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• Ceramics are made by baking substances to produce a brittle, stiff material
• Clay Ceramics - a mineral formed from weathered and decomposed rock:

  • soft when dug up (easy to mould)
  • hardened by firing at very high temperatures
  • ideal building material (withstand lots of weight)

  Glass Ceramics - generally transparent and strong (e.g. windows)

  • moulded when hot
  • brittle when thin
  • made by heating limestone, sand and sodium carbonate until it melts together into soda-lime glass
• Ceramics are insulators of heat and electricity. They're much more brittle/stiff than other materials but are strong, hard-wearing and don't degrade or corrode
• Metal as a material:

  • good conductors of heat/electricity
  • high density
  • malleable
  • mixed to form alloys
  • can be corrosion resistant
  • less brittle (will deform instead of shatter)
• Composite materials, such as fibreglass and concrete, are made of 2 materials; one material as the matrix and the other as the reinforcement inside the matrix. Properties vary on materials used
• Composite Material Carbon Fibre:

  • made using carbon atoms bonded together to make carbon fibres/nanotubes hold together in a polymer resin matrix
  • expensive
  • light
  • strong
  • ideal for aerospace and sports car manufacturing
• Composite materials can be designed to have specific properties for a specific purpose based on the materials used for the matrix and reinforcement
• Nanoparticles are made of a few hundred atoms and so are bigger than simple molecules. They're usually 1 to 100 nanometres long where one nanometre is one billionth of a metre
• Fullerenes are nanoparticles. They include nanotubes which are tiny hollow carbon tubes held together by very strong covalent bonds. Fullerenes have different properties from the bulk chemical carbon
• Nanoparticles have a large surface area to volume ratio because of their tiny size, meaning there are different properties caused by greater proportions interacting with contacted substances
• Nanoparticles can modify properties of materials (nanoscience) which develops new uses: (1)

  • huge surface area to volume ratio makes them good catalysts - more collisions equal a faster rate of reaction
  • new cosmetics - sunscreens provide better protection and are invisible
  • nanomedicine - absorbed more easily so drugs can be delivered
  • lubricant coatings - gears/artificial joints
• Nanoparticles can modify properties of materials (nanoscience) which develops new uses: (2)

  • nanotubes conduct electricity - electric circuits for computer chips
  • nanoparticles added to plastics in sports equipment - plastic stronger and more durable without adding much mass
  • silver nanoparticles on polymer fibres - antibacterial properties to surgical masks and wound dressings
• Disadvantages of Nanoparticles:

  • side-effects and long-term impacts are unknown
  • short term testing may not protect human health
  • cause lung inflammation when breathed in
  • catalyse harmful reactions
  • build up in cells as they don't break down easily
  • can be absorbed through skin