1.2-Performance characteristics of polymers Flashcards
Granules (stock form)
a small particle of plastic
Sheet (stock form)
Large, flat sections of polymer in varying thickness
Film (stock form)
Very thin sheet polymer
Rods and other extruded forms, tubes, bars
- Rods and extruded forms can be a specific designed shape
- Bar- sold form, square or round
- Tube- hollow cross section, square, rectangular or round
Foam (stock form)
Solid form made by including air or other gases, such as styrofoam from expanded polystyrene
Powder (stock form)
Very fine granule of powder
Characteristics of polymers
- majority of polymers made via fractional distillation of crude oil (non renewable resource)
- synthetic polymers made from crude oil and take ages to degrade
- polymers are ‘self finishing’ (can be pigmented during manufacture process for colour)
- can be split into three types- thermoplastics, thermoset polymer and elastomer
What are thermoplastics
material that can be reheated and reshaped repeatedly, allowing it to be recycled after its initial use
What is a thermoset polymer
a material that, when heated, undergoes a chemical change where the molecules form rigid cross links
-cannot be reheated and reshaped
What is an elastomer
a material that, at room temperature, can be deformed under pressure
-upon release of pressure, it will return to its original shape
Thermoplastics- Low density polyethelence (LDPE)- properties and characteristics
- tough, good chemical resistance, weather proof, available in translucent
- squeezy detergent bottles, toys, bin liners, food trays
Thermoplastics- High density polyethelence (HDPE)- properties and characteristics
- available in translucent form, weather proof, tough, good chemical resistance
- chemical drums, jerry cans, toys, bowls
Thermoplastics- Polypropylene (PP)- properties and characteristics
- available in translucent, good chemical resistance, tough, good hinge property
- rope, folders, folio cases
Thermoplastics- High impact polystyrene (HIPS)- properties and characteristics
- hard, rigid, available in translucent, tough
- yoghurt pots, refrigerator linings, single use drinks cups
Thermoplastics- Acrylonitrile butadiene (ABS)- properties and characteristics
- tough, hard, available in opaque
- telephone handsets, rigid luggae, domestic appliances, calculator cases