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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.

(Plasticised) PVC (PolyVinylChloride

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.

(UnPlasticised) UPVC (PolyVinylChloride

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. UPVC can be extruded, injection moulded, blow moulded, rotationally moulded and thermoformed. It is mostly used for making pipe/pipe fittings, bottles, and curtain rails.


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.

Polypropylene

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.
Acrylics can be extruded, injection moulded, and thermoformed. The are used for viewing panels, light housings, lenses and illuminated signs.

Polycarbonates

Tough, transparent, stiff and strong. Good electrical insulation properties. Polycarbonates have moderate outdoor weather resistance. Dissolved by chlorinated paraffins, cresol,dioxane. Attacked by hydrocarbons.

Polycarbonates can be injection moulded, extruded, blow moulded, and vacuum formed.

Typical applications include street lamp covers, safety helmets.

Polysulphones

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.

Polyacetals..

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.

Thermoplastic Polyester.

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..Polytetrafluoroethylene.

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.