Fluorescent pigments are really bright because reflect lots they reflect lots of light absorb UV light extra visible light of light. As well as reflecting visible light, they absorb UV light and reflect it as extra visible light – this is what makes them so bright.

Nanotechnology involves really, really, really, really, really, tiny particles (nanoparticles) Nanoparticles include tiny crystals and tiny tubes Nanotechnology has produced a wide range of clever ‘nanostructured’ materials because nanoparticles change the properties of the ‘normal’ material Nanocomposites are made by combining nanoparticles with existing materials

Nanoparticles are used to make anti-vandal paint (other paint won’t stick on top) Packaging materials can be made where the minute gaps in the product’s structure are filled with really tiny bits of ‘clay’ (nanoclays), making them extra airtight so food and drink lasts longer A mixture of nanotubes and carbon-fibre are used to make bike frames and tennis rackets that are very strong but also very light Nanotechnology is used in cosmetics, sunscreens and some medicines (nanomedicines) The use of nanotechnology is being developed to produce more effective medicines (‘smart’ drugs)

Nanoparticles are so tiny, that you could fit about a thousand of them into the width of just one of this dog’s hairs Nanoparticles under a microscope Nanotubes combined with carbon-fibre are used to make bike frames and tennis rackets that are extremely strong and lightweight Nano-silver has powerful antibacterial properties

Nanomaterials have useful properties, but some people are worried about the safety of nanotechnology – it is so new that it is difficult to know what the risks are. They are worried that nanoparticles might react with body chemicals and cause harm, or cause damage to the environment. OR ?