Ceramics, Polymers & Composites

Science · Matter & Materials · ages 13-14

Name ______________________ Date ____________

Which of these is a synthetic polymer?
- Silk
- Nylon
- Cotton
Which set of properties best describes a ceramic material?
- Hard, brittle, and heat-resistant
- Soft, stretchy, and light
- Bendy, waterproof, and cheap
A composite material combines two or more materials to get properties neither has alone.
Circle one: True False
Wool grows on sheep and is later spun into yarn. Is it a natural or synthetic polymer?
- Natural, because it comes from sheep
- Synthetic, because it's manufactured into clothing
- It's a ceramic, not a polymer
Why is carbon-fibre reinforced plastic used for racing bike frames instead of pure carbon fibre?
- Pure carbon fibre bends too easily under weight
- Pure carbon fibre is too heavy for a bike
- Pure carbon fibre is too brittle and could snap suddenly
A factory changes a polymer's chain length to make a rubber band stretchier. What does this show?
- Polymers can't be changed once they are made
- Polymer properties can be tailored by changing their chemical structure
- Only metals can be shaped during manufacturing
An engineer needs a light material for a plane wing that resists bending and heat. Why might a composite beat a ceramic or polymer alone?
- A composite can combine a ceramic's heat resistance with a polymer's flexibility
- A composite is always the cheapest option available
- A composite is always heavier than metal
Tom says a window is a composite because glass is strong. Is Tom correct?
- Yes, glass always contains carbon fibre
- Yes, all hard materials are composites
- No, glass alone is a ceramic, not a mix of materials

Answer key

For grown-ups. Fold this page away before handing over the rest.

Ceramics, Polymers & Composites W1-mt_w83U-_noVR-s1

Nylon · Nylon is made in a factory from chemicals, so it's synthetic. Silk and cotton are natural polymers.
Hard, brittle, and heat-resistant · Ceramics like pottery and bricks are hard and can take high heat, but they crack instead of bending.
True · That's exactly what a composite is, like carbon fibre and resin combined.
Natural, because it comes from sheep · Wool grows naturally on sheep, so it's a natural polymer. Spinning it into yarn doesn't make it synthetic.
Pure carbon fibre is too brittle and could snap suddenly · Carbon fibre alone is strong but brittle. Mixing it with resin stops sudden cracking.
Polymer properties can be tailored by changing their chemical structure · Changing chain length or adding chemicals during manufacturing changes how a polymer behaves.
A composite can combine a ceramic's heat resistance with a polymer's flexibility · Composites let engineers mix materials to get strength, heat resistance, and light weight together, something no single material offers alone.
No, glass alone is a ceramic, not a mix of materials · A single material like glass, even though hard, is a ceramic on its own. A composite needs two or more materials combined.