Ceramics, Polymers & Composites Flashcards

All 6 cards in this deck

What is soda-lime glass made from, and what is borosilicate glass made from?

Soda-lime glass: sand, sodium carbonate and limestone heated together. Borosilicate glass: sand and boron trioxide, and it melts at a higher temperature than soda-lime glass.

What are the steps to make a clay ceramic?
e.g. a brick or a pottery plate

1. Shape the wet clay.
2. Heat it in a furnace (kiln) — this is called firing.

How can both low density (LD) and high density (HD) poly(ethene) be made from the same monomer, ethene?

By using different reaction conditions (different temperatures, pressures and catalysts).
HD poly(ethene) has unbranched chains that pack closer together, so it is denser.

What is the difference in structure between thermosoftening and thermosetting polymers?

Thermosoftening polymers are separate chains held by weak intermolecular forces, so they melt when heated; thermosetting polymers have cross-links between chains, so they do not melt.

What is a composite, and what are its two parts called?

A material made of two materials: a matrix (binder) surrounding and binding together fibres or fragments called the reinforcement.
e.g. carbon fibres (reinforcement) in polymer resin (matrix); also concrete and fibreglass.

True or false? Metals generally have higher melting points and conduct heat better than polymers.

True. That is why saucepans are made of metal but their handles are made of polymer.