thermoplastics Flashcards
what are thermoplastics made of?
Thermoplastics are made up of lines of molecules with few cross linkages. This allows them to soften when heated and to be bent into a variety of shapes and forms.
can thermoplastics be reheated and reshaped?
. They become stiff and solid again when cold. This process can be repeated many times.
what are thermoplastics suitable for?
They are suitable for Injection moulding, Vacuum forming, Blow moulding.
what is the most common plastic in a workshop?
acrylic
acrylics
It can be translucent (e.g. smoked), transparent (clear) or opaque (solid colour).
what is acrylic resistant to?
it is resistant to most acids and weather conditions
what are acrylics strengths and weaknesses
Ten times more impact resistance than glass. Splinters easily and scratches easily
what can acrylic be used for
It can be used for light units and illuminated signs, watch and clock glasses, simple lenses, aircraft canopies and windows, car rearlight units, skylights, furniture, baths, perspex sheet.
Polythene
Can be moulded into almost any form due to its excellent moulding qualities. Used for the production of bottles, bowls, toys, tube etc. It is available in large sheets. There are two types: High density which is rigid and hard and low density which is tough and
flexible. Machine parts are generally made from high density polystyrene whilst bottles are made from the low density polystyrene.
Polyvinyl Chloride. (Better known as PVC)
It is a tough material which can be purchased as a hard material or alternatively a flexible form. It can be welded or bonded with an adhesive. It has a range of uses including water pipes, raincoats, long play records, coating on electrical wires and many more.
