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Phenol formaldehyde plastics
Characteristics.
Moulded Plastics.
Colour: Resin itself tends to be amber-coloured.
General Physical Properties:
Wide variation depending on fillers and nature of resin.
Smooth, lustrous surface.
Usually hard and rigid, with good dimensional stability.
May be brittle in thin sections with low impact strength.
Easy to mould.
Heavier than water (S.G. 1.30-1.45)
Water: Water may be absorbed causing some loss of insulation properties.
Heat: Thermosetting. Do not soften on heating, but decompose at high
temperatures.
Retain properties at freezing temperatures.
Good dimensional stability on heating up to about 300 deg. F.
Poor conductors of heat, so that handles of pans etc stay cool to touch.
Burn only with difficulty.
Solvents and chemicals:
Good resistance to alcohol, oils, greases and most common solvents and
to weak acid and alkali.
Light: Tend to darken on prolonged exposure.
Age: Negligible deterioration.
Electrical: Good electrical insulators.
Laminated Plastics.
Properties generally related to those of moulded plastics.
Improved strength and dimensional stability.
Improved impact resistance.
Cast Resins.
Colour: Good. Transparent and may be colourless.
General Physical Properties:
Hard and rigid.
Good dimensional stability under normal conditions.
Tend to be brittle, with low impact strength.
Easily machined and polished.
Other Properties:
Generally similar to those of moulded plastics.
Applications
Moulding Materials.
A wide range of moulding powders is available in which the composition
of the resin, fillers etc is varied to provide mouldings suitable for
many purposes. Compression and transfer processes commonly used.
Examples of Uses: Electrical equipment; caps; handles; buttons; radio
cabinets; furniture; knobs; vacuum cleaners; cameras; ash trays; engine
ignition equipment.
Laminated Material.
Laminated sheets, rods and tubes are made in great variety from fabric,
paper, wood veneers etc impregnated with phenolic, resins providing a
range of materials of widely differing properties.
Examples of Uses: Electrical equipment; building panels gears and
bearings; chemical equipment; air plane parts; clutch and brake linings;
jigs and dies.
Cast Resins.
Phenolic resins of several types are produced for casting and potting.
Examples of Uses: Imitation jewelery; ornaments; handles and knobs;
advertising displays; instrument panels; jigs and dies.
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