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These Pages include various standards. To confirm the status of any standard, identify the replacement standard if it is obsolete and/or purchase the standard please use. It is also possible to become a BSI member and obtain copies of the Standards at much reduced prices. |
Plastics Rubber Page Thermoplastics
ABS (AcronitrileButedeneStyrene Tough, stiff, abrasive resistant and can be metal plated. Good stain resistance
but are attacked by chlorinated solvents, esters, keytones and concentrated acids
and alkalis. Some greases can cause stress cracking.
The properties of ABS depend on the proportions of the three constituents. .
ABS can be injection moulded, extruded, rotationally moulded and thermoformed.
Typical applications include boat hulls, telephones, piping/fittings, and domestic
durables. Flexibility and properties depend on the nature and content of plasticisers.
Used for cable/wire insulation, soles of footwear, and coating linen liners of industrial
gloves. Hard/tough/ strong and stiff with good weathering properties. It is weather resistant and self extinguishing, can be transparent and the surface is scuff and abrasion resistant. UPVC can be extruded, injection moulded, blow moulded, rotationally moulded and thermoformed. It is mostly used for making pipe/pipe fittings, bottles, and window frames . Polyethylene Tough at low temperatures with excellent chemical and electrical insulation properties.
Detergents can cause stress cracking.
Can be extruded, injection moulded, blow moulded, rotationally moulded and thermoformed.
LDPE- Low Density Polyethylene(918-935 kg/m3 is very tough and flexible with excellent chemical resistance.
Used for pipes and low loss electrical wire coverings.
HDPE- High Density Polyethylene (935- 965 kg/m3 is much stronger and stiffer. It is used for tanks, pipes dustbins etc.
Excellent fatigue resistances, chemical and electrical properties. Good temperature resistance
and useful strength and stiffness. It is attacked by strong oxidising agents.
Can be extruded, injection moulded, blow moulded, rotationally moulded and thermoformed. AMORPHOUS THERMOPLASTICS Acrylics Completely transparent and optically clear. Stable to outdoor weathering and do not discolour
or degrade under UV light. Acrylics are stiff, strong and do not shatter. Some solvents can
cause stress cracking. Tough, transparent, stiff and strong. Good electrical insulation properties.
Polycarbonates have moderate outdoor weather resistance. Dissolved by chlorinated
paraffins, cresol,dioxane. Attacked by hydrocarbons. Strong, stiff with excellent creep and dimensional properties over a wide range of temperatures. Can be transparent. They do not easily burn and do not present a smoke hazard. They are attacked by ketones chlorinated solvents and hydrocarbons. They can be extruded, injection moulded and thermoformed. Polysulphanes are used for passenger service units in aircraft and electrical components requiring high service temperatures. CRYSTALLINE THERMOPLASTICS Nylon...Polyamines Nylon materials are stiff, strong,tough and abrasion resistant. Absorption of
moisture increases toughness, decreases stiffness and affects dimensional stability. Concentrated
mineral acid attacks nylon.
Nylon can be injection moulded, rotationally moulded and extruded.
Applications for nylons include insulators, and engineering components such as gears, bushes,
and bearings. Glass filled nylon is used to make power tool housings etc. Stiff, strong, resist high temperatures and are extremely resilient. These materials
are abrasion resistant and have low coefficient of friction. Polyacetals are attacked by
strong acids. Applications include pipe fittings, light-duty beam springs, meat hooks, gears,
bearings etc. This material has similar physical properties to nylon 66 but have much lower
moisture absorption. Is attacked by ethylene dichloride and is susceptible to hydrolysis
in prolonged contact with hot water. Processed by injection moulding. PTFE resists all common aggressive environments, has exceptional low coefficient of friction, first class electrical properties and can be used at temperatures up to 250 deg C. It can be processed only be a special sintering techniques. Complicated shapes are generally machined from sintered blanks. PTFE is used for bearings, bearing surfaces treatments, high frequency cable insulation, coating for cooking utensils etc etc. |
Links Providing information on Thermoplastics
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