Plastics Flashcards
What is plastic memory
Each time a plastic is reheated it will attempt to return to its original flat shape
What are thermoplastics made from
Line of molecules with a few cross linkages
What are plastics
Man made and have taken the place of traditional materials like wood and glass
What are some plastics derived from
Animals ,insects and plants
Where do most synthetic plastics come from
Crude oil but coal and natural gasses are also used
What is the process of polymerisation
Gasses are broken down into monomers which is a substance containing a single molecule. Thousands are linked together to form new compounds
What are the two main types of plastics
Thermoplastics and thermosetting plastics
What are thermosetting plastics made from
Lines of molecules which are heavily cross linked it creates a rigid molecular structure
Thermoplastic have a few cross linkages which allows them to do what when heated
Soften when heated and to be bent into a variety of shapes and forms
What are thermoplastics suitable for
Injection moulding, vacuum forming, blow moulding
What is acrylic also know as
Perspex
How can acrylic be purchased
In the form of sheets and can come in a range of colours
What colour can acrylic come in
Translucent e.g smoked
Transparent e.g clear
Opaque e.g blue
What can polythene do due to its excellent moulding quality
Can be moulded into almost anything
What are the difference in the two types of polythene sheets
One is high density which is rigid and hard. Low density which is tough and flexible.
What can polyvinyl be purchased as
A hard of flexible form
What are thermosetting plastics ideal for
Sauce pan handles and plugs kettle handles
What is polyurethane good for and why
Basis of paint pots because it’s tough and its water resistant qualities
What are melamine formaldehyde used for
In the production of plastic laminates because of its smoothie surface and hygienic qualities
What is polyester resins also known as and used for
Glass reinforced plastics (GRP) it’s used for car body repairs, sailing boats, corrugated sheets because of its lightness nod toughness and resistance to water
