Polypropylene

Acronym and details:   PP

Group:   thermoplastic

Developed:   from 1954; increase in use from 1976 when initial patents ran out; became fashionable in translucent sheet form in 1990s; now one of the most used plastics

Trade names:   Propathene

Manufacturing process:   blow moulding; extrusion (as a fibre); injection moulding

Cost:   low

Colour:   any

Transparency:   translucent, but can have clarifying agents added making it transparent; also comes as clear film (modern cellophane)

Rigidity:   rigid but flexible

Feel:   varies

Smell:   none

Other:   can be moulded to create an integral hinge; can achieve reasonably glossy surface scratches with fingernail

Typical uses:   chair shells and garden furniture; luggage; car bumper; petrol cans; food wrappings; microwaveable meal trays; margarine tubs; netting; household goods; carpets; packaging; rope

Degradation:   relatively stable