Slides in this set
There are two main groups of plastics:
· thermosetting plastics The word
· thermoplastic plastics. What does
Formed by heat
Soften when heated
Made of long
with few cross links
Can be reheated
Mostly recyclable…read more
Thermoplastic plastics are made of long chains of polymers
which don't cross over very often. When heated, the molecules
slip easily over one another.
Thermosetting plastics also have lots of long chain molecules,
but there are links between them. These cross links prevent the
molecules from moving over one another.
individual monomer molecule individual monomer molecule
Which of these diagrams depicts a thermoplastic
and which depicts a thermosetting plastic?…read more
The majority of common plastics are thermoplastics.
· Thermoplastics can be heated and reshaped because of the
ways in which the molecules are joined together.
· This can be repeated many times (as long as no damage is
caused by overheating).
Thermosetting plastics are those which are set with heat and
have little elasticity. Once set, they cannot be reheated and
· They are heated and moulded Burn
· Once cooled, they will not
soften again when heated. Heat
This breaks the potentially
unending cycle that Harden
thermoplastic plastics are Soften
· If heated too much, they burn. Cool…read more