Thermosetts
Polyester Resin
: A clear hard resin - brittle unless it is reinforced with
glass matt.
Common applications :
It can be cast and is used for embedding small objects, e.g.
in jewelry. When used in conjunction with glass matt it is called (GRP)
Glass Reinforced Polyester resin which is very strong. It can be moulded
into very complex forms which are then tough and resist splitting. It is
used for boat hulls and car bodies etc.
Common forms :
Liquids or pastes
Epoxy Resin
: Has exceptional adhesive qualities. Low shrinkage rate,
high strength when reinforced
Common applications :
As a bonding agent, encapsulation, surface coating laminating
Common forms :
Liquids or pastes
Melamine Formaldehyde
: It has a very hard tough surface which is highly
resistant to ignition.
Common applications : Used as a thin laminate to finish
man-made boards. A very useful material which transforms inexpensive
man-made boards, especially chipboard, into attractive hygienic and
useful materials.
Common forms :
Powder, granules, laminates
Phenolic Resin : A
strong, hard and rigid thermosett. It is usually black or brown in
colour.
Common applications :
Pan handles, Knobs, Electrical switch covers, electrical
appliances
Common forms :
Powder, granules, reinforced laminates
Thermoplastics
Most of these materials are available in sheet form
(which can usually be vacuum formed) and in granules (for injection
moulding). Although many types will not float, they are usually referred
to as light materials, this is primarily because they are used in small
quantities or in very thin sheets. Commonly used examples are:
ABS
: Very tough, high impact strength.
Common applications :
boat hulls and model car bodies.
Common forms :
Powders, granules, wide range of colours.
Nylon
: Engineering plastic - Hard, very tough, rigid and wear
resistant (it is self lubricating) High melting point. It machines well
and is good for bearings.
Common applications :
power tool casings, gear wheels, curtain rail fittings, clothing
Common forms :
Powder, granules, rod, tube, sheet - usually white or off white but
other colours available.
PVC
: Stiff, hard and tough at room temperature. Very good acid
and alkali resistance..
Common applications :
pipes gutterings, bottles and containers, shoe soles.
Common forms :
Powder, pastes, sheet - wide range of colours available.
Polypropylene
: Strong and tough, light, floats, is flexible and is not
affected by boiling water or chemicals.
Common applications :
crates, chair shells, waste and chemical pipes, packaging film, string,
rope and sacks, car bumpers, syringes, containers with integral hinges.
Common forms :
Powder, granules, rod, tube, sheet - usually pale pink or off white but
can be pigmented.
Polystyrene
: As thin sheets - stiff, hard and inexpensive
Common applications :
Food containers, disposable cups, cutlery, plates. Model kits,
refrigerator linings, kitchenware, toys, electrical equipment cases.
Common forms :
Powder, granules, sheet - wide range of colours available.
Expanded Polystyrene
: very light and bouyant. absorbs shocks. A good sound and
heat insulating material.
Common applications :
sound and heat insulation, packaging.
Common forms :
sheets, slabs, beads - usually white.
Acrylic (PMMA)
: A hard, stiff material, but farly brittle material. Very durable
outdoors, easily machind, cemented and polished. Good electrical
resistance, safe with food. Splinters and scratches easily.
Common applications :
light units and illuminated signs. Lenses, windows, rear light covers,
skylights, baths.
Common forms :
rod, tube, sheet - can be clear, translucent or opaque a wide range of
colours available.
Polythene
: Tough, good chemical resistance, good electrical insulator,
flexible and soft. Hardness, stiffness and impact resistance increases
with density. Attracts dust unless anti-static.
Common applications :
squeezee bottles, plastic sacks and bags, cling film, wire and cable
insulation. In its high density form it is used for bottles, barrels,
tanks, buckets and bowls.
Common forms :
Powder, granules, films, sheet - wide range of colours available.
In What Forms are Plastics available ?
Plastics are available in a wide variety of forms.
Not all types of plastic are available in every form and it is almost
certain that only a few types will be available in school. Look at a
catalogue for more accurate details, but an idea of the variety is shown
below.
